From patchwork Thu Feb 16 20:39:10 2023 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: "Darrick J. Wong" X-Patchwork-Id: 13143787 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 650C0C61DA4 for ; Thu, 16 Feb 2023 20:39:21 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S229852AbjBPUjT (ORCPT ); Thu, 16 Feb 2023 15:39:19 -0500 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:53258 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S229783AbjBPUjP (ORCPT ); Thu, 16 Feb 2023 15:39:15 -0500 Received: from dfw.source.kernel.org (dfw.source.kernel.org [IPv6:2604:1380:4641:c500::1]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 06940211DE for ; Thu, 16 Feb 2023 12:39:12 -0800 (PST) Received: from smtp.kernel.org (relay.kernel.org [52.25.139.140]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by dfw.source.kernel.org (Postfix) with ESMTPS id 909D960C1E for ; Thu, 16 Feb 2023 20:39:11 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id ED1FEC4339B; Thu, 16 Feb 2023 20:39:10 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1676579951; bh=uTe3aQuTOHJ8JXrnP1Cusl2wxeDQLNxu1H/cSD3SmMg=; h=Date:Subject:From:To:Cc:In-Reply-To:References:From; b=vFB3w8IhxQ4gMybVdrmbs00euzz0UlUGh5QcI7BKL0dDqkE28vVGFYy+ZqqOa0VAF L0ayWqnh+tgYglhsCnZLr8IqqGSdHGNlz5V9GgRsEIVPm9qGjJnuarmdY2YM9VjKRQ qv5sJ4uDMZvIrYnhDTTPwcUulhszx/hwnCygTDw/96mjnxr5WO1cyqoHesGZzZ+ZAN zwZczyjsPkcLswuO3lAowfid3yayo5hqZiXapVRySEW3RNhSViQDAEWzMBRZjUSjZ5 hF8Awuebfjm/2WAz+IelI33qK0I1i9vuPPP8RygMt1ZyaeZ+n4R5+F32fNU6i7aKBM GPTs/b/iTUgrg== Date: Thu, 16 Feb 2023 12:39:10 -0800 Subject: [PATCH 25/28] xfs: Add parent pointer ioctl From: "Darrick J. Wong" To: djwong@kernel.org Cc: Allison Henderson , allison.henderson@oracle.com, linux-xfs@vger.kernel.org Message-ID: <167657872744.3473407.10713843286901630791.stgit@magnolia> In-Reply-To: <167657872335.3473407.14628732092515467392.stgit@magnolia> References: <167657872335.3473407.14628732092515467392.stgit@magnolia> User-Agent: StGit/0.19 MIME-Version: 1.0 Precedence: bulk List-ID: X-Mailing-List: linux-xfs@vger.kernel.org From: Allison Henderson This patch adds a new file ioctl to retrieve the parent pointer of a given inode Signed-off-by: Allison Henderson --- fs/xfs/Makefile | 1 fs/xfs/libxfs/xfs_fs.h | 74 ++++++++++++++++++++++++++ fs/xfs/libxfs/xfs_parent.c | 10 +++ fs/xfs/libxfs/xfs_parent.h | 2 + fs/xfs/xfs_ioctl.c | 94 ++++++++++++++++++++++++++++++++- fs/xfs/xfs_ondisk.h | 4 + fs/xfs/xfs_parent_utils.c | 126 ++++++++++++++++++++++++++++++++++++++++++++ fs/xfs/xfs_parent_utils.h | 11 ++++ 8 files changed, 321 insertions(+), 1 deletion(-) create mode 100644 fs/xfs/xfs_parent_utils.c create mode 100644 fs/xfs/xfs_parent_utils.h diff --git a/fs/xfs/Makefile b/fs/xfs/Makefile index e2b2cf50ffcf..42d0496fdad7 100644 --- a/fs/xfs/Makefile +++ b/fs/xfs/Makefile @@ -86,6 +86,7 @@ xfs-y += xfs_aops.o \ xfs_mount.o \ xfs_mru_cache.o \ xfs_pwork.o \ + xfs_parent_utils.o \ xfs_reflink.o \ xfs_stats.o \ xfs_super.o \ diff --git a/fs/xfs/libxfs/xfs_fs.h b/fs/xfs/libxfs/xfs_fs.h index b0b4d7a3aa15..9e59a1fdfb0c 100644 --- a/fs/xfs/libxfs/xfs_fs.h +++ b/fs/xfs/libxfs/xfs_fs.h @@ -752,6 +752,79 @@ struct xfs_scrub_metadata { XFS_SCRUB_OFLAG_NO_REPAIR_NEEDED) #define XFS_SCRUB_FLAGS_ALL (XFS_SCRUB_FLAGS_IN | XFS_SCRUB_FLAGS_OUT) +#define XFS_PPTR_MAXNAMELEN 256 + +/* return parents of the handle, not the open fd */ +#define XFS_PPTR_IFLAG_HANDLE (1U << 0) + +/* target was the root directory */ +#define XFS_PPTR_OFLAG_ROOT (1U << 1) + +/* Cursor is done iterating pptrs */ +#define XFS_PPTR_OFLAG_DONE (1U << 2) + + #define XFS_PPTR_FLAG_ALL (XFS_PPTR_IFLAG_HANDLE | XFS_PPTR_OFLAG_ROOT | \ + XFS_PPTR_OFLAG_DONE) + +/* Get an inode parent pointer through ioctl */ +struct xfs_parent_ptr { + __u64 xpp_ino; /* Inode */ + __u32 xpp_gen; /* Inode generation */ + __u32 xpp_diroffset; /* Directory offset */ + __u64 xpp_rsvd; /* Reserved */ + __u8 xpp_name[XFS_PPTR_MAXNAMELEN]; /* File name */ +}; + +/* Iterate through an inodes parent pointers */ +struct xfs_pptr_info { + /* File handle, if XFS_PPTR_IFLAG_HANDLE is set */ + struct xfs_handle pi_handle; + + /* + * Structure to track progress in iterating the parent pointers. + * Must be initialized to zeroes before the first ioctl call, and + * not touched by callers after that. + */ + struct xfs_attrlist_cursor pi_cursor; + + /* Operational flags: XFS_PPTR_*FLAG* */ + __u32 pi_flags; + + /* Must be set to zero */ + __u32 pi_reserved; + + /* # of entries in array */ + __u32 pi_ptrs_size; + + /* # of entries filled in (output) */ + __u32 pi_ptrs_used; + + /* Must be set to zero */ + __u64 pi_reserved2[6]; + + /* + * An array of struct xfs_parent_ptr follows the header + * information. Use xfs_ppinfo_to_pp() to access the + * parent pointer array entries. + */ + struct xfs_parent_ptr pi_parents[]; +}; + +static inline size_t +xfs_pptr_info_sizeof(int nr_ptrs) +{ + return sizeof(struct xfs_pptr_info) + + (nr_ptrs * sizeof(struct xfs_parent_ptr)); +} + +static inline struct xfs_parent_ptr* +xfs_ppinfo_to_pp( + struct xfs_pptr_info *info, + int idx) +{ + return &info->pi_parents[idx]; +} + /* * ioctl limits */ @@ -797,6 +870,7 @@ struct xfs_scrub_metadata { /* XFS_IOC_GETFSMAP ------ hoisted 59 */ #define XFS_IOC_SCRUB_METADATA _IOWR('X', 60, struct xfs_scrub_metadata) #define XFS_IOC_AG_GEOMETRY _IOWR('X', 61, struct xfs_ag_geometry) +#define XFS_IOC_GETPARENTS _IOWR('X', 62, struct xfs_parent_ptr) /* * ioctl commands that replace IRIX syssgi()'s diff --git a/fs/xfs/libxfs/xfs_parent.c b/fs/xfs/libxfs/xfs_parent.c index 629762701952..9176adfaa9e8 100644 --- a/fs/xfs/libxfs/xfs_parent.c +++ b/fs/xfs/libxfs/xfs_parent.c @@ -29,6 +29,16 @@ struct kmem_cache *xfs_parent_intent_cache; +/* Initializes a xfs_parent_ptr from an xfs_parent_name_rec */ +void +xfs_init_parent_ptr(struct xfs_parent_ptr *xpp, + const struct xfs_parent_name_rec *rec) +{ + xpp->xpp_ino = be64_to_cpu(rec->p_ino); + xpp->xpp_gen = be32_to_cpu(rec->p_gen); + xpp->xpp_diroffset = be32_to_cpu(rec->p_diroffset); +} + /* * Parent pointer attribute handling. * diff --git a/fs/xfs/libxfs/xfs_parent.h b/fs/xfs/libxfs/xfs_parent.h index 039005883bb6..13040b9d8b08 100644 --- a/fs/xfs/libxfs/xfs_parent.h +++ b/fs/xfs/libxfs/xfs_parent.h @@ -25,6 +25,8 @@ struct xfs_parent_defer { void xfs_init_parent_name_rec(struct xfs_parent_name_rec *rec, struct xfs_inode *ip, uint32_t p_diroffset); +void xfs_init_parent_ptr(struct xfs_parent_ptr *xpp, + const struct xfs_parent_name_rec *rec); int __xfs_parent_init(struct xfs_mount *mp, bool grab_log, struct xfs_parent_defer **parentp); diff --git a/fs/xfs/xfs_ioctl.c b/fs/xfs/xfs_ioctl.c index 5cd5154d4d1e..df5a45b97f8f 100644 --- a/fs/xfs/xfs_ioctl.c +++ b/fs/xfs/xfs_ioctl.c @@ -37,6 +37,7 @@ #include "xfs_health.h" #include "xfs_reflink.h" #include "xfs_ioctl.h" +#include "xfs_parent_utils.h" #include "xfs_xattr.h" #include @@ -1675,6 +1676,96 @@ xfs_ioc_scrub_metadata( return 0; } +/* + * IOCTL routine to get the parent pointers of an inode and return it to user + * space. Caller must pass a buffer space containing a struct xfs_pptr_info, + * followed by a region large enough to contain an array of struct + * xfs_parent_ptr of a size specified in pi_ptrs_size. If the inode contains + * more parent pointers than can fit in the buffer space, caller may re-call + * the function using the returned pi_cursor to resume iteration. The + * number of xfs_parent_ptr returned will be stored in pi_ptrs_used. + * + * Returns 0 on success or non-zero on failure + */ +STATIC int +xfs_ioc_get_parent_pointer( + struct file *filp, + void __user *arg) +{ + struct xfs_pptr_info *ppi = NULL; + int error = 0; + struct xfs_inode *ip = XFS_I(file_inode(filp)); + struct xfs_mount *mp = ip->i_mount; + + if (!capable(CAP_SYS_ADMIN)) + return -EPERM; + + /* Allocate an xfs_pptr_info to put the user data */ + ppi = kmalloc(sizeof(struct xfs_pptr_info), 0); + if (!ppi) + return -ENOMEM; + + /* Copy the data from the user */ + error = copy_from_user(ppi, arg, sizeof(struct xfs_pptr_info)); + if (error) { + error = -EFAULT; + goto out; + } + + /* Check size of buffer requested by user */ + if (xfs_pptr_info_sizeof(ppi->pi_ptrs_size) > XFS_XATTR_LIST_MAX) { + error = -ENOMEM; + goto out; + } + + if (ppi->pi_flags & ~XFS_PPTR_FLAG_ALL) { + error = -EINVAL; + goto out; + } + ppi->pi_flags &= ~(XFS_PPTR_OFLAG_ROOT | XFS_PPTR_OFLAG_DONE); + + /* + * Now that we know how big the trailing buffer is, expand + * our kernel xfs_pptr_info to be the same size + */ + ppi = krealloc(ppi, xfs_pptr_info_sizeof(ppi->pi_ptrs_size), 0); + if (!ppi) + return -ENOMEM; + + if (ppi->pi_flags & XFS_PPTR_IFLAG_HANDLE) { + error = xfs_iget(mp, NULL, ppi->pi_handle.ha_fid.fid_ino, + 0, 0, &ip); + if (error) + goto out; + + if (VFS_I(ip)->i_generation != ppi->pi_handle.ha_fid.fid_gen) { + error = -EINVAL; + goto out; + } + } + + if (ip->i_ino == mp->m_sb.sb_rootino) + ppi->pi_flags |= XFS_PPTR_OFLAG_ROOT; + + /* Get the parent pointers */ + error = xfs_attr_get_parent_pointer(ip, ppi); + + if (error) + goto out; + + /* Copy the parent pointers back to the user */ + error = copy_to_user(arg, ppi, + xfs_pptr_info_sizeof(ppi->pi_ptrs_size)); + if (error) { + error = -EFAULT; + goto out; + } + +out: + kmem_free(ppi); + return error; +} + int xfs_ioc_swapext( xfs_swapext_t *sxp) @@ -1964,7 +2055,8 @@ xfs_file_ioctl( case XFS_IOC_FSGETXATTRA: return xfs_ioc_fsgetxattra(ip, arg); - + case XFS_IOC_GETPARENTS: + return xfs_ioc_get_parent_pointer(filp, arg); case XFS_IOC_GETBMAP: case XFS_IOC_GETBMAPA: case XFS_IOC_GETBMAPX: diff --git a/fs/xfs/xfs_ondisk.h b/fs/xfs/xfs_ondisk.h index 9737b5a9f405..6a6bd05c2a68 100644 --- a/fs/xfs/xfs_ondisk.h +++ b/fs/xfs/xfs_ondisk.h @@ -150,6 +150,10 @@ xfs_check_ondisk_structs(void) XFS_CHECK_OFFSET(struct xfs_efi_log_format_32, efi_extents, 16); XFS_CHECK_OFFSET(struct xfs_efi_log_format_64, efi_extents, 16); + /* parent pointer ioctls */ + XFS_CHECK_STRUCT_SIZE(struct xfs_parent_ptr, 280); + XFS_CHECK_STRUCT_SIZE(struct xfs_pptr_info, 104); + /* * The v5 superblock format extended several v4 header structures with * additional data. While new fields are only accessible on v5 diff --git a/fs/xfs/xfs_parent_utils.c b/fs/xfs/xfs_parent_utils.c new file mode 100644 index 000000000000..771279731d42 --- /dev/null +++ b/fs/xfs/xfs_parent_utils.c @@ -0,0 +1,126 @@ +// SPDX-License-Identifier: GPL-2.0 +/* + * Copyright (c) 2022 Oracle, Inc. + * All rights reserved. + */ +#include "xfs.h" +#include "xfs_fs.h" +#include "xfs_format.h" +#include "xfs_log_format.h" +#include "xfs_shared.h" +#include "xfs_trans_resv.h" +#include "xfs_mount.h" +#include "xfs_bmap_btree.h" +#include "xfs_inode.h" +#include "xfs_error.h" +#include "xfs_trace.h" +#include "xfs_trans.h" +#include "xfs_da_format.h" +#include "xfs_da_btree.h" +#include "xfs_attr.h" +#include "xfs_ioctl.h" +#include "xfs_parent.h" +#include "xfs_da_btree.h" +#include "xfs_parent_utils.h" + +/* + * Get the parent pointers for a given inode + * + * Returns 0 on success and non zero on error + */ +int +xfs_attr_get_parent_pointer( + struct xfs_inode *ip, + struct xfs_pptr_info *ppi) +{ + + struct xfs_attrlist *alist; + struct xfs_attrlist_ent *aent; + struct xfs_parent_ptr *xpp; + struct xfs_parent_name_rec *xpnr; + char *namebuf; + unsigned int namebuf_size; + int name_len, i, error = 0; + unsigned int lock_mode, flags = XFS_ATTR_PARENT; + struct xfs_attr_list_context context; + + /* Allocate a buffer to store the attribute names */ + namebuf_size = sizeof(struct xfs_attrlist) + + (ppi->pi_ptrs_size) * sizeof(struct xfs_attrlist_ent); + namebuf = kvzalloc(namebuf_size, GFP_KERNEL); + if (!namebuf) + return -ENOMEM; + + memset(&context, 0, sizeof(struct xfs_attr_list_context)); + error = xfs_ioc_attr_list_context_init(ip, namebuf, namebuf_size, 0, + &context); + if (error) + goto out_kfree; + + /* Copy the cursor provided by caller */ + memcpy(&context.cursor, &ppi->pi_cursor, + sizeof(struct xfs_attrlist_cursor)); + context.attr_filter = XFS_ATTR_PARENT; + + lock_mode = xfs_ilock_attr_map_shared(ip); + + error = xfs_attr_list_ilocked(&context); + if (error) + goto out_unlock; + + alist = (struct xfs_attrlist *)namebuf; + for (i = 0; i < alist->al_count; i++) { + struct xfs_da_args args = { + .geo = ip->i_mount->m_attr_geo, + .whichfork = XFS_ATTR_FORK, + .dp = ip, + .namelen = sizeof(struct xfs_parent_name_rec), + .attr_filter = flags, + }; + + xpp = xfs_ppinfo_to_pp(ppi, i); + memset(xpp, 0, sizeof(struct xfs_parent_ptr)); + aent = (struct xfs_attrlist_ent *) + &namebuf[alist->al_offset[i]]; + xpnr = (struct xfs_parent_name_rec *)(aent->a_name); + + if (aent->a_valuelen > XFS_PPTR_MAXNAMELEN) { + error = -EFSCORRUPTED; + goto out_unlock; + } + name_len = aent->a_valuelen; + + args.name = (char *)xpnr; + args.hashval = xfs_da_hashname(args.name, args.namelen), + args.value = (unsigned char *)(xpp->xpp_name); + args.valuelen = name_len; + + error = xfs_attr_get_ilocked(&args); + error = (error == -EEXIST ? 0 : error); + if (error) { + error = -EFSCORRUPTED; + goto out_unlock; + } + + xfs_init_parent_ptr(xpp, xpnr); + if (!xfs_verify_ino(args.dp->i_mount, xpp->xpp_ino)) { + error = -EFSCORRUPTED; + goto out_unlock; + } + } + ppi->pi_ptrs_used = alist->al_count; + if (!alist->al_more) + ppi->pi_flags |= XFS_PPTR_OFLAG_DONE; + + /* Update the caller with the current cursor position */ + memcpy(&ppi->pi_cursor, &context.cursor, + sizeof(struct xfs_attrlist_cursor)); + +out_unlock: + xfs_iunlock(ip, lock_mode); +out_kfree: + kvfree(namebuf); + + return error; +} + diff --git a/fs/xfs/xfs_parent_utils.h b/fs/xfs/xfs_parent_utils.h new file mode 100644 index 000000000000..ad60baee8b2a --- /dev/null +++ b/fs/xfs/xfs_parent_utils.h @@ -0,0 +1,11 @@ +// SPDX-License-Identifier: GPL-2.0 +/* + * Copyright (c) 2022 Oracle, Inc. + * All rights reserved. + */ +#ifndef __XFS_PARENT_UTILS_H__ +#define __XFS_PARENT_UTILS_H__ + +int xfs_attr_get_parent_pointer(struct xfs_inode *ip, + struct xfs_pptr_info *ppi); +#endif /* __XFS_PARENT_UTILS_H__ */