From patchwork Mon Jun 26 14:16:50 2023 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Christian Brauner X-Patchwork-Id: 13293022 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 4D6C7EB64DA for ; Mon, 26 Jun 2023 14:19:42 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S231629AbjFZOTk (ORCPT ); Mon, 26 Jun 2023 10:19:40 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:35438 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S229472AbjFZOTC (ORCPT ); Mon, 26 Jun 2023 10:19:02 -0400 Received: from dfw.source.kernel.org (dfw.source.kernel.org [IPv6:2604:1380:4641:c500::1]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 70D662977; Mon, 26 Jun 2023 07:18:33 -0700 (PDT) Received: from smtp.kernel.org (relay.kernel.org [52.25.139.140]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature RSA-PSS (2048 bits)) (No client certificate requested) by dfw.source.kernel.org (Postfix) with ESMTPS id 6889460EA5; Mon, 26 Jun 2023 14:17:13 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id 5A1D0C433CB; Mon, 26 Jun 2023 14:17:11 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1687789032; bh=3iOllktOx2ArKFRO/7jbpoYrOUrV2Y7iRVVV7NXtwKg=; h=From:Date:Subject:References:In-Reply-To:To:Cc:From; b=ZBR553rlFgEjJzJQaHht87wVTaEKGkScS+DUZj72TJdJp3eMnxAaWzCB4oX7kOP9K 9piJWLW+QuZ4OF5yeUugxnxqjX+vjexur2cUW8+11AT8FvvwyuOQ9+jaT+YYNnT+ZL 6kcm308Dhu0IK7ejptMnCBE0NIkt+XO+mG2Kc6URGgNc0W65tUCKYd+2iM5XyH8D4F TLSmqs2lM7eJUWxPlHUFWXLoIELyFK9ZfrSukruZWrGe7zbj6/AoQtws9Zj00xPeXo wdM2q+SzQv+fltK4PidnbqnzXQzpI5ZMMZNS8+s5HuwrVre/jJOaUOfw4kqBAg3lh0 fyBoQSZA3DU9w== From: Christian Brauner Date: Mon, 26 Jun 2023 16:16:50 +0200 Subject: [PATCH 1/2] fs: indicate request originates from old mount api MIME-Version: 1.0 Message-Id: <20230626-fs-btrfs-mount-api-v1-1-045e9735a00b@kernel.org> References: <20230626-fs-btrfs-mount-api-v1-0-045e9735a00b@kernel.org> In-Reply-To: <20230626-fs-btrfs-mount-api-v1-0-045e9735a00b@kernel.org> To: Chris Mason , Josef Bacik , David Sterba , Nick Terrell Cc: linux-btrfs@vger.kernel.org, linux-fsdevel@vger.kernel.org, Christian Brauner X-Mailer: b4 0.13-dev-099c9 X-Developer-Signature: v=1; a=openpgp-sha256; l=1343; i=brauner@kernel.org; h=from:subject:message-id; bh=3iOllktOx2ArKFRO/7jbpoYrOUrV2Y7iRVVV7NXtwKg=; b=owGbwMvMwCU28Zj0gdSKO4sYT6slMaTMnPvkdP81xXcFAf+nf+SzP27Cudwj97Cj/4rNnbcWH81+ vG6JbEcpC4MYF4OsmCKLQ7tJuNxynorNRpkaMHNYmUCGMHBxCsBETGUZGb4xSVn971t9ak7IsVcyxf cOyDmpNk8Qj//aGmqsEuuhfpjhv0/JQttPr5aejru69muxwETnConTsvO1XCu5BKNn5bRrsgIA X-Developer-Key: i=brauner@kernel.org; a=openpgp; fpr=4880B8C9BD0E5106FC070F4F7B3C391EFEA93624 Precedence: bulk List-ID: X-Mailing-List: linux-btrfs@vger.kernel.org We already communicate to filesystems when a remount request comes from the old mount api as some filesystems choose to implement different behavior in the new mount api than the old mount api to e.g., take the chance to fix significant api bugs. Allow the same for regular mount requests. Signed-off-by: Christian Brauner --- fs/namespace.c | 11 +++++++++++ 1 file changed, 11 insertions(+) diff --git a/fs/namespace.c b/fs/namespace.c index 54847db5b819..7a74f8f703ca 100644 --- a/fs/namespace.c +++ b/fs/namespace.c @@ -2692,7 +2692,12 @@ static int do_remount(struct path *path, int ms_flags, int sb_flags, if (IS_ERR(fc)) return PTR_ERR(fc); + /* + * Indicate to the filesystem that the remount request is coming + * from the legacy mount system call. + */ fc->oldapi = true; + err = parse_monolithic_mount_data(fc, data); if (!err) { down_write(&sb->s_umount); @@ -3026,6 +3031,12 @@ static int do_new_mount(struct path *path, const char *fstype, int sb_flags, if (IS_ERR(fc)) return PTR_ERR(fc); + /* + * Indicate to the filesystem that the mount request is coming + * from the legacy mount system call. + */ + fc->oldapi = true; + if (subtype) err = vfs_parse_fs_string(fc, "subtype", subtype, strlen(subtype)); From patchwork Mon Jun 26 14:16:51 2023 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Christian Brauner X-Patchwork-Id: 13293023 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 32A19EB64D7 for ; Mon, 26 Jun 2023 14:20:15 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S231931AbjFZOUM (ORCPT ); Mon, 26 Jun 2023 10:20:12 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:35178 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S231408AbjFZOTP (ORCPT ); Mon, 26 Jun 2023 10:19:15 -0400 Received: from dfw.source.kernel.org (dfw.source.kernel.org [IPv6:2604:1380:4641:c500::1]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 6179710E4; Mon, 26 Jun 2023 07:18:39 -0700 (PDT) Received: from smtp.kernel.org (relay.kernel.org [52.25.139.140]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature RSA-PSS (2048 bits)) (No client certificate requested) by dfw.source.kernel.org (Postfix) with ESMTPS id D481560E8C; Mon, 26 Jun 2023 14:17:15 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id 536D3C433C9; Mon, 26 Jun 2023 14:17:13 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1687789035; bh=ox51D2RLll22NeAm3Fc2Ql02olAEhMIZTohhLguFykg=; h=From:Date:Subject:References:In-Reply-To:To:Cc:From; b=lzpLkqEyPg8bF14zDDxft55I+3HF41dGrOdore1GQwlUadDOnHvCby6AFNTe37ud1 Uk/FiE86WIBS7BtmRtoJL0oXwuno5PiVNOQZMFdPzR0WB0JLuRDRhd+T4lop52NVGa BaBRu3d4ahpQKD0yPqjXbLNxGlP7RdvM2A67n/4ha7gFgDKvISH7rqcVTGczGbjl52 w1RNAJeoCWno3Dx+9NXz1Ki0ZRYic04Sc3gdUC689E4jX9LQ6JiSSxVGgHt5ix/Fsc FbvBj2fK2CAga7KO5foV2TE5CPu2JIaeWpYXGxIXaWmjDwrxYCtW3O6KuXCWDCCD60 d5+Mk3cz/aV+w== From: Christian Brauner Date: Mon, 26 Jun 2023 16:16:51 +0200 Subject: [PATCH 2/2] btrfs: port to new mount api MIME-Version: 1.0 Message-Id: <20230626-fs-btrfs-mount-api-v1-2-045e9735a00b@kernel.org> References: <20230626-fs-btrfs-mount-api-v1-0-045e9735a00b@kernel.org> In-Reply-To: <20230626-fs-btrfs-mount-api-v1-0-045e9735a00b@kernel.org> To: Chris Mason , Josef Bacik , David Sterba , Nick Terrell Cc: linux-btrfs@vger.kernel.org, linux-fsdevel@vger.kernel.org, Christian Brauner X-Mailer: b4 0.13-dev-099c9 X-Developer-Signature: v=1; a=openpgp-sha256; l=108796; i=brauner@kernel.org; h=from:subject:message-id; bh=ox51D2RLll22NeAm3Fc2Ql02olAEhMIZTohhLguFykg=; b=owGbwMvMwCU28Zj0gdSKO4sYT6slMaTMnPs0cq36tV+v7/XsrDk5dVPWh1JOv+UqyrncyQvZO+sP /1bb3VHKwiDGxSArpsji0G4SLrecp2KzUaYGzBxWJpAhDFycAjCRI3MZ/sfueW29er5W6qMN30LVC1 nYbz3ljTs12/rBt3vs22W1u0wY/tnGaiXGbDrHKB/NlbrzTkxPylmfiPsLV4ooK8WtOHrNjAEA X-Developer-Key: i=brauner@kernel.org; a=openpgp; fpr=4880B8C9BD0E5106FC070F4F7B3C391EFEA93624 Precedence: bulk List-ID: X-Mailing-List: linux-btrfs@vger.kernel.org Signed-off-by: Christian Brauner --- fs/btrfs/Makefile | 2 +- fs/btrfs/disk-io.c | 9 +- fs/btrfs/disk-io.h | 5 +- fs/btrfs/params.c | 1770 ++++++++++++++++++++++++++++++++++++++++++++++++++++ fs/btrfs/params.h | 21 + fs/btrfs/super.c | 1500 +------------------------------------------- fs/btrfs/super.h | 7 +- 7 files changed, 1815 insertions(+), 1499 deletions(-) diff --git a/fs/btrfs/Makefile b/fs/btrfs/Makefile index 90d53209755b..62886b39fa7f 100644 --- a/fs/btrfs/Makefile +++ b/fs/btrfs/Makefile @@ -33,7 +33,7 @@ btrfs-y += super.o ctree.o extent-tree.o print-tree.o root-tree.o dir-item.o \ uuid-tree.o props.o free-space-tree.o tree-checker.o space-info.o \ block-rsv.o delalloc-space.o block-group.o discard.o reflink.o \ subpage.o tree-mod-log.o extent-io-tree.o fs.o messages.o bio.o \ - lru_cache.o + lru_cache.o params.o btrfs-$(CONFIG_BTRFS_FS_POSIX_ACL) += acl.o btrfs-$(CONFIG_BTRFS_FS_CHECK_INTEGRITY) += check-integrity.o diff --git a/fs/btrfs/disk-io.c b/fs/btrfs/disk-io.c index fbf9006c6234..20b0df76703d 100644 --- a/fs/btrfs/disk-io.c +++ b/fs/btrfs/disk-io.c @@ -52,6 +52,7 @@ #include "relocation.h" #include "scrub.h" #include "super.h" +#include "params.h" #define BTRFS_SUPER_FLAG_SUPP (BTRFS_HEADER_FLAG_WRITTEN |\ BTRFS_HEADER_FLAG_RELOC |\ @@ -3339,8 +3340,8 @@ int btrfs_check_features(struct btrfs_fs_info *fs_info, bool is_rw_mount) return 0; } -int __cold open_ctree(struct super_block *sb, struct btrfs_fs_devices *fs_devices, - char *options) +int __cold open_ctree(struct fs_context *fc, struct super_block *sb, + struct btrfs_fs_devices *fs_devices) { u32 sectorsize; u32 nodesize; @@ -3477,8 +3478,8 @@ int __cold open_ctree(struct super_block *sb, struct btrfs_fs_devices *fs_device fs_info->csums_per_leaf = BTRFS_MAX_ITEM_SIZE(fs_info) / fs_info->csum_size; fs_info->stripesize = stripesize; - ret = btrfs_parse_options(fs_info, options, sb->s_flags); - if (ret) + ret = btrfs_fs_params_verify(fs_info, fc); + if (ret < 0) goto fail_alloc; ret = btrfs_check_features(fs_info, !sb_rdonly(sb)); diff --git a/fs/btrfs/disk-io.h b/fs/btrfs/disk-io.h index 4d5772330110..35d0cb97a1a9 100644 --- a/fs/btrfs/disk-io.h +++ b/fs/btrfs/disk-io.h @@ -45,9 +45,8 @@ void btrfs_clear_oneshot_options(struct btrfs_fs_info *fs_info); int btrfs_start_pre_rw_mount(struct btrfs_fs_info *fs_info); int btrfs_check_super_csum(struct btrfs_fs_info *fs_info, const struct btrfs_super_block *disk_sb); -int __cold open_ctree(struct super_block *sb, - struct btrfs_fs_devices *fs_devices, - char *options); +int __cold open_ctree(struct fs_context *fc, struct super_block *sb, + struct btrfs_fs_devices *fs_devices); void __cold close_ctree(struct btrfs_fs_info *fs_info); int btrfs_validate_super(struct btrfs_fs_info *fs_info, struct btrfs_super_block *sb, int mirror_num); diff --git a/fs/btrfs/params.c b/fs/btrfs/params.c new file mode 100644 index 000000000000..0e90caef2ca4 --- /dev/null +++ b/fs/btrfs/params.c @@ -0,0 +1,1770 @@ +// SPDX-License-Identifier: GPL-2.0 +/* + * Copyright (C) 2023 Christian Brauner. + */ + +#include "ctree.h" +#include "defrag.h" +#include "dev-replace.h" +#include "dir-item.h" +#include "discard.h" +#include "disk-io.h" +#include "messages.h" +#include "qgroup.h" +#include "scrub.h" +#include "super.h" +#include "zoned.h" +#include "accessors.h" +#include "params.h" + +enum btrfs_get_tree_t { + BTRFS_FS_CONTEXT_PREPARE, + BTRFS_FS_CONTEXT_SUPER, + BTRFS_FS_CONTEXT_SUBTREE, +}; + +enum space_cache_t { + BTRFS_FS_CONTEXT_SPACE_CACHE_DEFAULT = 0, + BTRFS_FS_CONTEXT_SPACE_CACHE_V1 = 1, + BTRFS_FS_CONTEXT_SPACE_CACHE_V2 = 2, + BTRFS_FS_CONTEXT_SPACE_CACHE_OFF = 3, +}; + +/* Let the btrfs_fs_context hold all mount options. */ +struct btrfs_fs_context { + refcount_t refs; + enum btrfs_get_tree_t phase; + + /* subvolume mount options */ + char *subvol_name; + u64 subvol_id; + struct vfsmount *root_mnt; + + /* generic mount options */ + unsigned long mount_opt; + + u8 has_space_cache:1; + u8 has_compression:1; + u8 has_commit_interval:1; + u8 has_max_inline:1; + u8 has_metadata_ratio:1; + u8 has_clear_cache:1; +#ifdef CONFIG_BTRFS_FS_CHECK_INTEGRITY + u8 has_check_integrity_print_mask:1; + u32 check_integrity_print_mask; +#endif + + enum space_cache_t space_cache; + unsigned long compress_type:4; + unsigned int compress_level; + u32 commit_interval; + u64 max_inline; + u32 metadata_ratio; + u32 thread_pool_size; + + /* device mount options */ + size_t capacity; + size_t nr; + char **device_paths; +}; + +enum { + Opt_acl, + Opt_clear_cache, + Opt_commit_interval, + Opt_compress, + Opt_compress_force, + Opt_degraded, + Opt_device, + Opt_fatal_errors, + Opt_flushoncommit, + Opt_max_inline, + Opt_barrier, + Opt_datacow, + Opt_datasum, + Opt_defrag, + Opt_discard, + Opt_nodiscard, + Opt_norecovery, + Opt_ratio, + Opt_rescan_uuid_tree, + Opt_skip_balance, + Opt_space_cache, + Opt_no_space_cache, + Opt_ssd, + Opt_ssd_spread, + Opt_subvol, + Opt_subvolid, + Opt_thread_pool, + Opt_treelog, + Opt_user_subvol_rm_allowed, + + /* Rescue options */ + Opt_rescue, + Opt_usebackuproot, + Opt_nologreplay, + + /* Deprecated options */ + Opt_recovery, + Opt_inode_cache, + + /* Debugging options */ + Opt_check_integrity, + Opt_check_integrity_including_extent_data, + Opt_check_integrity_print_mask, + Opt_enospc_debug, +#ifdef CONFIG_BTRFS_DEBUG + Opt_fragment, +#endif +#ifdef CONFIG_BTRFS_FS_REF_VERIFY + Opt_ref_verify, +#endif +}; + +enum { + BTRFS_PARAM_RESCUE_USEBACKUPROOT, + BTRFS_PARAM_RESCUE_NOLOGREPLAY, + BTRFS_PARAM_RESCUE_IGNOREBADROOTS, + BTRFS_PARAM_RESCUE_IGNOREDATACSUMS, + BTRFS_PARAM_RESCUE_RESCUE_ALL, +}; + +static const struct constant_table btrfs_rescue_parameters[] = { + { "usebackuproot", BTRFS_PARAM_RESCUE_USEBACKUPROOT }, + { "nologreplay", BTRFS_PARAM_RESCUE_NOLOGREPLAY }, + { "ignorebadroots", BTRFS_PARAM_RESCUE_IGNOREBADROOTS }, + { "ibadroots", BTRFS_PARAM_RESCUE_IGNOREBADROOTS }, + { "ignoredatacsums", BTRFS_PARAM_RESCUE_IGNOREDATACSUMS }, + { "all", BTRFS_PARAM_RESCUE_RESCUE_ALL }, + {} +}; + +#ifdef CONFIG_BTRFS_DEBUG +enum { + BTRFS_PARAM_FRAGMENT_DATA, + BTRFS_PARAM_FRAGMENT_METADATA, + BTRFS_PARAM_FRAGMENT_ALL, +}; + +static const struct constant_table btrfs_fragment_parameters[] = { + { "data", BTRFS_PARAM_FRAGMENT_DATA }, + { "metadata", BTRFS_PARAM_FRAGMENT_METADATA }, + { "all", BTRFS_PARAM_FRAGMENT_ALL }, + {} +}; +#endif + +#define fsparam_string_empty(NAME, OPT) \ + __fsparam(fs_param_is_string, NAME, OPT, fs_param_can_be_empty, NULL) + +const struct fs_parameter_spec btrfs_parameter_spec[] = { + fsparam_flag_no ("acl", Opt_acl), + fsparam_flag ("clear_cache", Opt_clear_cache), + fsparam_u32 ("commit", Opt_commit_interval), + fsparam_flag ("compress", Opt_compress), + fsparam_string ("compress", Opt_compress), + fsparam_flag ("compress-force", Opt_compress_force), + fsparam_string ("compress-force", Opt_compress_force), + fsparam_flag ("degraded", Opt_degraded), + fsparam_string_empty ("device", Opt_device), + fsparam_string ("fatal_errors", Opt_fatal_errors), + fsparam_flag_no ("flushoncommit", Opt_flushoncommit), + fsparam_flag_no ("inode_cache", Opt_inode_cache), + fsparam_string ("max_inline", Opt_max_inline), + fsparam_flag_no ("barrier", Opt_barrier), + fsparam_flag_no ("datacow", Opt_datacow), + fsparam_flag_no ("datasum", Opt_datasum), + fsparam_flag_no ("autodefrag", Opt_defrag), + fsparam_flag ("discard", Opt_discard), + fsparam_string ("discard", Opt_discard), + fsparam_flag ("nodiscard", Opt_nodiscard), + + /* norecovery is deprecated */ + fsparam_flag ("recovery", Opt_recovery), + fsparam_flag ("norecovery", Opt_norecovery), + fsparam_u32 ("metadata_ratio", Opt_ratio), + fsparam_flag ("rescan_uuid_tree", Opt_rescan_uuid_tree), + fsparam_flag ("skip_balance", Opt_skip_balance), + fsparam_flag ("space_cache", Opt_space_cache), + fsparam_string ("space_cache", Opt_space_cache), + fsparam_flag ("nospace_cache", Opt_no_space_cache), + fsparam_flag_no ("ssd", Opt_ssd), + fsparam_flag_no ("ssd_spread", Opt_ssd_spread), + fsparam_flag ("subvol", Opt_subvol), + fsparam_string_empty ("subvol", Opt_subvol), + fsparam_u64 ("subvolid", Opt_subvolid), + fsparam_u32 ("thread_pool", Opt_thread_pool), + fsparam_flag_no ("treelog", Opt_treelog), + fsparam_flag ("user_subvol_rm_allowed", Opt_user_subvol_rm_allowed), + + /* Rescue options */ + fsparam_enum ("rescue", Opt_rescue, btrfs_rescue_parameters), + + /* Deprecated, with alias rescue=nologreplay */ + fsparam_flag ("nologreplay", Opt_nologreplay), + + /* Deprecated, with alias rescue=usebackuproot */ + fsparam_flag ("usebackuproot", Opt_usebackuproot), + + /* Debugging options */ + fsparam_flag ("check_int", Opt_check_integrity), + fsparam_flag ("check_int_data", Opt_check_integrity_including_extent_data), + fsparam_u32 ("check_int_print_mask", Opt_check_integrity_print_mask), + fsparam_flag_no ("enospc_debug", Opt_enospc_debug), + +#ifdef CONFIG_BTRFS_DEBUG + fsparam_enum ("fragment", Opt_fragment, btrfs_fragment_parameters), +#endif +#ifdef CONFIG_BTRFS_FS_REF_VERIFY + fsparam_flag ("ref_verify", Opt_ref_verify), +#endif + + {} +}; + +#define btrfs_param_info(fc, fmt, args...) \ + do { \ + static_assert(__same_type(typeof(fc), struct fs_context *)); \ + btrfs_info(fc->s_fs_info, fmt, ##args); \ + } while (0) + +#define btrfs_param_warn(fc, fmt, args...) \ + do { \ + static_assert(__same_type(typeof(fc), struct fs_context *)); \ + btrfs_warn(fc->s_fs_info, fmt, ##args); \ + } while (0) + +#define btrfs_param_err(fc, fmt, args...) \ + do { \ + static_assert(__same_type(typeof(fc), struct fs_context *)); \ + btrfs_err(fc->s_fs_info, fmt, ##args); \ + } while (0) + +#define btrfs_param_clear_info(fc, ctx, opt, fmt, args...) \ + do { \ + static_assert( \ + __same_type(typeof(ctx), struct btrfs_fs_context *)); \ + if (btrfs_test_opt(ctx, opt)) \ + btrfs_param_info(fc, fmt, ##args); \ + btrfs_clear_opt(ctx->mount_opt, opt); \ + } while (0) + +#define btrfs_param_set_info(fc, ctx, opt, fmt, args...) \ + do { \ + static_assert( \ + __same_type(typeof(ctx), struct btrfs_fs_context *)); \ + if (!btrfs_test_opt(ctx, opt)) \ + btrfs_param_info(fc, fmt, ##args); \ + btrfs_set_opt(ctx->mount_opt, opt); \ + } while (0) + +static void btrfs_fs_context_to_info(struct btrfs_fs_context *ctx, + struct btrfs_fs_info *fs_info) +{ + fs_info->mount_opt = ctx->mount_opt; + + if (ctx->has_metadata_ratio) + fs_info->metadata_ratio = ctx->metadata_ratio; + + if (ctx->has_compression) { + fs_info->compress_type = ctx->compress_type; + fs_info->compress_level = ctx->compress_level; + } + + if (ctx->has_commit_interval) + fs_info->commit_interval = ctx->commit_interval; + + if (ctx->has_max_inline) + fs_info->max_inline = + min_t(u64, ctx->max_inline, fs_info->sectorsize); + + if (ctx->thread_pool_size) + fs_info->thread_pool_size = ctx->thread_pool_size; + +#ifdef CONFIG_BTRFS_FS_CHECK_INTEGRITY + if (ctx->has_check_integrity_print_mask) + fs_info->check_integrity_print_mask = + ctx->check_integrity_print_mask; +#endif +} + +static void btrfs_fs_info_to_context(struct btrfs_fs_context *ctx, + struct btrfs_fs_info *fs_info) +{ + ctx->mount_opt = fs_info->mount_opt; + ctx->compress_type = fs_info->compress_type; + ctx->compress_level = fs_info->compress_level; + ctx->thread_pool_size = fs_info->thread_pool_size; + ctx->commit_interval = fs_info->commit_interval; + ctx->metadata_ratio = fs_info->metadata_ratio; + ctx->max_inline = fs_info->max_inline; +#ifdef CONFIG_BTRFS_FS_CHECK_INTEGRITY + ctx->check_integrity_print_mask = fs_info->check_integrity_print_mask; +#endif +} + +static bool check_ro_option(struct fs_context *fc, struct btrfs_fs_context *ctx, + unsigned long opt, const char *opt_name) +{ + if (!(ctx->mount_opt & opt)) + return false; + + btrfs_param_err(fc, "%s must be used with ro mount option", opt_name); + return true; +} + +int btrfs_fs_params_verify(struct btrfs_fs_info *info, struct fs_context *fc) +{ + struct btrfs_fs_context *ctx = fc->fs_private; + bool is_remount = (fc->purpose == FS_CONTEXT_FOR_RECONFIGURE); + int ret = 0; + + /* + * At this point we've read the superblock from disk and we need + * to take the default space cache options into account. + */ + if (btrfs_fs_compat_ro(info, FREE_SPACE_TREE)) + btrfs_set_opt(ctx->mount_opt, FREE_SPACE_TREE); + else if (btrfs_free_space_cache_v1_active(info)) { + if (btrfs_is_zoned(info)) { + btrfs_param_info(fc, "zoned: clearing existing space cache"); + btrfs_set_super_cache_generation(info->super_copy, 0); + } else { + btrfs_set_opt(ctx->mount_opt, SPACE_CACHE); + } + } + + /* + * To set space cache options we need to have the on-disk + * superblock information around. During mount this needs to + * happen after the on-disk superblock has been read from disk. + * For reconfiguration this has already happened. + */ + if (ctx->has_space_cache) { + switch (ctx->space_cache) { + case BTRFS_FS_CONTEXT_SPACE_CACHE_DEFAULT: + break; + case BTRFS_FS_CONTEXT_SPACE_CACHE_V1: + /* + * We already set FREE_SPACE_TREE above because + * we have compat_ro(FREE_SPACE_TREE) set, and + * we aren't going to allow v1 to be set for + * extent tree v2, simply ignore this setting if + * we're extent tree v2. + */ + if (btrfs_fs_incompat(info, EXTENT_TREE_V2)) + break; + + btrfs_clear_opt(ctx->mount_opt, FREE_SPACE_TREE); + if (is_remount && !btrfs_test_opt(info, SPACE_CACHE)) + btrfs_param_info(fc, + "enabling disk space caching"); + btrfs_set_opt(ctx->mount_opt, SPACE_CACHE); + break; + case BTRFS_FS_CONTEXT_SPACE_CACHE_V2: + /* + * We already set FREE_SPACE_TREE above because + * we have compat_ro(FREE_SPACE_TREE) set, and + * we aren't going to allow v1 to be set for + * extent tree v2, simply ignore this setting if + * we're extent tree v2. + */ + if (btrfs_fs_incompat(info, EXTENT_TREE_V2)) + break; + + btrfs_clear_opt(ctx->mount_opt, SPACE_CACHE); + if (is_remount && + !btrfs_test_opt(info, FREE_SPACE_TREE)) + btrfs_param_info(fc, "enabling free space tree"); + btrfs_set_opt(ctx->mount_opt, FREE_SPACE_TREE); + break; + case BTRFS_FS_CONTEXT_SPACE_CACHE_OFF: + /* + * We cannot operate without the free space tree + * with extent tree v2, ignore this option. + */ + if (btrfs_fs_incompat(info, EXTENT_TREE_V2)) + break; + + if (is_remount && btrfs_test_opt(info, SPACE_CACHE)) + btrfs_param_info( + fc, "disabling disk space caching"); + btrfs_clear_opt(ctx->mount_opt, SPACE_CACHE); + + if (is_remount && btrfs_test_opt(info, FREE_SPACE_TREE)) + btrfs_param_info(fc, + "disabling free space tree"); + btrfs_clear_opt(ctx->mount_opt, FREE_SPACE_TREE); + break; + default: + /* not reached */ + WARN_ON(true); + ret = -EINVAL; + } + } + + /* + * We cannot clear the free space tree with extent tree v2, + * ignore this option. + */ + if (!btrfs_fs_incompat(info, EXTENT_TREE_V2) && ctx->has_clear_cache) { + if (is_remount && btrfs_test_opt(info, CLEAR_CACHE)) + btrfs_param_info(fc, "force clearing of disk cache"); + btrfs_set_opt(ctx->mount_opt, CLEAR_CACHE); + } + + if (!(fc->sb_flags & SB_RDONLY)) { + if (check_ro_option(fc, ctx, BTRFS_MOUNT_NOLOGREPLAY, + "nologreplay") || + check_ro_option(fc, ctx, BTRFS_MOUNT_IGNOREBADROOTS, + "ignorebadroots") || + check_ro_option(fc, ctx, BTRFS_MOUNT_IGNOREDATACSUMS, + "ignoredatacsums")) + ret = -EINVAL; + } + + if (ctx->has_compression) { + switch (ctx->compress_type) { + case BTRFS_COMPRESS_LZO: + btrfs_set_fs_incompat(info, COMPRESS_LZO); + break; + case BTRFS_COMPRESS_ZSTD: + btrfs_set_fs_incompat(info, COMPRESS_ZSTD); + break; + } + } + + if (btrfs_fs_compat_ro(info, FREE_SPACE_TREE) && + !btrfs_test_opt(ctx, FREE_SPACE_TREE) && + !btrfs_test_opt(ctx, CLEAR_CACHE)) { + btrfs_param_err(fc, "cannot disable free space tree"); + ret = -EINVAL; + } + if (btrfs_fs_compat_ro(info, BLOCK_GROUP_TREE) && + !btrfs_test_opt(ctx, FREE_SPACE_TREE)) { + btrfs_param_err(fc, + "cannot disable free space tree with block-group-tree feature"); + ret = -EINVAL; + } + if (!ret) + ret = btrfs_check_mountopts_zoned(info); + if (!ret && !is_remount) { + if (btrfs_test_opt(ctx, SPACE_CACHE)) + btrfs_param_info(fc, "disk space caching is enabled"); + if (btrfs_test_opt(ctx, FREE_SPACE_TREE)) + btrfs_param_info(fc, "using free space tree"); + } + + /* + * Copy mount options over into superblock. On failure the old + * values will be restored. Technically, this can and should at + * some point be rewritten to only rely on @btrfs_fs_context and + * to defer committing the new values after all validation has + * been done. This would work but would mean a lot more work. + */ + btrfs_fs_context_to_info(ctx, info); + return ret; +} + +static void btrfs_parse_param_drop_devices(struct btrfs_fs_context *ctx) +{ + for (size_t nr = 0; nr < ctx->nr; nr++) { + kfree(ctx->device_paths[nr]); + ctx->device_paths[nr] = NULL; + } + ctx->nr = 0; +} + +/* + * Currently we parse the device names. What we should really do in the + * future is to resolve these device names to paths and stash paths + * here. And then resolve those paths to block devices during + * ->get_tree(). + */ +static int btrfs_parse_param_device(struct fs_parameter *param, + struct fs_context *fc) +{ + struct btrfs_fs_context *ctx = fc->fs_private; + char **pp; + + if (!*param->string) { + btrfs_parse_param_drop_devices(ctx); + return 0; + } + + if (ctx->nr + 1 >= ctx->capacity) { + pp = krealloc_array(ctx->device_paths, ctx->nr + 1, + sizeof(*ctx->device_paths), + GFP_KERNEL_ACCOUNT); + if (!pp) + return -ENOMEM; + + ctx->device_paths = pp; + ctx->capacity = ctx->nr + 1; + } + + /* + * It's legitimate to steal the parameter's value. We just need + * to make sure to NULL it. + */ + ctx->device_paths[ctx->nr] = param->string; + param->string = NULL; + ctx->nr++; + return 0; +} + +static inline bool btrfs_param_is_flag(const struct fs_parameter *param) +{ + return param->type == fs_value_is_flag; +} + +static int btrfs_parse_param(struct fs_context *fc, struct fs_parameter *param) +{ + struct btrfs_fs_context *ctx = fc->fs_private; + bool is_remount = (fc->purpose == FS_CONTEXT_FOR_RECONFIGURE); + struct fs_parse_result result; + char *compress_type; + bool compress_force = false, saved_compress_type, saved_compress_force, + saved_compress_level; + int no_compress = 0; + char *dup = NULL; + int ret = 0; + int opt; + + opt = fs_parse(fc, btrfs_parameter_spec, param, &result); + if (opt < 0) + return opt; + + switch (opt) { + case Opt_degraded: + btrfs_param_info(fc, "allowing degraded mounts"); + btrfs_set_opt(ctx->mount_opt, DEGRADED); + break; + case Opt_subvol: + if (is_remount && !fc->oldapi) + return -EINVAL; + + /* "subvol", just ignore */ + if (btrfs_param_is_flag(param)) + break; + + if (*param->string) { + dup = kstrdup(param->string, GFP_KERNEL); + if (!dup) { + ret = -ENOMEM; + break; + } + } + kfree(ctx->subvol_name); + ctx->subvol_name = dup; + break; + case Opt_subvolid: + if (is_remount && !fc->oldapi) + return -EINVAL; + + if (result.uint_64 == 0) + ctx->subvol_id = BTRFS_FS_TREE_OBJECTID; + else + ctx->subvol_id = result.uint_64; + break; + case Opt_device: + if (is_remount && !fc->oldapi) + ret = -EINVAL; + else + ret = btrfs_parse_param_device(param, fc); + break; + case Opt_datasum: + if (!result.negated) { + if (btrfs_test_opt(ctx, NODATASUM)) { + if (btrfs_test_opt(ctx, NODATACOW)) + btrfs_param_info(fc, "setting datasum, datacow enabled"); + else + btrfs_param_info(fc, "setting datasum"); + } + btrfs_clear_opt(ctx->mount_opt, NODATACOW); + btrfs_clear_opt(ctx->mount_opt, NODATASUM); + } else { + btrfs_param_set_info(fc, ctx, NODATASUM, "setting nodatasum"); + } + break; + case Opt_datacow: + if (!result.negated) { + btrfs_param_clear_info(fc, ctx, NODATACOW, "setting datacow"); + } else { + if (!btrfs_test_opt(ctx, NODATACOW)) { + if (!btrfs_test_opt(ctx, COMPRESS) || + !btrfs_test_opt(ctx, FORCE_COMPRESS)) { + btrfs_param_info(fc, "setting nodatacow, compression disabled"); + } else { + btrfs_param_info(fc, "setting nodatacow"); + } + } + btrfs_clear_opt(ctx->mount_opt, COMPRESS); + btrfs_clear_opt(ctx->mount_opt, FORCE_COMPRESS); + btrfs_set_opt(ctx->mount_opt, NODATACOW); + btrfs_set_opt(ctx->mount_opt, NODATASUM); + } + break; + case Opt_compress_force: + compress_force = true; + fallthrough; + case Opt_compress: + saved_compress_type = btrfs_test_opt(ctx, COMPRESS) ? + ctx->compress_type : + BTRFS_COMPRESS_NONE; + saved_compress_force = btrfs_test_opt(ctx, FORCE_COMPRESS); + saved_compress_level = ctx->compress_level; + + if (btrfs_param_is_flag(param) || + strncmp(param->string, "zlib", 4) == 0) { + compress_type = "zlib"; + + ctx->compress_type = BTRFS_COMPRESS_ZLIB; + ctx->compress_level = BTRFS_ZLIB_DEFAULT_LEVEL; + /* + * args[0] contains uninitialized data since + * for these tokens we don't expect any + * parameter. + */ + if (!btrfs_param_is_flag(param)) + ctx->compress_level = btrfs_compress_str2level( + BTRFS_COMPRESS_ZLIB, param->string + 4); + btrfs_set_opt(ctx->mount_opt, COMPRESS); + btrfs_clear_opt(ctx->mount_opt, NODATACOW); + btrfs_clear_opt(ctx->mount_opt, NODATASUM); + no_compress = 0; + } else if (strncmp(param->string, "lzo", 3) == 0) { + compress_type = "lzo"; + ctx->compress_type = BTRFS_COMPRESS_LZO; + ctx->compress_level = 0; + btrfs_set_opt(ctx->mount_opt, COMPRESS); + btrfs_clear_opt(ctx->mount_opt, NODATACOW); + btrfs_clear_opt(ctx->mount_opt, NODATASUM); + no_compress = 0; + } else if (strncmp(param->string, "zstd", 4) == 0) { + compress_type = "zstd"; + ctx->compress_type = BTRFS_COMPRESS_ZSTD; + ctx->compress_level = btrfs_compress_str2level( + BTRFS_COMPRESS_ZSTD, param->string + 4); + btrfs_set_opt(ctx->mount_opt, COMPRESS); + btrfs_clear_opt(ctx->mount_opt, NODATACOW); + btrfs_clear_opt(ctx->mount_opt, NODATASUM); + no_compress = 0; + } else if (strncmp(param->string, "no", 2) == 0) { + compress_type = "no"; + ctx->compress_level = 0; + ctx->compress_type = 0; + btrfs_clear_opt(ctx->mount_opt, COMPRESS); + btrfs_clear_opt(ctx->mount_opt, FORCE_COMPRESS); + compress_force = false; + no_compress++; + } else { + btrfs_param_warn(fc, "unrecognized compression value %s", + param->string); + ret = -EINVAL; + break; + } + + if (compress_force) { + btrfs_set_opt(ctx->mount_opt, FORCE_COMPRESS); + } else { + /* + * If we remount from compress-force=xxx to + * compress=xxx, we need clear FORCE_COMPRESS + * flag, otherwise, there is no way for users + * to disable forcible compression separately. + */ + btrfs_clear_opt(ctx->mount_opt, FORCE_COMPRESS); + } + if (no_compress == 1) { + btrfs_param_info(fc, "use no compression"); + } else if ((ctx->compress_type != saved_compress_type) || + (compress_force != saved_compress_force) || + (ctx->compress_level != saved_compress_level)) { + btrfs_param_info(fc, "%s %s compression, level %d", + (compress_force) ? "force" : "use", + compress_type, ctx->compress_level); + } + ctx->has_compression = 1; + compress_force = false; + break; + case Opt_ssd: + if (!result.negated) { + btrfs_param_set_info(fc, ctx, SSD, + "enabling ssd optimizations"); + btrfs_clear_opt(ctx->mount_opt, NOSSD); + } else { + btrfs_set_opt(ctx->mount_opt, NOSSD); + btrfs_param_clear_info(fc, ctx, SSD, + "not using ssd optimizations"); + /* also clear Opt_ssd_spread */ + btrfs_param_clear_info(fc, ctx, SSD_SPREAD, + "not using spread ssd allocation scheme"); + } + break; + case Opt_ssd_spread: + if (!result.negated) { + btrfs_param_set_info(fc, ctx, SSD, + "enabling ssd optimizations"); + btrfs_param_set_info(fc, ctx, SSD_SPREAD, + "using spread ssd allocation scheme"); + btrfs_clear_opt(ctx->mount_opt, NOSSD); + } else { + btrfs_param_clear_info(fc, ctx, SSD_SPREAD, + "not using spread ssd allocation scheme"); + } + break; + case Opt_barrier: + if (!result.negated) + btrfs_param_clear_info(fc, ctx, NOBARRIER, + "turning on barriers"); + else + btrfs_param_set_info(fc, ctx, NOBARRIER, + "turning off barriers"); + break; + case Opt_thread_pool: + if (result.uint_32 == 0) { + btrfs_param_err(fc, "invalid value 0 for thread_pool"); + ret = -EINVAL; + break; + } + ctx->thread_pool_size = result.uint_32; + break; + case Opt_max_inline: + dup = kstrdup(param->string, GFP_KERNEL); + if (!dup) { + ret = -ENOMEM; + break; + } + ctx->has_max_inline = 1; + ctx->max_inline = memparse(dup, NULL); + kfree(dup); + btrfs_param_info(fc, "max_inline at %llu", ctx->max_inline); + break; + case Opt_acl: + if (!result.negated) { +#ifdef CONFIG_BTRFS_FS_POSIX_ACL + fc->sb_flags |= SB_POSIXACL; +#else + btrfs_param_err(err, "support for ACL not compiled in!"); + ret = -EINVAL; +#endif + break; + } + + fc->sb_flags &= ~SB_POSIXACL; + break; + case Opt_treelog: + if (!result.negated) + btrfs_param_clear_info(fc, ctx, NOTREELOG, + "enabling tree log"); + else + btrfs_param_set_info(fc, ctx, NOTREELOG, + "disabling tree log"); + break; + case Opt_norecovery: + fallthrough; + case Opt_nologreplay: + btrfs_param_warn(fc, "'nologreplay' is deprecated, use 'rescue=nologreplay' instead"); + btrfs_param_set_info(fc, ctx, NOLOGREPLAY, + "disabling log replay at mount time"); + break; + case Opt_flushoncommit: + if (!result.negated) + btrfs_param_set_info(fc, ctx, FLUSHONCOMMIT, + "turning on flush-on-commit"); + else + btrfs_param_clear_info(fc, ctx, FLUSHONCOMMIT, + "turning off flush-on-commit"); + break; + case Opt_ratio: + ctx->has_metadata_ratio = 1; + ctx->metadata_ratio = result.uint_32; + btrfs_param_info(fc, "metadata ratio %u", ctx->metadata_ratio); + break; + case Opt_nodiscard: + btrfs_param_clear_info(fc, ctx, DISCARD_SYNC, + "turning off discard"); + btrfs_param_clear_info(fc, ctx, DISCARD_ASYNC, + "turning off async discard"); + btrfs_set_opt(ctx->mount_opt, NODISCARD); + break; + case Opt_discard: + if (btrfs_param_is_flag(param) || + strcmp(param->string, "sync") == 0) { + btrfs_clear_opt(ctx->mount_opt, DISCARD_ASYNC); + btrfs_param_set_info(fc, ctx, DISCARD_SYNC, + "turning on sync discard"); + } else if (strcmp(param->string, "async") == 0) { + btrfs_clear_opt(ctx->mount_opt, DISCARD_SYNC); + btrfs_param_set_info(fc, ctx, DISCARD_ASYNC, + "turning on async discard"); + } else { + btrfs_param_err(fc, "unrecognized discard mode value %s", + param->string); + ret = -EINVAL; + break; + } + btrfs_clear_opt(ctx->mount_opt, NODISCARD); + break; + case Opt_no_space_cache: + ctx->has_space_cache = 1; + ctx->space_cache = BTRFS_FS_CONTEXT_SPACE_CACHE_OFF; + if (btrfs_test_opt(ctx, SPACE_CACHE)) + btrfs_param_clear_info(fc, ctx, SPACE_CACHE, + "disabling disk space caching"); + if (btrfs_test_opt(ctx, FREE_SPACE_TREE)) + btrfs_param_clear_info(fc, ctx, FREE_SPACE_TREE, + "disabling free space tree"); + break; + case Opt_space_cache: + if (btrfs_param_is_flag(param) || + strcmp(param->string, "v1") == 0) { + ctx->has_space_cache = 1; + ctx->space_cache = BTRFS_FS_CONTEXT_SPACE_CACHE_V1; + } else if (strcmp(param->string, "v2") == 0) { + ctx->has_space_cache = 1; + ctx->space_cache = BTRFS_FS_CONTEXT_SPACE_CACHE_V2; + } else { + btrfs_param_err(fc, "unrecognized space_cache value %s", + param->string); + ret = -EINVAL; + break; + } + break; + case Opt_rescan_uuid_tree: + btrfs_set_opt(ctx->mount_opt, RESCAN_UUID_TREE); + break; + case Opt_inode_cache: + btrfs_param_warn(fc, "the 'inode_cache' option is deprecated and has no effect since 5.11"); + break; + case Opt_clear_cache: + ctx->has_clear_cache = 1; + break; + case Opt_user_subvol_rm_allowed: + btrfs_set_opt(ctx->mount_opt, USER_SUBVOL_RM_ALLOWED); + break; + case Opt_enospc_debug: + if (!result.negated) + btrfs_set_opt(ctx->mount_opt, ENOSPC_DEBUG); + else + btrfs_clear_opt(ctx->mount_opt, ENOSPC_DEBUG); + break; + case Opt_defrag: + if (!result.negated) + btrfs_param_set_info(fc, ctx, AUTO_DEFRAG, + "enabling auto defrag"); + else + btrfs_param_clear_info(fc, ctx, AUTO_DEFRAG, + "disabling auto defrag"); + break; + case Opt_recovery: + fallthrough; + case Opt_usebackuproot: + btrfs_param_warn(fc, + "'%s' is deprecated, use 'rescue=usebackuproot' instead", + opt == Opt_recovery ? "recovery" : "usebackuproot"); + btrfs_param_info(fc, "trying to use backup root at mount time"); + btrfs_set_opt(ctx->mount_opt, USEBACKUPROOT); + break; + case Opt_skip_balance: + btrfs_set_opt(ctx->mount_opt, SKIP_BALANCE); + break; +#ifdef CONFIG_BTRFS_FS_CHECK_INTEGRITY + case Opt_check_integrity_including_extent_data: + btrfs_param_info(fc, "enabling check integrity including extent data"); + btrfs_set_opt(ctx->mount_opt, CHECK_INTEGRITY_DATA); + btrfs_set_opt(ctx->mount_opt, CHECK_INTEGRITY); + break; + case Opt_check_integrity: + btrfs_param_info(fc, "enabling check integrity"); + btrfs_set_opt(ctx->mount_opt, CHECK_INTEGRITY); + break; + case Opt_check_integrity_print_mask: + ctx->has_check_integrity_print_mask = 1; + ctx->check_integrity_print_mask = result.uint_32; + btrfs_param_info(fc, "check_integrity_print_mask 0x%x", + ctx->check_integrity_print_mask); + break; +#else + case Opt_check_integrity_including_extent_data: + fallthrough; + case Opt_check_integrity: + fallthrough; + case Opt_check_integrity_print_mask: + btrfs_param_err(fc, "support for check_integrity* not compiled in!"); + ret = -EINVAL; + break; +#endif + case Opt_fatal_errors: + if (strcmp(param->string, "panic") == 0) { + btrfs_set_opt(ctx->mount_opt, PANIC_ON_FATAL_ERROR); + } else if (strcmp(param->string, "bug") == 0) { + btrfs_clear_opt(ctx->mount_opt, PANIC_ON_FATAL_ERROR); + } else { + btrfs_param_err(fc, "unrecognized fatal_errors value %s", + param->string); + ret = -EINVAL; + } + break; + case Opt_commit_interval: + ctx->has_commit_interval = 1; + if (result.uint_32 == 0) { + btrfs_param_info(fc, "using default commit interval %us", + BTRFS_DEFAULT_COMMIT_INTERVAL); + ctx->commit_interval = BTRFS_DEFAULT_COMMIT_INTERVAL; + break; + } + + if (result.uint_32 > 300) + btrfs_param_warn(fc, "excessive commit interval %d", + result.uint_32); + + ctx->commit_interval = result.uint_32; + break; + case Opt_rescue: + switch (result.uint_32) { + case BTRFS_PARAM_RESCUE_USEBACKUPROOT: + btrfs_param_info(fc, "trying to use backup root at mount time"); + btrfs_set_opt(ctx->mount_opt, USEBACKUPROOT); + break; + case BTRFS_PARAM_RESCUE_NOLOGREPLAY: + btrfs_param_set_info(fc, ctx, NOLOGREPLAY, + "disabling log replay at mount time"); + break; + case BTRFS_PARAM_RESCUE_IGNOREBADROOTS: + btrfs_param_set_info(fc, ctx, IGNOREBADROOTS, + "ignoring bad roots"); + break; + case BTRFS_PARAM_RESCUE_IGNOREDATACSUMS: + btrfs_param_set_info(fc, ctx, IGNOREDATACSUMS, + "ignoring data csums"); + break; + case BTRFS_PARAM_RESCUE_RESCUE_ALL: + btrfs_param_info(fc, + "enabling all of the rescue options"); + btrfs_param_set_info(fc, ctx, IGNOREDATACSUMS, + "ignoring data csums"); + btrfs_param_set_info(fc, ctx, IGNOREBADROOTS, + "ignoring bad roots"); + btrfs_param_set_info(fc, ctx, NOLOGREPLAY, + "disabling log replay at mount time"); + break; + default: + /* not reached */ + WARN_ON(true); + ret = -EINVAL; + } + break; +#ifdef CONFIG_BTRFS_DEBUG + case Opt_fragment: + switch (result.uint_32) { + case BTRFS_PARAM_FRAGMENT_DATA: + btrfs_param_info(fc, "fragmenting data"); + btrfs_set_opt(ctx->mount_opt, FRAGMENT_DATA); + break; + case BTRFS_PARAM_FRAGMENT_METADATA: + btrfs_param_info(fc, "fragmenting metadata"); + btrfs_set_opt(ctx->mount_opt, FRAGMENT_METADATA); + break; + case BTRFS_PARAM_FRAGMENT_ALL: + btrfs_param_info(fc, "fragmenting all space"); + btrfs_set_opt(ctx->mount_opt, FRAGMENT_DATA); + btrfs_set_opt(ctx->mount_opt, FRAGMENT_METADATA); + break; + default: + /* not reached */ + WARN_ON(true); + ret = -EINVAL; + } + break; +#endif +#ifdef CONFIG_BTRFS_FS_REF_VERIFY + case Opt_ref_verify: + btrfs_param_info(fc, "doing ref verification"); + btrfs_set_opt(ctx->mount_opt, REF_VERIFY); + break; +#endif + default: + /* We have a bug in the VFS parser. */ + WARN_ON(true); + ret = -EINVAL; + } + + return ret; +} + +static int btrfs_reconfigure(struct fs_context *fc); + +static int btrfs_legacy_reconfigure(struct fs_context *root_fc) +{ + int ret; + struct btrfs_fs_context *ctx = root_fc->fs_private; + struct vfsmount *root_mnt = ctx->root_mnt; + + root_fc->sb_flags &= ~SB_RDONLY; + down_write(&root_mnt->mnt_sb->s_umount); + ret = btrfs_reconfigure(root_fc); + up_write(&root_mnt->mnt_sb->s_umount); + return ret; +} + +static int get_default_subvol_objectid(struct btrfs_fs_info *fs_info, u64 *objectid) +{ + struct btrfs_root *root = fs_info->tree_root; + struct btrfs_dir_item *di; + struct btrfs_path *path; + struct btrfs_key location; + struct fscrypt_str name = FSTR_INIT("default", 7); + u64 dir_id; + + path = btrfs_alloc_path(); + if (!path) + return -ENOMEM; + + /* + * Find the "default" dir item which points to the root item that we + * will mount by default if we haven't been given a specific subvolume + * to mount. + */ + dir_id = btrfs_super_root_dir(fs_info->super_copy); + di = btrfs_lookup_dir_item(NULL, root, path, dir_id, &name, 0); + if (IS_ERR(di)) { + btrfs_free_path(path); + return PTR_ERR(di); + } + if (!di) { + /* + * Ok the default dir item isn't there. This is weird since + * it's always been there, but don't freak out, just try and + * mount the top-level subvolume. + */ + btrfs_free_path(path); + *objectid = BTRFS_FS_TREE_OBJECTID; + return 0; + } + + btrfs_dir_item_key_to_cpu(path->nodes[0], di, &location); + btrfs_free_path(path); + *objectid = location.objectid; + return 0; +} + +/* + * subvolumes are identified by ino 256 + */ +static inline int is_subvolume_inode(struct inode *inode) +{ + if (inode && inode->i_ino == BTRFS_FIRST_FREE_OBJECTID) + return 1; + return 0; +} + +static struct dentry *mount_subvol(struct fs_context *fc) +{ + struct btrfs_fs_context *ctx = fc->fs_private; + struct super_block *s = ctx->root_mnt->mnt_sb; + struct btrfs_fs_info *fs_info = btrfs_sb(s); + struct inode *root_inode; + u64 root_objectid; + struct dentry *root; + int ret; + + if (WARN_ON(ctx->phase != BTRFS_FS_CONTEXT_SUBTREE)) + return ERR_PTR(-EINVAL); + + if (!ctx->subvol_name) { + if (!ctx->subvol_id) { + ret = get_default_subvol_objectid(fs_info, + &ctx->subvol_id); + if (ret) + return ERR_PTR(ret); + } + ctx->subvol_name = btrfs_get_subvol_name_from_objectid( + fs_info, ctx->subvol_id); + if (IS_ERR(ctx->subvol_name)) { + root = ERR_CAST(ctx->subvol_name); + ctx->subvol_name = NULL; + return root; + } + + } + + root = mount_subtree(ctx->root_mnt, ctx->subvol_name); + ctx->root_mnt = NULL; /* @ctx->root_mnt has been consumed */ + if (IS_ERR(root)) + return root; + + root_inode = d_inode(root); + root_objectid = BTRFS_I(root_inode)->root->root_key.objectid; + + ret = 0; + if (!is_subvolume_inode(root_inode)) { + btrfs_err(fs_info, "'%s' is not a valid subvolume", + ctx->subvol_name); + ret = -EINVAL; + } + if (ctx->subvol_id && root_objectid != ctx->subvol_id) { + /* + * This will also catch a race condition where a + * subvolume which was passed by ID is renamed and + * another subvolume is renamed over the old location. + */ + btrfs_err(fs_info, "subvol '%s' does not match subvolid %llu", + ctx->subvol_name, ctx->subvol_id); + ret = -EINVAL; + } + if (ret) { + dput(root); + root = ERR_PTR(ret); + /* + * On successful mount_subtree() we'll trade vfsmount + * reference for a super block reference and will have + * locked the super block again after fc_mount() + * unlocked it. + */ + deactivate_locked_super(s); + } + + return root; +} + +static int btrfs_get_tree_common(struct fs_context *fc) +{ + struct vfsmount *root_mnt = NULL; + struct fs_context *root_fc; + struct dentry *root_dentry; + struct btrfs_fs_context *ctx = fc->fs_private; + int ret; + + if (WARN_ON(ctx->phase != BTRFS_FS_CONTEXT_PREPARE)) + return -EINVAL; + + root_fc = vfs_dup_fs_context(fc); + if (IS_ERR(root_fc)) + return PTR_ERR(root_fc); + + /* + * We've duplicated the security mount options above and we only + * need them to be set when we really create a new superblock. + * They're irrelevant when we mount the subvolume as the + * superblock does already exist at that point. So free the + * security blob here. + */ + security_free_mnt_opts(&fc->security); + fc->security = NULL; + + /* Create the superblock so we can mount a subtree later. */ + ctx->phase = BTRFS_FS_CONTEXT_SUPER; + + root_mnt = fc_mount(root_fc); + if (PTR_ERR_OR_ZERO(root_mnt) == -EBUSY) { + bool ro2rw = !(root_fc->sb_flags & SB_RDONLY); + + if (ro2rw) + root_fc->sb_flags |= SB_RDONLY; + else + root_fc->sb_flags &= ~SB_RDONLY; + + root_mnt = fc_mount(root_fc); + if (IS_ERR(root_mnt)) { + put_fs_context(root_fc); + return PTR_ERR(root_mnt); + } + ctx->root_mnt = root_mnt; + + /* + * Ever since commit 0723a0473fb4 ("btrfs: allow + * mounting btrfs subvolumes with different ro/rw + * options") the following works: + * + * (i) mount /dev/sda3 -o subvol=foo,ro /mnt/foo + * (ii) mount /dev/sda3 -o subvol=bar,rw /mnt/bar + * + * which looks nice and innocent but is actually pretty + * intricate and deserves a long comment. + * + * On another filesystem a subvolume mount is close to + * something like: + * + * (iii) # create rw superblock + initial mount + * mount -t xfs /dev/sdb /opt/ + * + * # create ro bind mount + * mount --bind -o ro /opt/foo /mnt/foo + * + * # unmount initial mount + * umount /opt + * + * Of course, there's some special subvolume sauce and + * there's the fact that the sb->s_root dentry is really + * swapped after mount_subtree(). But conceptually it's + * very close and will help us understand the issue. + * + * The old mount api didn't cleanly distinguish between + * a mount being made ro and a superblock being made ro. + * The only way to change the ro state of either object + * was by passing MS_RDONLY. If a new mount was created + * via mount(2) such as: + * + * mount("/dev/sdb", "/mnt", "xfs", MS_RDONLY, NULL); + * + * the MS_RDONLY flag being specified had two effects: + * + * (1) MNT_READONLY was raised -> the resulting mount + * got @mnt->mnt_flags |= MNT_READONLY raised. + * + * (2) MS_RDONLY was passed to the filesystem's mount + * method and the filesystems made the superblock + * ro. Note, how SB_RDONLY has the same value as + * MS_RDONLY and is raised whenever MS_RDONLY is + * passed through mount(2). + * + * Creating a subtree mount via (iii) ends up leaving a + * rw superblock with a subtree mounted ro. + * + * But consider the effect on the old mount api on btrfs + * subvolume mounting which combines the distinct step + * in (iii) into a a single step. + * + * By issuing (i) both the mount and the superblock are + * turned ro. Now when (ii) is issued the superblock is + * ro and thus even if the mount created for (ii) is rw + * it wouldn't help. Hence, btrfs needed to transition + * the superblock from ro to rw for (ii) which it did + * using an internal remount call (a bold choice...). + * + * IOW, subvolume mounting was inherently messy due to + * the ambiguity of MS_RDONLY in mount(2). Note, this + * ambiguity has mount(8) always translate "ro" to + * MS_RDONLY. IOW, in both (i) and (ii) "ro" becomes + * MS_RDONLY when passed by mount(8) to mount(2). + * + * Enter the new mount api. The new mount api + * disambiguates making a mount ro and making a + * superblock ro. + * + * (3) To turn a mount ro the MOUNT_ATTR_RDONLY flag can + * be used with either fsmount() or mount_setattr(). + * This is a pure VFS level change for a specific + * mount or mount tree that is never seen by the + * filesystem itself. + * + * (4) To turn a superblock ro the "ro" flag must be + * used with fsconfig(FSCONFIG_SET_FLAG, "ro"). This + * option is seen by the filesytem in fc->sb_flags. + * + * This disambiguation has rather positive consequences. + * Mounting a subvolume ro will not also turn the + * superblock ro. Only the mount for the subvolume will + * become ro. + * + * So, if the superblock creation request comes from the + * new mount api the caller must've explicitly done: + * + * fsconfig(FSCONFIG_SET_FLAG, "ro") + * fsmount/mount_setattr(MOUNT_ATTR_RDONLY) + * + * IOW, at some point the caller must have explicitly + * turned the whole superblock ro and we shouldn't just + * undo it like we did for the old mount api. In any + * case, it lets us avoid this nasty hack in the new + * mount api. + * + * Consequently, the remounting hack must only be used + * for requests originating from the old mount api and + * should be marked for full deprecation so it can be + * turned off in a couple of years. + * + * The new mount api has no reason to support this hack. + */ + if (root_fc->oldapi && ro2rw) { + /* + * This magic internal remount is a pretty bold + * move as the VFS reserves the right to protect + * ro->rw transitions on the VFS layer similar + * to how it protects rw->ro transitions. + */ + ret = btrfs_legacy_reconfigure(root_fc); + if (ret) + root_mnt = ERR_PTR(ret); + } + } + put_fs_context(root_fc); + if (IS_ERR(root_mnt)) + return PTR_ERR(root_mnt); + ctx->root_mnt = root_mnt; + + root_dentry = mount_subvol(fc); + if (IS_ERR(root_dentry)) + return PTR_ERR(root_dentry); + + fc->root = root_dentry; + return 0; +} + +static int btrfs_test_super(struct super_block *s, struct fs_context *fc) +{ + struct btrfs_fs_info *p = fc->s_fs_info; + struct btrfs_fs_info *fs_info = btrfs_sb(s); + + return fs_info->fs_devices == p->fs_devices; +} + +static int btrfs_set_super(struct super_block *s, struct fs_context *fc) +{ + return set_anon_super_fc(s, fc->s_fs_info); +} + +static int btrfs_get_tree_super(struct fs_context *fc) +{ + struct btrfs_fs_context *ctx = fc->fs_private; + struct btrfs_fs_info *fs_info = fc->s_fs_info; + struct block_device *bdev = NULL; + struct super_block *s; + struct btrfs_device *device = NULL; + struct btrfs_fs_devices *fs_devices = NULL; + blk_mode_t mode = sb_open_mode(fc->sb_flags); + int error = 0; + + if (WARN_ON(ctx->phase != BTRFS_FS_CONTEXT_SUPER)) + return -EINVAL; + + fs_info->super_copy = kzalloc(BTRFS_SUPER_INFO_SIZE, GFP_KERNEL); + fs_info->super_for_commit = kzalloc(BTRFS_SUPER_INFO_SIZE, GFP_KERNEL); + if (!fs_info->super_copy || !fs_info->super_for_commit) + return -ENOMEM; + + mutex_lock(&uuid_mutex); + + for (size_t nr = 0; nr < ctx->nr; nr++) { + device = btrfs_scan_one_device(ctx->device_paths[nr], mode); + if (IS_ERR(device)) { + mutex_unlock(&uuid_mutex); + return -ENOMEM; + } + } + + device = btrfs_scan_one_device(fc->source, mode); + if (IS_ERR(device)) { + mutex_unlock(&uuid_mutex); + return PTR_ERR(device); + } + + fs_devices = device->fs_devices; + fs_info->fs_devices = fs_devices; + + error = btrfs_open_devices(fs_devices, mode, &btrfs_fs_type); + mutex_unlock(&uuid_mutex); + if (error) + return error; + + if (!(fc->sb_flags & SB_RDONLY) && fs_devices->rw_devices == 0) { + error = -EACCES; + goto error_close_devices; + } + + bdev = fs_devices->latest_dev->bdev; + + fc->sb_flags |= SB_NOSEC; + /* + * If a new superblock is allocated then fc->s_fs_info will have + * been transfered to sb->s_fs_info and will be cleaned up by + * ->kill_sb() if we fail afterwards. + * + * If no matching or an existing superblock is found + * fc->s_fs_info will be left alone and cleaned up during + * btrfs_free(). + */ + s = sget_fc(fc, btrfs_test_super, btrfs_set_super); + if (IS_ERR(s)) { + error = PTR_ERR(s); + goto error_close_devices; + } + + if (s->s_root) { + btrfs_close_devices(fs_devices); + if ((fc->sb_flags ^ s->s_flags) & SB_RDONLY) + error = -EBUSY; + } else { + snprintf(s->s_id, sizeof(s->s_id), "%pg", bdev); + shrinker_debugfs_rename(&s->s_shrink, "sb-%s:%s", btrfs_fs_type.name, + s->s_id); + btrfs_sb(s)->bdev_holder = &btrfs_fs_type; + error = btrfs_fill_super(fc, s, fs_devices); + } + if (error) { + /* we can rely on @fs_devices having been closed */ + deactivate_locked_super(s); + return error; + } + + fc->root = dget(s->s_root); + ctx->phase = BTRFS_FS_CONTEXT_SUBTREE; + return 0; + +error_close_devices: + btrfs_close_devices(fs_devices); + return error; +} + +int btrfs_get_tree(struct fs_context *fc) +{ + struct btrfs_fs_context *ctx = fc->fs_private; + + if (ctx->phase == BTRFS_FS_CONTEXT_SUPER) + return btrfs_get_tree_super(fc); + + return btrfs_get_tree_common(fc); +} + +static int btrfs_dup_fs_context(struct fs_context *fc, struct fs_context *src_fc) +{ + struct btrfs_fs_context *ctx = src_fc->fs_private; + struct btrfs_fs_info *fs_info; + + /* + * Setup a dummy root and fs_info for test/set super. This is + * because we don't actually fill this stuff out until + * open_ctree, but we need then open_ctree will properly + * initialize the file system specific settings later. + * btrfs_init_fs_info initializes the static elements of the + * fs_info (locks and such) to make cleanup easier if we find a + * superblock with our given fs_devices later on at sget_fc() + * time. + */ + fs_info = kvzalloc(sizeof(struct btrfs_fs_info), GFP_KERNEL); + if (!fs_info) + return -ENOMEM; + btrfs_init_fs_info(fs_info); + + refcount_inc(&ctx->refs); + + /* + * Steal the fs_context::source from original context. We only + * need it to create the superblock, but not for the subtree. + */ + fc->source = src_fc->source; + src_fc->source = NULL; + fc->fs_private = ctx; + fc->s_fs_info = fs_info; + + return 0; +} + +static inline void btrfs_free_fs_context_private(struct btrfs_fs_context *ctx) +{ + if (refcount_dec_and_test(&ctx->refs)) { + mntput(ctx->root_mnt); + btrfs_parse_param_drop_devices(ctx); + kfree(ctx->subvol_name); + kfree(ctx); + } +} + +static void btrfs_free_fs_context(struct fs_context *fc) +{ + struct btrfs_fs_context *ctx = fc->fs_private; + struct btrfs_fs_info *fs_info = fc->s_fs_info; + + if (ctx) + btrfs_free_fs_context_private(ctx); + + if (fs_info) + btrfs_free_fs_info(fs_info); +} + +static inline void btrfs_remount_begin(struct btrfs_fs_info *fs_info, + unsigned long old_opts, int flags) +{ + if (btrfs_raw_test_opt(old_opts, AUTO_DEFRAG) && + (!btrfs_raw_test_opt(fs_info->mount_opt, AUTO_DEFRAG) || + (flags & SB_RDONLY))) { + /* wait for any defraggers to finish */ + wait_event(fs_info->transaction_wait, + (atomic_read(&fs_info->defrag_running) == 0)); + if (flags & SB_RDONLY) + sync_filesystem(fs_info->sb); + } +} + +static inline void btrfs_remount_cleanup(struct btrfs_fs_info *fs_info, + unsigned long old_opts) +{ + const bool cache_opt = btrfs_test_opt(fs_info, SPACE_CACHE); + + /* + * We need to cleanup all defragable inodes if the autodefragment is + * close or the filesystem is read only. + */ + if (btrfs_raw_test_opt(old_opts, AUTO_DEFRAG) && + (!btrfs_raw_test_opt(fs_info->mount_opt, AUTO_DEFRAG) || sb_rdonly(fs_info->sb))) { + btrfs_cleanup_defrag_inodes(fs_info); + } + + /* If we toggled discard async */ + if (!btrfs_raw_test_opt(old_opts, DISCARD_ASYNC) && + btrfs_test_opt(fs_info, DISCARD_ASYNC)) + btrfs_discard_resume(fs_info); + else if (btrfs_raw_test_opt(old_opts, DISCARD_ASYNC) && + !btrfs_test_opt(fs_info, DISCARD_ASYNC)) + btrfs_discard_cleanup(fs_info); + + /* If we toggled space cache */ + if (cache_opt != btrfs_free_space_cache_v1_active(fs_info)) + btrfs_set_free_space_cache_v1_active(fs_info, cache_opt); +} + +static void btrfs_resize_thread_pool(struct btrfs_fs_info *fs_info, + u32 new_pool_size, u32 old_pool_size) +{ + if (new_pool_size == old_pool_size) + return; + + fs_info->thread_pool_size = new_pool_size; + + btrfs_info(fs_info, "resize thread pool %d -> %d", + old_pool_size, new_pool_size); + + btrfs_workqueue_set_max(fs_info->workers, new_pool_size); + btrfs_workqueue_set_max(fs_info->hipri_workers, new_pool_size); + btrfs_workqueue_set_max(fs_info->delalloc_workers, new_pool_size); + btrfs_workqueue_set_max(fs_info->caching_workers, new_pool_size); + workqueue_set_max_active(fs_info->endio_workers, new_pool_size); + workqueue_set_max_active(fs_info->endio_meta_workers, new_pool_size); + btrfs_workqueue_set_max(fs_info->endio_write_workers, new_pool_size); + btrfs_workqueue_set_max(fs_info->endio_freespace_worker, new_pool_size); + btrfs_workqueue_set_max(fs_info->delayed_workers, new_pool_size); +} + +static int btrfs_reconfigure(struct fs_context *fc) +{ + struct btrfs_fs_context *ctx = fc->fs_private; + struct super_block *sb = fc->root->d_sb; + struct btrfs_fs_info *fs_info = btrfs_sb(sb); + unsigned old_flags = sb->s_flags; + unsigned long old_opts = fs_info->mount_opt; + unsigned long old_compress_type = fs_info->compress_type; + u64 old_max_inline = fs_info->max_inline; + u32 old_thread_pool_size = fs_info->thread_pool_size; + u32 old_metadata_ratio = fs_info->metadata_ratio; + int ret = 0; + + sync_filesystem(sb); + set_bit(BTRFS_FS_STATE_REMOUNTING, &fs_info->fs_state); + + /* + * If ctx->phase is BTRFS_FS_CONTEXT_SUPER we've just created or + * gotten a reference on a superblock immediately followed by an + * internal remount. That can only happen for the old mount api. + */ + if (ctx->phase != BTRFS_FS_CONTEXT_SUPER) + ret = btrfs_fs_params_verify(fs_info, fc); + else if (WARN_ON(!fc->oldapi)) + ret = -EINVAL; + if (ret) + goto restore; + + ret = btrfs_check_features(fs_info, !(fc->sb_flags & SB_RDONLY)); + if (ret < 0) + goto restore; + + btrfs_remount_begin(fs_info, old_opts, fc->sb_flags); + btrfs_resize_thread_pool(fs_info, fs_info->thread_pool_size, + old_thread_pool_size); + + if ((bool)btrfs_test_opt(fs_info, FREE_SPACE_TREE) != + (bool)btrfs_fs_compat_ro(fs_info, FREE_SPACE_TREE) && + (!sb_rdonly(sb) || (fc->sb_flags & SB_RDONLY))) { + btrfs_param_warn(fc, + "remount supports changing free space tree only from ro to rw"); + /* Make sure free space cache options match the state on disk */ + if (btrfs_fs_compat_ro(fs_info, FREE_SPACE_TREE)) { + btrfs_set_opt(fs_info->mount_opt, FREE_SPACE_TREE); + btrfs_clear_opt(fs_info->mount_opt, SPACE_CACHE); + } + if (btrfs_free_space_cache_v1_active(fs_info)) { + btrfs_clear_opt(fs_info->mount_opt, FREE_SPACE_TREE); + btrfs_set_opt(fs_info->mount_opt, SPACE_CACHE); + } + } + + if ((bool)(fc->sb_flags & SB_RDONLY) == sb_rdonly(sb)) + goto out; + + if (fc->sb_flags & SB_RDONLY) { + /* + * this also happens on 'umount -rf' or on shutdown, when + * the filesystem is busy. + */ + cancel_work_sync(&fs_info->async_reclaim_work); + cancel_work_sync(&fs_info->async_data_reclaim_work); + + btrfs_discard_cleanup(fs_info); + + /* wait for the uuid_scan task to finish */ + down(&fs_info->uuid_tree_rescan_sem); + /* avoid complains from lockdep et al. */ + up(&fs_info->uuid_tree_rescan_sem); + + btrfs_set_sb_rdonly(sb); + + /* + * Setting SB_RDONLY will put the cleaner thread to + * sleep at the next loop if it's already active. + * If it's already asleep, we'll leave unused block + * groups on disk until we're mounted read-write again + * unless we clean them up here. + */ + btrfs_delete_unused_bgs(fs_info); + + /* + * The cleaner task could be already running before we set the + * flag BTRFS_FS_STATE_RO (and SB_RDONLY in the superblock). + * We must make sure that after we finish the remount, i.e. after + * we call btrfs_commit_super(), the cleaner can no longer start + * a transaction - either because it was dropping a dead root, + * running delayed iputs or deleting an unused block group (the + * cleaner picked a block group from the list of unused block + * groups before we were able to in the previous call to + * btrfs_delete_unused_bgs()). + */ + wait_on_bit(&fs_info->flags, BTRFS_FS_CLEANER_RUNNING, + TASK_UNINTERRUPTIBLE); + + /* + * We've set the superblock to RO mode, so we might have made + * the cleaner task sleep without running all pending delayed + * iputs. Go through all the delayed iputs here, so that if an + * unmount happens without remounting RW we don't end up at + * finishing close_ctree() with a non-empty list of delayed + * iputs. + */ + btrfs_run_delayed_iputs(fs_info); + + btrfs_dev_replace_suspend_for_unmount(fs_info); + btrfs_scrub_cancel(fs_info); + btrfs_pause_balance(fs_info); + + /* + * Pause the qgroup rescan worker if it is running. We don't want + * it to be still running after we are in RO mode, as after that, + * by the time we unmount, it might have left a transaction open, + * so we would leak the transaction and/or crash. + */ + btrfs_qgroup_wait_for_completion(fs_info, false); + + ret = btrfs_commit_super(fs_info); + if (ret) + goto restore; + } else { + if (BTRFS_FS_ERROR(fs_info)) { + btrfs_err(fs_info, + "Remounting read-write after error is not allowed"); + ret = -EINVAL; + goto restore; + } + if (fs_info->fs_devices->rw_devices == 0) { + ret = -EACCES; + goto restore; + } + + if (!btrfs_check_rw_degradable(fs_info, NULL)) { + btrfs_param_warn( + fc, + "too many missing devices, writable remount is not allowed"); + ret = -EACCES; + goto restore; + } + + if (btrfs_super_log_root(fs_info->super_copy) != 0) { + btrfs_param_warn( + fc, + "mount required to replay tree-log, cannot remount read-write"); + ret = -EINVAL; + goto restore; + } + + /* + * NOTE: when remounting with a change that does writes, don't + * put it anywhere above this point, as we are not sure to be + * safe to write until we pass the above checks. + */ + ret = btrfs_start_pre_rw_mount(fs_info); + if (ret) + goto restore; + + btrfs_clear_sb_rdonly(sb); + + set_bit(BTRFS_FS_OPEN, &fs_info->flags); + } +out: + + if (fc->sb_flags & SB_POSIXACL) + sb->s_flags |= SB_POSIXACL; + else + sb->s_flags &= ~SB_POSIXACL; + + wake_up_process(fs_info->transaction_kthread); + btrfs_remount_cleanup(fs_info, old_opts); + btrfs_clear_oneshot_options(fs_info); + clear_bit(BTRFS_FS_STATE_REMOUNTING, &fs_info->fs_state); + + return 0; + +restore: + /* We've hit an error - don't reset SB_RDONLY */ + if (sb_rdonly(sb)) + old_flags |= SB_RDONLY; + if (!(old_flags & SB_RDONLY)) + clear_bit(BTRFS_FS_STATE_RO, &fs_info->fs_state); + sb->s_flags = old_flags; + fs_info->mount_opt = old_opts; + fs_info->compress_type = old_compress_type; + fs_info->max_inline = old_max_inline; + btrfs_resize_thread_pool(fs_info, + old_thread_pool_size, fs_info->thread_pool_size); + fs_info->metadata_ratio = old_metadata_ratio; + btrfs_remount_cleanup(fs_info, old_opts); + clear_bit(BTRFS_FS_STATE_REMOUNTING, &fs_info->fs_state); + + return ret; +} + +static const struct fs_context_operations btrfs_context_ops = { + .parse_param = btrfs_parse_param, + .get_tree = btrfs_get_tree, + .reconfigure = btrfs_reconfigure, + .free = btrfs_free_fs_context, + .dup = btrfs_dup_fs_context, +}; + +int btrfs_init_fs_context(struct fs_context *fc) +{ + struct btrfs_fs_context *ctx; + + ctx = kzalloc(sizeof(struct btrfs_fs_context), GFP_KERNEL); + if (!ctx) + return -ENOMEM; + refcount_set(&ctx->refs, 1); + ctx->phase = BTRFS_FS_CONTEXT_PREPARE; + + /* + * If this is a remount make sure that we copy the current mount + * options into @ctx so checking for current options during + * parameter parsing is identical for both remount and a regular + * mount. + */ + if (fc->purpose == FS_CONTEXT_FOR_RECONFIGURE) + btrfs_fs_info_to_context(ctx, btrfs_sb(fc->root->d_sb)); + else + ctx->compress_type = BTRFS_COMPRESS_ZLIB; + +#ifdef CONFIG_BTRFS_FS_POSIX_ACL + fc->sb_flags |= SB_POSIXACL; + fc->sb_flags |= SB_I_VERSION; +#endif + fc->fs_private = ctx; + fc->ops = &btrfs_context_ops; + return 0; +} diff --git a/fs/btrfs/params.h b/fs/btrfs/params.h new file mode 100644 index 000000000000..85ccaa4a660f --- /dev/null +++ b/fs/btrfs/params.h @@ -0,0 +1,21 @@ +// SPDX-License-Identifier: GPL-2.0 +/* + * Copyright (C) 2023 Christian Brauner. + */ + +#ifndef BTRFS_FS_CONTEXT_H +#define BTRFS_FS_CONTEXT_H + +#include +#include +#include +#include +#include "fs.h" + +extern const struct fs_parameter_spec btrfs_parameter_spec[]; + +int btrfs_fs_params_verify(struct btrfs_fs_info *info, struct fs_context *fc); +int btrfs_get_tree(struct fs_context *fc); +int btrfs_init_fs_context(struct fs_context *fc); + +#endif diff --git a/fs/btrfs/super.c b/fs/btrfs/super.c index 1c3c1d7ad68c..65172cfdad22 100644 --- a/fs/btrfs/super.c +++ b/fs/btrfs/super.c @@ -59,905 +59,17 @@ #include "verity.h" #include "super.h" #include "extent-tree.h" +#include "params.h" #define CREATE_TRACE_POINTS #include static const struct super_operations btrfs_super_ops; -/* - * Types for mounting the default subvolume and a subvolume explicitly - * requested by subvol=/path. That way the callchain is straightforward and we - * don't have to play tricks with the mount options and recursive calls to - * btrfs_mount. - * - * The new btrfs_root_fs_type also servers as a tag for the bdev_holder. - */ -static struct file_system_type btrfs_fs_type; -static struct file_system_type btrfs_root_fs_type; - -static int btrfs_remount(struct super_block *sb, int *flags, char *data); - static void btrfs_put_super(struct super_block *sb) { close_ctree(btrfs_sb(sb)); } -enum { - Opt_acl, Opt_noacl, - Opt_clear_cache, - Opt_commit_interval, - Opt_compress, - Opt_compress_force, - Opt_compress_force_type, - Opt_compress_type, - Opt_degraded, - Opt_device, - Opt_fatal_errors, - Opt_flushoncommit, Opt_noflushoncommit, - Opt_max_inline, - Opt_barrier, Opt_nobarrier, - Opt_datacow, Opt_nodatacow, - Opt_datasum, Opt_nodatasum, - Opt_defrag, Opt_nodefrag, - Opt_discard, Opt_nodiscard, - Opt_discard_mode, - Opt_norecovery, - Opt_ratio, - Opt_rescan_uuid_tree, - Opt_skip_balance, - Opt_space_cache, Opt_no_space_cache, - Opt_space_cache_version, - Opt_ssd, Opt_nossd, - Opt_ssd_spread, Opt_nossd_spread, - Opt_subvol, - Opt_subvol_empty, - Opt_subvolid, - Opt_thread_pool, - Opt_treelog, Opt_notreelog, - Opt_user_subvol_rm_allowed, - - /* Rescue options */ - Opt_rescue, - Opt_usebackuproot, - Opt_nologreplay, - Opt_ignorebadroots, - Opt_ignoredatacsums, - Opt_rescue_all, - - /* Deprecated options */ - Opt_recovery, - Opt_inode_cache, Opt_noinode_cache, - - /* Debugging options */ - Opt_check_integrity, - Opt_check_integrity_including_extent_data, - Opt_check_integrity_print_mask, - Opt_enospc_debug, Opt_noenospc_debug, -#ifdef CONFIG_BTRFS_DEBUG - Opt_fragment_data, Opt_fragment_metadata, Opt_fragment_all, -#endif -#ifdef CONFIG_BTRFS_FS_REF_VERIFY - Opt_ref_verify, -#endif - Opt_err, -}; - -static const match_table_t tokens = { - {Opt_acl, "acl"}, - {Opt_noacl, "noacl"}, - {Opt_clear_cache, "clear_cache"}, - {Opt_commit_interval, "commit=%u"}, - {Opt_compress, "compress"}, - {Opt_compress_type, "compress=%s"}, - {Opt_compress_force, "compress-force"}, - {Opt_compress_force_type, "compress-force=%s"}, - {Opt_degraded, "degraded"}, - {Opt_device, "device=%s"}, - {Opt_fatal_errors, "fatal_errors=%s"}, - {Opt_flushoncommit, "flushoncommit"}, - {Opt_noflushoncommit, "noflushoncommit"}, - {Opt_inode_cache, "inode_cache"}, - {Opt_noinode_cache, "noinode_cache"}, - {Opt_max_inline, "max_inline=%s"}, - {Opt_barrier, "barrier"}, - {Opt_nobarrier, "nobarrier"}, - {Opt_datacow, "datacow"}, - {Opt_nodatacow, "nodatacow"}, - {Opt_datasum, "datasum"}, - {Opt_nodatasum, "nodatasum"}, - {Opt_defrag, "autodefrag"}, - {Opt_nodefrag, "noautodefrag"}, - {Opt_discard, "discard"}, - {Opt_discard_mode, "discard=%s"}, - {Opt_nodiscard, "nodiscard"}, - {Opt_norecovery, "norecovery"}, - {Opt_ratio, "metadata_ratio=%u"}, - {Opt_rescan_uuid_tree, "rescan_uuid_tree"}, - {Opt_skip_balance, "skip_balance"}, - {Opt_space_cache, "space_cache"}, - {Opt_no_space_cache, "nospace_cache"}, - {Opt_space_cache_version, "space_cache=%s"}, - {Opt_ssd, "ssd"}, - {Opt_nossd, "nossd"}, - {Opt_ssd_spread, "ssd_spread"}, - {Opt_nossd_spread, "nossd_spread"}, - {Opt_subvol, "subvol=%s"}, - {Opt_subvol_empty, "subvol="}, - {Opt_subvolid, "subvolid=%s"}, - {Opt_thread_pool, "thread_pool=%u"}, - {Opt_treelog, "treelog"}, - {Opt_notreelog, "notreelog"}, - {Opt_user_subvol_rm_allowed, "user_subvol_rm_allowed"}, - - /* Rescue options */ - {Opt_rescue, "rescue=%s"}, - /* Deprecated, with alias rescue=nologreplay */ - {Opt_nologreplay, "nologreplay"}, - /* Deprecated, with alias rescue=usebackuproot */ - {Opt_usebackuproot, "usebackuproot"}, - - /* Deprecated options */ - {Opt_recovery, "recovery"}, - - /* Debugging options */ - {Opt_check_integrity, "check_int"}, - {Opt_check_integrity_including_extent_data, "check_int_data"}, - {Opt_check_integrity_print_mask, "check_int_print_mask=%u"}, - {Opt_enospc_debug, "enospc_debug"}, - {Opt_noenospc_debug, "noenospc_debug"}, -#ifdef CONFIG_BTRFS_DEBUG - {Opt_fragment_data, "fragment=data"}, - {Opt_fragment_metadata, "fragment=metadata"}, - {Opt_fragment_all, "fragment=all"}, -#endif -#ifdef CONFIG_BTRFS_FS_REF_VERIFY - {Opt_ref_verify, "ref_verify"}, -#endif - {Opt_err, NULL}, -}; - -static const match_table_t rescue_tokens = { - {Opt_usebackuproot, "usebackuproot"}, - {Opt_nologreplay, "nologreplay"}, - {Opt_ignorebadroots, "ignorebadroots"}, - {Opt_ignorebadroots, "ibadroots"}, - {Opt_ignoredatacsums, "ignoredatacsums"}, - {Opt_ignoredatacsums, "idatacsums"}, - {Opt_rescue_all, "all"}, - {Opt_err, NULL}, -}; - -static bool check_ro_option(struct btrfs_fs_info *fs_info, unsigned long opt, - const char *opt_name) -{ - if (fs_info->mount_opt & opt) { - btrfs_err(fs_info, "%s must be used with ro mount option", - opt_name); - return true; - } - return false; -} - -static int parse_rescue_options(struct btrfs_fs_info *info, const char *options) -{ - char *opts; - char *orig; - char *p; - substring_t args[MAX_OPT_ARGS]; - int ret = 0; - - opts = kstrdup(options, GFP_KERNEL); - if (!opts) - return -ENOMEM; - orig = opts; - - while ((p = strsep(&opts, ":")) != NULL) { - int token; - - if (!*p) - continue; - token = match_token(p, rescue_tokens, args); - switch (token){ - case Opt_usebackuproot: - btrfs_info(info, - "trying to use backup root at mount time"); - btrfs_set_opt(info->mount_opt, USEBACKUPROOT); - break; - case Opt_nologreplay: - btrfs_set_and_info(info, NOLOGREPLAY, - "disabling log replay at mount time"); - break; - case Opt_ignorebadroots: - btrfs_set_and_info(info, IGNOREBADROOTS, - "ignoring bad roots"); - break; - case Opt_ignoredatacsums: - btrfs_set_and_info(info, IGNOREDATACSUMS, - "ignoring data csums"); - break; - case Opt_rescue_all: - btrfs_info(info, "enabling all of the rescue options"); - btrfs_set_and_info(info, IGNOREDATACSUMS, - "ignoring data csums"); - btrfs_set_and_info(info, IGNOREBADROOTS, - "ignoring bad roots"); - btrfs_set_and_info(info, NOLOGREPLAY, - "disabling log replay at mount time"); - break; - case Opt_err: - btrfs_info(info, "unrecognized rescue option '%s'", p); - ret = -EINVAL; - goto out; - default: - break; - } - - } -out: - kfree(orig); - return ret; -} - -/* - * Regular mount options parser. Everything that is needed only when - * reading in a new superblock is parsed here. - * XXX JDM: This needs to be cleaned up for remount. - */ -int btrfs_parse_options(struct btrfs_fs_info *info, char *options, - unsigned long new_flags) -{ - substring_t args[MAX_OPT_ARGS]; - char *p, *num; - int intarg; - int ret = 0; - char *compress_type; - bool compress_force = false; - enum btrfs_compression_type saved_compress_type; - int saved_compress_level; - bool saved_compress_force; - int no_compress = 0; - const bool remounting = test_bit(BTRFS_FS_STATE_REMOUNTING, &info->fs_state); - - if (btrfs_fs_compat_ro(info, FREE_SPACE_TREE)) - btrfs_set_opt(info->mount_opt, FREE_SPACE_TREE); - else if (btrfs_free_space_cache_v1_active(info)) { - if (btrfs_is_zoned(info)) { - btrfs_info(info, - "zoned: clearing existing space cache"); - btrfs_set_super_cache_generation(info->super_copy, 0); - } else { - btrfs_set_opt(info->mount_opt, SPACE_CACHE); - } - } - - /* - * Even the options are empty, we still need to do extra check - * against new flags - */ - if (!options) - goto check; - - while ((p = strsep(&options, ",")) != NULL) { - int token; - if (!*p) - continue; - - token = match_token(p, tokens, args); - switch (token) { - case Opt_degraded: - btrfs_info(info, "allowing degraded mounts"); - btrfs_set_opt(info->mount_opt, DEGRADED); - break; - case Opt_subvol: - case Opt_subvol_empty: - case Opt_subvolid: - case Opt_device: - /* - * These are parsed by btrfs_parse_subvol_options or - * btrfs_parse_device_options and can be ignored here. - */ - break; - case Opt_nodatasum: - btrfs_set_and_info(info, NODATASUM, - "setting nodatasum"); - break; - case Opt_datasum: - if (btrfs_test_opt(info, NODATASUM)) { - if (btrfs_test_opt(info, NODATACOW)) - btrfs_info(info, - "setting datasum, datacow enabled"); - else - btrfs_info(info, "setting datasum"); - } - btrfs_clear_opt(info->mount_opt, NODATACOW); - btrfs_clear_opt(info->mount_opt, NODATASUM); - break; - case Opt_nodatacow: - if (!btrfs_test_opt(info, NODATACOW)) { - if (!btrfs_test_opt(info, COMPRESS) || - !btrfs_test_opt(info, FORCE_COMPRESS)) { - btrfs_info(info, - "setting nodatacow, compression disabled"); - } else { - btrfs_info(info, "setting nodatacow"); - } - } - btrfs_clear_opt(info->mount_opt, COMPRESS); - btrfs_clear_opt(info->mount_opt, FORCE_COMPRESS); - btrfs_set_opt(info->mount_opt, NODATACOW); - btrfs_set_opt(info->mount_opt, NODATASUM); - break; - case Opt_datacow: - btrfs_clear_and_info(info, NODATACOW, - "setting datacow"); - break; - case Opt_compress_force: - case Opt_compress_force_type: - compress_force = true; - fallthrough; - case Opt_compress: - case Opt_compress_type: - saved_compress_type = btrfs_test_opt(info, - COMPRESS) ? - info->compress_type : BTRFS_COMPRESS_NONE; - saved_compress_force = - btrfs_test_opt(info, FORCE_COMPRESS); - saved_compress_level = info->compress_level; - if (token == Opt_compress || - token == Opt_compress_force || - strncmp(args[0].from, "zlib", 4) == 0) { - compress_type = "zlib"; - - info->compress_type = BTRFS_COMPRESS_ZLIB; - info->compress_level = BTRFS_ZLIB_DEFAULT_LEVEL; - /* - * args[0] contains uninitialized data since - * for these tokens we don't expect any - * parameter. - */ - if (token != Opt_compress && - token != Opt_compress_force) - info->compress_level = - btrfs_compress_str2level( - BTRFS_COMPRESS_ZLIB, - args[0].from + 4); - btrfs_set_opt(info->mount_opt, COMPRESS); - btrfs_clear_opt(info->mount_opt, NODATACOW); - btrfs_clear_opt(info->mount_opt, NODATASUM); - no_compress = 0; - } else if (strncmp(args[0].from, "lzo", 3) == 0) { - compress_type = "lzo"; - info->compress_type = BTRFS_COMPRESS_LZO; - info->compress_level = 0; - btrfs_set_opt(info->mount_opt, COMPRESS); - btrfs_clear_opt(info->mount_opt, NODATACOW); - btrfs_clear_opt(info->mount_opt, NODATASUM); - btrfs_set_fs_incompat(info, COMPRESS_LZO); - no_compress = 0; - } else if (strncmp(args[0].from, "zstd", 4) == 0) { - compress_type = "zstd"; - info->compress_type = BTRFS_COMPRESS_ZSTD; - info->compress_level = - btrfs_compress_str2level( - BTRFS_COMPRESS_ZSTD, - args[0].from + 4); - btrfs_set_opt(info->mount_opt, COMPRESS); - btrfs_clear_opt(info->mount_opt, NODATACOW); - btrfs_clear_opt(info->mount_opt, NODATASUM); - btrfs_set_fs_incompat(info, COMPRESS_ZSTD); - no_compress = 0; - } else if (strncmp(args[0].from, "no", 2) == 0) { - compress_type = "no"; - info->compress_level = 0; - info->compress_type = 0; - btrfs_clear_opt(info->mount_opt, COMPRESS); - btrfs_clear_opt(info->mount_opt, FORCE_COMPRESS); - compress_force = false; - no_compress++; - } else { - btrfs_err(info, "unrecognized compression value %s", - args[0].from); - ret = -EINVAL; - goto out; - } - - if (compress_force) { - btrfs_set_opt(info->mount_opt, FORCE_COMPRESS); - } else { - /* - * If we remount from compress-force=xxx to - * compress=xxx, we need clear FORCE_COMPRESS - * flag, otherwise, there is no way for users - * to disable forcible compression separately. - */ - btrfs_clear_opt(info->mount_opt, FORCE_COMPRESS); - } - if (no_compress == 1) { - btrfs_info(info, "use no compression"); - } else if ((info->compress_type != saved_compress_type) || - (compress_force != saved_compress_force) || - (info->compress_level != saved_compress_level)) { - btrfs_info(info, "%s %s compression, level %d", - (compress_force) ? "force" : "use", - compress_type, info->compress_level); - } - compress_force = false; - break; - case Opt_ssd: - btrfs_set_and_info(info, SSD, - "enabling ssd optimizations"); - btrfs_clear_opt(info->mount_opt, NOSSD); - break; - case Opt_ssd_spread: - btrfs_set_and_info(info, SSD, - "enabling ssd optimizations"); - btrfs_set_and_info(info, SSD_SPREAD, - "using spread ssd allocation scheme"); - btrfs_clear_opt(info->mount_opt, NOSSD); - break; - case Opt_nossd: - btrfs_set_opt(info->mount_opt, NOSSD); - btrfs_clear_and_info(info, SSD, - "not using ssd optimizations"); - fallthrough; - case Opt_nossd_spread: - btrfs_clear_and_info(info, SSD_SPREAD, - "not using spread ssd allocation scheme"); - break; - case Opt_barrier: - btrfs_clear_and_info(info, NOBARRIER, - "turning on barriers"); - break; - case Opt_nobarrier: - btrfs_set_and_info(info, NOBARRIER, - "turning off barriers"); - break; - case Opt_thread_pool: - ret = match_int(&args[0], &intarg); - if (ret) { - btrfs_err(info, "unrecognized thread_pool value %s", - args[0].from); - goto out; - } else if (intarg == 0) { - btrfs_err(info, "invalid value 0 for thread_pool"); - ret = -EINVAL; - goto out; - } - info->thread_pool_size = intarg; - break; - case Opt_max_inline: - num = match_strdup(&args[0]); - if (num) { - info->max_inline = memparse(num, NULL); - kfree(num); - - if (info->max_inline) { - info->max_inline = min_t(u64, - info->max_inline, - info->sectorsize); - } - btrfs_info(info, "max_inline at %llu", - info->max_inline); - } else { - ret = -ENOMEM; - goto out; - } - break; - case Opt_acl: -#ifdef CONFIG_BTRFS_FS_POSIX_ACL - info->sb->s_flags |= SB_POSIXACL; - break; -#else - btrfs_err(info, "support for ACL not compiled in!"); - ret = -EINVAL; - goto out; -#endif - case Opt_noacl: - info->sb->s_flags &= ~SB_POSIXACL; - break; - case Opt_notreelog: - btrfs_set_and_info(info, NOTREELOG, - "disabling tree log"); - break; - case Opt_treelog: - btrfs_clear_and_info(info, NOTREELOG, - "enabling tree log"); - break; - case Opt_norecovery: - case Opt_nologreplay: - btrfs_warn(info, - "'nologreplay' is deprecated, use 'rescue=nologreplay' instead"); - btrfs_set_and_info(info, NOLOGREPLAY, - "disabling log replay at mount time"); - break; - case Opt_flushoncommit: - btrfs_set_and_info(info, FLUSHONCOMMIT, - "turning on flush-on-commit"); - break; - case Opt_noflushoncommit: - btrfs_clear_and_info(info, FLUSHONCOMMIT, - "turning off flush-on-commit"); - break; - case Opt_ratio: - ret = match_int(&args[0], &intarg); - if (ret) { - btrfs_err(info, "unrecognized metadata_ratio value %s", - args[0].from); - goto out; - } - info->metadata_ratio = intarg; - btrfs_info(info, "metadata ratio %u", - info->metadata_ratio); - break; - case Opt_discard: - case Opt_discard_mode: - if (token == Opt_discard || - strcmp(args[0].from, "sync") == 0) { - btrfs_clear_opt(info->mount_opt, DISCARD_ASYNC); - btrfs_set_and_info(info, DISCARD_SYNC, - "turning on sync discard"); - } else if (strcmp(args[0].from, "async") == 0) { - btrfs_clear_opt(info->mount_opt, DISCARD_SYNC); - btrfs_set_and_info(info, DISCARD_ASYNC, - "turning on async discard"); - } else { - btrfs_err(info, "unrecognized discard mode value %s", - args[0].from); - ret = -EINVAL; - goto out; - } - btrfs_clear_opt(info->mount_opt, NODISCARD); - break; - case Opt_nodiscard: - btrfs_clear_and_info(info, DISCARD_SYNC, - "turning off discard"); - btrfs_clear_and_info(info, DISCARD_ASYNC, - "turning off async discard"); - btrfs_set_opt(info->mount_opt, NODISCARD); - break; - case Opt_space_cache: - case Opt_space_cache_version: - /* - * We already set FREE_SPACE_TREE above because we have - * compat_ro(FREE_SPACE_TREE) set, and we aren't going - * to allow v1 to be set for extent tree v2, simply - * ignore this setting if we're extent tree v2. - */ - if (btrfs_fs_incompat(info, EXTENT_TREE_V2)) - break; - if (token == Opt_space_cache || - strcmp(args[0].from, "v1") == 0) { - btrfs_clear_opt(info->mount_opt, - FREE_SPACE_TREE); - btrfs_set_and_info(info, SPACE_CACHE, - "enabling disk space caching"); - } else if (strcmp(args[0].from, "v2") == 0) { - btrfs_clear_opt(info->mount_opt, - SPACE_CACHE); - btrfs_set_and_info(info, FREE_SPACE_TREE, - "enabling free space tree"); - } else { - btrfs_err(info, "unrecognized space_cache value %s", - args[0].from); - ret = -EINVAL; - goto out; - } - break; - case Opt_rescan_uuid_tree: - btrfs_set_opt(info->mount_opt, RESCAN_UUID_TREE); - break; - case Opt_no_space_cache: - /* - * We cannot operate without the free space tree with - * extent tree v2, ignore this option. - */ - if (btrfs_fs_incompat(info, EXTENT_TREE_V2)) - break; - if (btrfs_test_opt(info, SPACE_CACHE)) { - btrfs_clear_and_info(info, SPACE_CACHE, - "disabling disk space caching"); - } - if (btrfs_test_opt(info, FREE_SPACE_TREE)) { - btrfs_clear_and_info(info, FREE_SPACE_TREE, - "disabling free space tree"); - } - break; - case Opt_inode_cache: - case Opt_noinode_cache: - btrfs_warn(info, - "the 'inode_cache' option is deprecated and has no effect since 5.11"); - break; - case Opt_clear_cache: - /* - * We cannot clear the free space tree with extent tree - * v2, ignore this option. - */ - if (btrfs_fs_incompat(info, EXTENT_TREE_V2)) - break; - btrfs_set_and_info(info, CLEAR_CACHE, - "force clearing of disk cache"); - break; - case Opt_user_subvol_rm_allowed: - btrfs_set_opt(info->mount_opt, USER_SUBVOL_RM_ALLOWED); - break; - case Opt_enospc_debug: - btrfs_set_opt(info->mount_opt, ENOSPC_DEBUG); - break; - case Opt_noenospc_debug: - btrfs_clear_opt(info->mount_opt, ENOSPC_DEBUG); - break; - case Opt_defrag: - btrfs_set_and_info(info, AUTO_DEFRAG, - "enabling auto defrag"); - break; - case Opt_nodefrag: - btrfs_clear_and_info(info, AUTO_DEFRAG, - "disabling auto defrag"); - break; - case Opt_recovery: - case Opt_usebackuproot: - btrfs_warn(info, - "'%s' is deprecated, use 'rescue=usebackuproot' instead", - token == Opt_recovery ? "recovery" : - "usebackuproot"); - btrfs_info(info, - "trying to use backup root at mount time"); - btrfs_set_opt(info->mount_opt, USEBACKUPROOT); - break; - case Opt_skip_balance: - btrfs_set_opt(info->mount_opt, SKIP_BALANCE); - break; -#ifdef CONFIG_BTRFS_FS_CHECK_INTEGRITY - case Opt_check_integrity_including_extent_data: - btrfs_info(info, - "enabling check integrity including extent data"); - btrfs_set_opt(info->mount_opt, CHECK_INTEGRITY_DATA); - btrfs_set_opt(info->mount_opt, CHECK_INTEGRITY); - break; - case Opt_check_integrity: - btrfs_info(info, "enabling check integrity"); - btrfs_set_opt(info->mount_opt, CHECK_INTEGRITY); - break; - case Opt_check_integrity_print_mask: - ret = match_int(&args[0], &intarg); - if (ret) { - btrfs_err(info, - "unrecognized check_integrity_print_mask value %s", - args[0].from); - goto out; - } - info->check_integrity_print_mask = intarg; - btrfs_info(info, "check_integrity_print_mask 0x%x", - info->check_integrity_print_mask); - break; -#else - case Opt_check_integrity_including_extent_data: - case Opt_check_integrity: - case Opt_check_integrity_print_mask: - btrfs_err(info, - "support for check_integrity* not compiled in!"); - ret = -EINVAL; - goto out; -#endif - case Opt_fatal_errors: - if (strcmp(args[0].from, "panic") == 0) { - btrfs_set_opt(info->mount_opt, - PANIC_ON_FATAL_ERROR); - } else if (strcmp(args[0].from, "bug") == 0) { - btrfs_clear_opt(info->mount_opt, - PANIC_ON_FATAL_ERROR); - } else { - btrfs_err(info, "unrecognized fatal_errors value %s", - args[0].from); - ret = -EINVAL; - goto out; - } - break; - case Opt_commit_interval: - intarg = 0; - ret = match_int(&args[0], &intarg); - if (ret) { - btrfs_err(info, "unrecognized commit_interval value %s", - args[0].from); - ret = -EINVAL; - goto out; - } - if (intarg == 0) { - btrfs_info(info, - "using default commit interval %us", - BTRFS_DEFAULT_COMMIT_INTERVAL); - intarg = BTRFS_DEFAULT_COMMIT_INTERVAL; - } else if (intarg > 300) { - btrfs_warn(info, "excessive commit interval %d", - intarg); - } - info->commit_interval = intarg; - break; - case Opt_rescue: - ret = parse_rescue_options(info, args[0].from); - if (ret < 0) { - btrfs_err(info, "unrecognized rescue value %s", - args[0].from); - goto out; - } - break; -#ifdef CONFIG_BTRFS_DEBUG - case Opt_fragment_all: - btrfs_info(info, "fragmenting all space"); - btrfs_set_opt(info->mount_opt, FRAGMENT_DATA); - btrfs_set_opt(info->mount_opt, FRAGMENT_METADATA); - break; - case Opt_fragment_metadata: - btrfs_info(info, "fragmenting metadata"); - btrfs_set_opt(info->mount_opt, - FRAGMENT_METADATA); - break; - case Opt_fragment_data: - btrfs_info(info, "fragmenting data"); - btrfs_set_opt(info->mount_opt, FRAGMENT_DATA); - break; -#endif -#ifdef CONFIG_BTRFS_FS_REF_VERIFY - case Opt_ref_verify: - btrfs_info(info, "doing ref verification"); - btrfs_set_opt(info->mount_opt, REF_VERIFY); - break; -#endif - case Opt_err: - btrfs_err(info, "unrecognized mount option '%s'", p); - ret = -EINVAL; - goto out; - default: - break; - } - } -check: - /* We're read-only, don't have to check. */ - if (new_flags & SB_RDONLY) - goto out; - - if (check_ro_option(info, BTRFS_MOUNT_NOLOGREPLAY, "nologreplay") || - check_ro_option(info, BTRFS_MOUNT_IGNOREBADROOTS, "ignorebadroots") || - check_ro_option(info, BTRFS_MOUNT_IGNOREDATACSUMS, "ignoredatacsums")) - ret = -EINVAL; -out: - if (btrfs_fs_compat_ro(info, FREE_SPACE_TREE) && - !btrfs_test_opt(info, FREE_SPACE_TREE) && - !btrfs_test_opt(info, CLEAR_CACHE)) { - btrfs_err(info, "cannot disable free space tree"); - ret = -EINVAL; - } - if (btrfs_fs_compat_ro(info, BLOCK_GROUP_TREE) && - !btrfs_test_opt(info, FREE_SPACE_TREE)) { - btrfs_err(info, "cannot disable free space tree with block-group-tree feature"); - ret = -EINVAL; - } - if (!ret) - ret = btrfs_check_mountopts_zoned(info); - if (!ret && !remounting) { - if (btrfs_test_opt(info, SPACE_CACHE)) - btrfs_info(info, "disk space caching is enabled"); - if (btrfs_test_opt(info, FREE_SPACE_TREE)) - btrfs_info(info, "using free space tree"); - } - return ret; -} - -/* - * Parse mount options that are required early in the mount process. - * - * All other options will be parsed on much later in the mount process and - * only when we need to allocate a new super block. - */ -static int btrfs_parse_device_options(const char *options, blk_mode_t flags) -{ - substring_t args[MAX_OPT_ARGS]; - char *device_name, *opts, *orig, *p; - struct btrfs_device *device = NULL; - int error = 0; - - lockdep_assert_held(&uuid_mutex); - - if (!options) - return 0; - - /* - * strsep changes the string, duplicate it because btrfs_parse_options - * gets called later - */ - opts = kstrdup(options, GFP_KERNEL); - if (!opts) - return -ENOMEM; - orig = opts; - - while ((p = strsep(&opts, ",")) != NULL) { - int token; - - if (!*p) - continue; - - token = match_token(p, tokens, args); - if (token == Opt_device) { - device_name = match_strdup(&args[0]); - if (!device_name) { - error = -ENOMEM; - goto out; - } - device = btrfs_scan_one_device(device_name, flags); - kfree(device_name); - if (IS_ERR(device)) { - error = PTR_ERR(device); - goto out; - } - } - } - -out: - kfree(orig); - return error; -} - -/* - * Parse mount options that are related to subvolume id - * - * The value is later passed to mount_subvol() - */ -static int btrfs_parse_subvol_options(const char *options, char **subvol_name, - u64 *subvol_objectid) -{ - substring_t args[MAX_OPT_ARGS]; - char *opts, *orig, *p; - int error = 0; - u64 subvolid; - - if (!options) - return 0; - - /* - * strsep changes the string, duplicate it because - * btrfs_parse_device_options gets called later - */ - opts = kstrdup(options, GFP_KERNEL); - if (!opts) - return -ENOMEM; - orig = opts; - - while ((p = strsep(&opts, ",")) != NULL) { - int token; - if (!*p) - continue; - - token = match_token(p, tokens, args); - switch (token) { - case Opt_subvol: - kfree(*subvol_name); - *subvol_name = match_strdup(&args[0]); - if (!*subvol_name) { - error = -ENOMEM; - goto out; - } - break; - case Opt_subvolid: - error = match_u64(&args[0], &subvolid); - if (error) - goto out; - - /* we want the original fs_tree */ - if (subvolid == 0) - subvolid = BTRFS_FS_TREE_OBJECTID; - - *subvol_objectid = subvolid; - break; - default: - break; - } - } - -out: - kfree(orig); - return error; -} - char *btrfs_get_subvol_name_from_objectid(struct btrfs_fs_info *fs_info, u64 subvol_objectid) { @@ -1080,50 +192,8 @@ char *btrfs_get_subvol_name_from_objectid(struct btrfs_fs_info *fs_info, return ERR_PTR(ret); } -static int get_default_subvol_objectid(struct btrfs_fs_info *fs_info, u64 *objectid) -{ - struct btrfs_root *root = fs_info->tree_root; - struct btrfs_dir_item *di; - struct btrfs_path *path; - struct btrfs_key location; - struct fscrypt_str name = FSTR_INIT("default", 7); - u64 dir_id; - - path = btrfs_alloc_path(); - if (!path) - return -ENOMEM; - - /* - * Find the "default" dir item which points to the root item that we - * will mount by default if we haven't been given a specific subvolume - * to mount. - */ - dir_id = btrfs_super_root_dir(fs_info->super_copy); - di = btrfs_lookup_dir_item(NULL, root, path, dir_id, &name, 0); - if (IS_ERR(di)) { - btrfs_free_path(path); - return PTR_ERR(di); - } - if (!di) { - /* - * Ok the default dir item isn't there. This is weird since - * it's always been there, but don't freak out, just try and - * mount the top-level subvolume. - */ - btrfs_free_path(path); - *objectid = BTRFS_FS_TREE_OBJECTID; - return 0; - } - - btrfs_dir_item_key_to_cpu(path->nodes[0], di, &location); - btrfs_free_path(path); - *objectid = location.objectid; - return 0; -} - -static int btrfs_fill_super(struct super_block *sb, - struct btrfs_fs_devices *fs_devices, - void *data) +int btrfs_fill_super(struct fs_context *fc, struct super_block *sb, + struct btrfs_fs_devices *fs_devices) { struct inode *inode; struct btrfs_fs_info *fs_info = btrfs_sb(sb); @@ -1139,10 +209,6 @@ static int btrfs_fill_super(struct super_block *sb, #endif sb->s_xattr = btrfs_xattr_handlers; sb->s_time_gran = 1; -#ifdef CONFIG_BTRFS_FS_POSIX_ACL - sb->s_flags |= SB_POSIXACL; -#endif - sb->s_flags |= SB_I_VERSION; sb->s_iflags |= SB_I_CGROUPWB; err = super_setup_bdi(sb); @@ -1151,7 +217,7 @@ static int btrfs_fill_super(struct super_block *sb, return err; } - err = open_ctree(sb, fs_devices, (char *)data); + err = open_ctree(fc, sb, fs_devices); if (err) { btrfs_err(fs_info, "open_ctree failed"); return err; @@ -1334,542 +400,6 @@ static int btrfs_show_options(struct seq_file *seq, struct dentry *dentry) return 0; } -static int btrfs_test_super(struct super_block *s, void *data) -{ - struct btrfs_fs_info *p = data; - struct btrfs_fs_info *fs_info = btrfs_sb(s); - - return fs_info->fs_devices == p->fs_devices; -} - -static int btrfs_set_super(struct super_block *s, void *data) -{ - int err = set_anon_super(s, data); - if (!err) - s->s_fs_info = data; - return err; -} - -/* - * subvolumes are identified by ino 256 - */ -static inline int is_subvolume_inode(struct inode *inode) -{ - if (inode && inode->i_ino == BTRFS_FIRST_FREE_OBJECTID) - return 1; - return 0; -} - -static struct dentry *mount_subvol(const char *subvol_name, u64 subvol_objectid, - struct vfsmount *mnt) -{ - struct dentry *root; - int ret; - - if (!subvol_name) { - if (!subvol_objectid) { - ret = get_default_subvol_objectid(btrfs_sb(mnt->mnt_sb), - &subvol_objectid); - if (ret) { - root = ERR_PTR(ret); - goto out; - } - } - subvol_name = btrfs_get_subvol_name_from_objectid( - btrfs_sb(mnt->mnt_sb), subvol_objectid); - if (IS_ERR(subvol_name)) { - root = ERR_CAST(subvol_name); - subvol_name = NULL; - goto out; - } - - } - - root = mount_subtree(mnt, subvol_name); - /* mount_subtree() drops our reference on the vfsmount. */ - mnt = NULL; - - if (!IS_ERR(root)) { - struct super_block *s = root->d_sb; - struct btrfs_fs_info *fs_info = btrfs_sb(s); - struct inode *root_inode = d_inode(root); - u64 root_objectid = BTRFS_I(root_inode)->root->root_key.objectid; - - ret = 0; - if (!is_subvolume_inode(root_inode)) { - btrfs_err(fs_info, "'%s' is not a valid subvolume", - subvol_name); - ret = -EINVAL; - } - if (subvol_objectid && root_objectid != subvol_objectid) { - /* - * This will also catch a race condition where a - * subvolume which was passed by ID is renamed and - * another subvolume is renamed over the old location. - */ - btrfs_err(fs_info, - "subvol '%s' does not match subvolid %llu", - subvol_name, subvol_objectid); - ret = -EINVAL; - } - if (ret) { - dput(root); - root = ERR_PTR(ret); - deactivate_locked_super(s); - } - } - -out: - mntput(mnt); - kfree(subvol_name); - return root; -} - -/* - * Find a superblock for the given device / mount point. - * - * Note: This is based on mount_bdev from fs/super.c with a few additions - * for multiple device setup. Make sure to keep it in sync. - */ -static struct dentry *btrfs_mount_root(struct file_system_type *fs_type, - int flags, const char *device_name, void *data) -{ - struct block_device *bdev = NULL; - struct super_block *s; - struct btrfs_device *device = NULL; - struct btrfs_fs_devices *fs_devices = NULL; - struct btrfs_fs_info *fs_info = NULL; - void *new_sec_opts = NULL; - blk_mode_t mode = sb_open_mode(flags); - int error = 0; - - if (data) { - error = security_sb_eat_lsm_opts(data, &new_sec_opts); - if (error) - return ERR_PTR(error); - } - - /* - * Setup a dummy root and fs_info for test/set super. This is because - * we don't actually fill this stuff out until open_ctree, but we need - * then open_ctree will properly initialize the file system specific - * settings later. btrfs_init_fs_info initializes the static elements - * of the fs_info (locks and such) to make cleanup easier if we find a - * superblock with our given fs_devices later on at sget() time. - */ - fs_info = kvzalloc(sizeof(struct btrfs_fs_info), GFP_KERNEL); - if (!fs_info) { - error = -ENOMEM; - goto error_sec_opts; - } - btrfs_init_fs_info(fs_info); - - fs_info->super_copy = kzalloc(BTRFS_SUPER_INFO_SIZE, GFP_KERNEL); - fs_info->super_for_commit = kzalloc(BTRFS_SUPER_INFO_SIZE, GFP_KERNEL); - if (!fs_info->super_copy || !fs_info->super_for_commit) { - error = -ENOMEM; - goto error_fs_info; - } - - mutex_lock(&uuid_mutex); - error = btrfs_parse_device_options(data, mode); - if (error) { - mutex_unlock(&uuid_mutex); - goto error_fs_info; - } - - device = btrfs_scan_one_device(device_name, mode); - if (IS_ERR(device)) { - mutex_unlock(&uuid_mutex); - error = PTR_ERR(device); - goto error_fs_info; - } - - fs_devices = device->fs_devices; - fs_info->fs_devices = fs_devices; - - error = btrfs_open_devices(fs_devices, mode, fs_type); - mutex_unlock(&uuid_mutex); - if (error) - goto error_fs_info; - - if (!(flags & SB_RDONLY) && fs_devices->rw_devices == 0) { - error = -EACCES; - goto error_close_devices; - } - - bdev = fs_devices->latest_dev->bdev; - s = sget(fs_type, btrfs_test_super, btrfs_set_super, flags | SB_NOSEC, - fs_info); - if (IS_ERR(s)) { - error = PTR_ERR(s); - goto error_close_devices; - } - - if (s->s_root) { - btrfs_close_devices(fs_devices); - btrfs_free_fs_info(fs_info); - if ((flags ^ s->s_flags) & SB_RDONLY) - error = -EBUSY; - } else { - snprintf(s->s_id, sizeof(s->s_id), "%pg", bdev); - shrinker_debugfs_rename(&s->s_shrink, "sb-%s:%s", fs_type->name, - s->s_id); - btrfs_sb(s)->bdev_holder = fs_type; - error = btrfs_fill_super(s, fs_devices, data); - } - if (!error) - error = security_sb_set_mnt_opts(s, new_sec_opts, 0, NULL); - security_free_mnt_opts(&new_sec_opts); - if (error) { - deactivate_locked_super(s); - return ERR_PTR(error); - } - - return dget(s->s_root); - -error_close_devices: - btrfs_close_devices(fs_devices); -error_fs_info: - btrfs_free_fs_info(fs_info); -error_sec_opts: - security_free_mnt_opts(&new_sec_opts); - return ERR_PTR(error); -} - -/* - * Mount function which is called by VFS layer. - * - * In order to allow mounting a subvolume directly, btrfs uses mount_subtree() - * which needs vfsmount* of device's root (/). This means device's root has to - * be mounted internally in any case. - * - * Operation flow: - * 1. Parse subvol id related options for later use in mount_subvol(). - * - * 2. Mount device's root (/) by calling vfs_kern_mount(). - * - * NOTE: vfs_kern_mount() is used by VFS to call btrfs_mount() in the - * first place. In order to avoid calling btrfs_mount() again, we use - * different file_system_type which is not registered to VFS by - * register_filesystem() (btrfs_root_fs_type). As a result, - * btrfs_mount_root() is called. The return value will be used by - * mount_subtree() in mount_subvol(). - * - * 3. Call mount_subvol() to get the dentry of subvolume. Since there is - * "btrfs subvolume set-default", mount_subvol() is called always. - */ -static struct dentry *btrfs_mount(struct file_system_type *fs_type, int flags, - const char *device_name, void *data) -{ - struct vfsmount *mnt_root; - struct dentry *root; - char *subvol_name = NULL; - u64 subvol_objectid = 0; - int error = 0; - - error = btrfs_parse_subvol_options(data, &subvol_name, - &subvol_objectid); - if (error) { - kfree(subvol_name); - return ERR_PTR(error); - } - - /* mount device's root (/) */ - mnt_root = vfs_kern_mount(&btrfs_root_fs_type, flags, device_name, data); - if (PTR_ERR_OR_ZERO(mnt_root) == -EBUSY) { - if (flags & SB_RDONLY) { - mnt_root = vfs_kern_mount(&btrfs_root_fs_type, - flags & ~SB_RDONLY, device_name, data); - } else { - mnt_root = vfs_kern_mount(&btrfs_root_fs_type, - flags | SB_RDONLY, device_name, data); - if (IS_ERR(mnt_root)) { - root = ERR_CAST(mnt_root); - kfree(subvol_name); - goto out; - } - - down_write(&mnt_root->mnt_sb->s_umount); - error = btrfs_remount(mnt_root->mnt_sb, &flags, NULL); - up_write(&mnt_root->mnt_sb->s_umount); - if (error < 0) { - root = ERR_PTR(error); - mntput(mnt_root); - kfree(subvol_name); - goto out; - } - } - } - if (IS_ERR(mnt_root)) { - root = ERR_CAST(mnt_root); - kfree(subvol_name); - goto out; - } - - /* mount_subvol() will free subvol_name and mnt_root */ - root = mount_subvol(subvol_name, subvol_objectid, mnt_root); - -out: - return root; -} - -static void btrfs_resize_thread_pool(struct btrfs_fs_info *fs_info, - u32 new_pool_size, u32 old_pool_size) -{ - if (new_pool_size == old_pool_size) - return; - - fs_info->thread_pool_size = new_pool_size; - - btrfs_info(fs_info, "resize thread pool %d -> %d", - old_pool_size, new_pool_size); - - btrfs_workqueue_set_max(fs_info->workers, new_pool_size); - btrfs_workqueue_set_max(fs_info->hipri_workers, new_pool_size); - btrfs_workqueue_set_max(fs_info->delalloc_workers, new_pool_size); - btrfs_workqueue_set_max(fs_info->caching_workers, new_pool_size); - workqueue_set_max_active(fs_info->endio_workers, new_pool_size); - workqueue_set_max_active(fs_info->endio_meta_workers, new_pool_size); - btrfs_workqueue_set_max(fs_info->endio_write_workers, new_pool_size); - btrfs_workqueue_set_max(fs_info->endio_freespace_worker, new_pool_size); - btrfs_workqueue_set_max(fs_info->delayed_workers, new_pool_size); -} - -static inline void btrfs_remount_begin(struct btrfs_fs_info *fs_info, - unsigned long old_opts, int flags) -{ - if (btrfs_raw_test_opt(old_opts, AUTO_DEFRAG) && - (!btrfs_raw_test_opt(fs_info->mount_opt, AUTO_DEFRAG) || - (flags & SB_RDONLY))) { - /* wait for any defraggers to finish */ - wait_event(fs_info->transaction_wait, - (atomic_read(&fs_info->defrag_running) == 0)); - if (flags & SB_RDONLY) - sync_filesystem(fs_info->sb); - } -} - -static inline void btrfs_remount_cleanup(struct btrfs_fs_info *fs_info, - unsigned long old_opts) -{ - const bool cache_opt = btrfs_test_opt(fs_info, SPACE_CACHE); - - /* - * We need to cleanup all defragable inodes if the autodefragment is - * close or the filesystem is read only. - */ - if (btrfs_raw_test_opt(old_opts, AUTO_DEFRAG) && - (!btrfs_raw_test_opt(fs_info->mount_opt, AUTO_DEFRAG) || sb_rdonly(fs_info->sb))) { - btrfs_cleanup_defrag_inodes(fs_info); - } - - /* If we toggled discard async */ - if (!btrfs_raw_test_opt(old_opts, DISCARD_ASYNC) && - btrfs_test_opt(fs_info, DISCARD_ASYNC)) - btrfs_discard_resume(fs_info); - else if (btrfs_raw_test_opt(old_opts, DISCARD_ASYNC) && - !btrfs_test_opt(fs_info, DISCARD_ASYNC)) - btrfs_discard_cleanup(fs_info); - - /* If we toggled space cache */ - if (cache_opt != btrfs_free_space_cache_v1_active(fs_info)) - btrfs_set_free_space_cache_v1_active(fs_info, cache_opt); -} - -static int btrfs_remount(struct super_block *sb, int *flags, char *data) -{ - struct btrfs_fs_info *fs_info = btrfs_sb(sb); - unsigned old_flags = sb->s_flags; - unsigned long old_opts = fs_info->mount_opt; - unsigned long old_compress_type = fs_info->compress_type; - u64 old_max_inline = fs_info->max_inline; - u32 old_thread_pool_size = fs_info->thread_pool_size; - u32 old_metadata_ratio = fs_info->metadata_ratio; - int ret; - - sync_filesystem(sb); - set_bit(BTRFS_FS_STATE_REMOUNTING, &fs_info->fs_state); - - if (data) { - void *new_sec_opts = NULL; - - ret = security_sb_eat_lsm_opts(data, &new_sec_opts); - if (!ret) - ret = security_sb_remount(sb, new_sec_opts); - security_free_mnt_opts(&new_sec_opts); - if (ret) - goto restore; - } - - ret = btrfs_parse_options(fs_info, data, *flags); - if (ret) - goto restore; - - ret = btrfs_check_features(fs_info, !(*flags & SB_RDONLY)); - if (ret < 0) - goto restore; - - btrfs_remount_begin(fs_info, old_opts, *flags); - btrfs_resize_thread_pool(fs_info, - fs_info->thread_pool_size, old_thread_pool_size); - - if ((bool)btrfs_test_opt(fs_info, FREE_SPACE_TREE) != - (bool)btrfs_fs_compat_ro(fs_info, FREE_SPACE_TREE) && - (!sb_rdonly(sb) || (*flags & SB_RDONLY))) { - btrfs_warn(fs_info, - "remount supports changing free space tree only from ro to rw"); - /* Make sure free space cache options match the state on disk */ - if (btrfs_fs_compat_ro(fs_info, FREE_SPACE_TREE)) { - btrfs_set_opt(fs_info->mount_opt, FREE_SPACE_TREE); - btrfs_clear_opt(fs_info->mount_opt, SPACE_CACHE); - } - if (btrfs_free_space_cache_v1_active(fs_info)) { - btrfs_clear_opt(fs_info->mount_opt, FREE_SPACE_TREE); - btrfs_set_opt(fs_info->mount_opt, SPACE_CACHE); - } - } - - if ((bool)(*flags & SB_RDONLY) == sb_rdonly(sb)) - goto out; - - if (*flags & SB_RDONLY) { - /* - * this also happens on 'umount -rf' or on shutdown, when - * the filesystem is busy. - */ - cancel_work_sync(&fs_info->async_reclaim_work); - cancel_work_sync(&fs_info->async_data_reclaim_work); - - btrfs_discard_cleanup(fs_info); - - /* wait for the uuid_scan task to finish */ - down(&fs_info->uuid_tree_rescan_sem); - /* avoid complains from lockdep et al. */ - up(&fs_info->uuid_tree_rescan_sem); - - btrfs_set_sb_rdonly(sb); - - /* - * Setting SB_RDONLY will put the cleaner thread to - * sleep at the next loop if it's already active. - * If it's already asleep, we'll leave unused block - * groups on disk until we're mounted read-write again - * unless we clean them up here. - */ - btrfs_delete_unused_bgs(fs_info); - - /* - * The cleaner task could be already running before we set the - * flag BTRFS_FS_STATE_RO (and SB_RDONLY in the superblock). - * We must make sure that after we finish the remount, i.e. after - * we call btrfs_commit_super(), the cleaner can no longer start - * a transaction - either because it was dropping a dead root, - * running delayed iputs or deleting an unused block group (the - * cleaner picked a block group from the list of unused block - * groups before we were able to in the previous call to - * btrfs_delete_unused_bgs()). - */ - wait_on_bit(&fs_info->flags, BTRFS_FS_CLEANER_RUNNING, - TASK_UNINTERRUPTIBLE); - - /* - * We've set the superblock to RO mode, so we might have made - * the cleaner task sleep without running all pending delayed - * iputs. Go through all the delayed iputs here, so that if an - * unmount happens without remounting RW we don't end up at - * finishing close_ctree() with a non-empty list of delayed - * iputs. - */ - btrfs_run_delayed_iputs(fs_info); - - btrfs_dev_replace_suspend_for_unmount(fs_info); - btrfs_scrub_cancel(fs_info); - btrfs_pause_balance(fs_info); - - /* - * Pause the qgroup rescan worker if it is running. We don't want - * it to be still running after we are in RO mode, as after that, - * by the time we unmount, it might have left a transaction open, - * so we would leak the transaction and/or crash. - */ - btrfs_qgroup_wait_for_completion(fs_info, false); - - ret = btrfs_commit_super(fs_info); - if (ret) - goto restore; - } else { - if (BTRFS_FS_ERROR(fs_info)) { - btrfs_err(fs_info, - "Remounting read-write after error is not allowed"); - ret = -EINVAL; - goto restore; - } - if (fs_info->fs_devices->rw_devices == 0) { - ret = -EACCES; - goto restore; - } - - if (!btrfs_check_rw_degradable(fs_info, NULL)) { - btrfs_warn(fs_info, - "too many missing devices, writable remount is not allowed"); - ret = -EACCES; - goto restore; - } - - if (btrfs_super_log_root(fs_info->super_copy) != 0) { - btrfs_warn(fs_info, - "mount required to replay tree-log, cannot remount read-write"); - ret = -EINVAL; - goto restore; - } - - /* - * NOTE: when remounting with a change that does writes, don't - * put it anywhere above this point, as we are not sure to be - * safe to write until we pass the above checks. - */ - ret = btrfs_start_pre_rw_mount(fs_info); - if (ret) - goto restore; - - btrfs_clear_sb_rdonly(sb); - - set_bit(BTRFS_FS_OPEN, &fs_info->flags); - } -out: - /* - * We need to set SB_I_VERSION here otherwise it'll get cleared by VFS, - * since the absence of the flag means it can be toggled off by remount. - */ - *flags |= SB_I_VERSION; - - wake_up_process(fs_info->transaction_kthread); - btrfs_remount_cleanup(fs_info, old_opts); - btrfs_clear_oneshot_options(fs_info); - clear_bit(BTRFS_FS_STATE_REMOUNTING, &fs_info->fs_state); - - return 0; - -restore: - /* We've hit an error - don't reset SB_RDONLY */ - if (sb_rdonly(sb)) - old_flags |= SB_RDONLY; - if (!(old_flags & SB_RDONLY)) - clear_bit(BTRFS_FS_STATE_RO, &fs_info->fs_state); - sb->s_flags = old_flags; - fs_info->mount_opt = old_opts; - fs_info->compress_type = old_compress_type; - fs_info->max_inline = old_max_inline; - btrfs_resize_thread_pool(fs_info, - old_thread_pool_size, fs_info->thread_pool_size); - fs_info->metadata_ratio = old_metadata_ratio; - btrfs_remount_cleanup(fs_info, old_opts); - clear_bit(BTRFS_FS_STATE_REMOUNTING, &fs_info->fs_state); - - return ret; -} - /* Used to sort the devices by max_avail(descending sort) */ static int btrfs_cmp_device_free_bytes(const void *a, const void *b) { @@ -2134,20 +664,13 @@ static void btrfs_kill_super(struct super_block *sb) btrfs_free_fs_info(fs_info); } -static struct file_system_type btrfs_fs_type = { - .owner = THIS_MODULE, - .name = "btrfs", - .mount = btrfs_mount, - .kill_sb = btrfs_kill_super, - .fs_flags = FS_REQUIRES_DEV | FS_BINARY_MOUNTDATA, -}; - -static struct file_system_type btrfs_root_fs_type = { - .owner = THIS_MODULE, - .name = "btrfs", - .mount = btrfs_mount_root, - .kill_sb = btrfs_kill_super, - .fs_flags = FS_REQUIRES_DEV | FS_BINARY_MOUNTDATA | FS_ALLOW_IDMAP, +struct file_system_type btrfs_fs_type = { + .owner = THIS_MODULE, + .name = "btrfs", + .init_fs_context = btrfs_init_fs_context, + .parameters = btrfs_parameter_spec, + .kill_sb = btrfs_kill_super, + .fs_flags = FS_REQUIRES_DEV | FS_BINARY_MOUNTDATA | FS_ALLOW_IDMAP, }; MODULE_ALIAS_FS("btrfs"); @@ -2352,7 +875,6 @@ static const struct super_operations btrfs_super_ops = { .destroy_inode = btrfs_destroy_inode, .free_inode = btrfs_free_inode, .statfs = btrfs_statfs, - .remount_fs = btrfs_remount, .freeze_fs = btrfs_freeze, .unfreeze_fs = btrfs_unfreeze, }; diff --git a/fs/btrfs/super.h b/fs/btrfs/super.h index 8dbb909b364f..2901eea1541c 100644 --- a/fs/btrfs/super.h +++ b/fs/btrfs/super.h @@ -3,8 +3,8 @@ #ifndef BTRFS_SUPER_H #define BTRFS_SUPER_H -int btrfs_parse_options(struct btrfs_fs_info *info, char *options, - unsigned long new_flags); +extern struct file_system_type btrfs_fs_type; + int btrfs_sync_fs(struct super_block *sb, int wait); char *btrfs_get_subvol_name_from_objectid(struct btrfs_fs_info *fs_info, u64 subvol_objectid); @@ -26,4 +26,7 @@ static inline void btrfs_clear_sb_rdonly(struct super_block *sb) clear_bit(BTRFS_FS_STATE_RO, &btrfs_sb(sb)->fs_state); } +int btrfs_fill_super(struct fs_context *fc, struct super_block *sb, + struct btrfs_fs_devices *fs_devices); + #endif