[v3] efs: convert efs to use the new mount api

Commit Message

Bill O'Donnell March 4, 2024, 4:03 p.m. UTC

Convert the efs filesystem to use the new mount API.

Signed-off-by: Bill O'Donnell <[e-mail]>
---

Changelog:
v3: efs_fill_super: when setting blocksize use invalf(fc...) as return
    instead of -EINVAL. Remove unneeded efs_free_fc().
    In efs_reconfigure, add fc->sb_flags |= SB_RDONLY.
    Remove unused efs_context struct.

v2: Remove efs_param_spec and efs_parse_param, since no mount options.

---
 fs/efs/super.c | 78 ++++++++++++++++++++++++++++++--------------------
 1 file changed, 47 insertions(+), 31 deletions(-)

Comments

Eric Sandeen March 4, 2024, 7:04 p.m. UTC | #1

On 3/4/24 10:03 AM, Bill O'Donnell wrote:
> Convert the efs filesystem to use the new mount API.
> 
> Signed-off-by: Bill O'Donnell <[e-mail]>

This looks fine to me now.

Going forward, I might try to structure the changes so that
_reconfigure() stays in the same place as _remount_fs(), and
_get_tree stays in the same place as _mount(), when possible -
it makes the patch a little easier to review. But that's just a
minor suggestion.

Reviewed-by: Eric Sandeen <[e-mail]>

Christian Brauner March 5, 2024, 11:15 a.m. UTC | #2

On Mon, 04 Mar 2024 10:03:06 -0600, Bill O'Donnell wrote:
> Convert the efs filesystem to use the new mount API.
> 
> 

Applied to the vfs.mount.api branch of the vfs/vfs.git tree.
Patches in the vfs.mount.api branch should appear in linux-next soon.

Please report any outstanding bugs that were missed during review in a
new review to the original patch series allowing us to drop it.

It's encouraged to provide Acked-bys and Reviewed-bys even though the
patch has now been applied. If possible patch trailers will be updated.

Note that commit hashes shown below are subject to change due to rebase,
trailer updates or similar. If in doubt, please check the listed branch.

tree:   https://git.kernel.org/pub/scm/linux/kernel/git/vfs/vfs.git
branch: vfs.mount.api

[1/1] efs: convert efs to use the new mount api
      https://git.kernel.org/vfs/vfs/c/d5b1a5042b4a

Patch

diff --git a/fs/efs/super.c b/fs/efs/super.c
index f17fdac76b2e..5584248fccb4 100644
--- a/fs/efs/super.c
+++ b/fs/efs/super.c
@@ -14,19 +14,13 @@ 
 #include <linux/buffer_head.h>
 #include <linux/vfs.h>
 #include <linux/blkdev.h>
-
+#include <linux/fs_context.h>
 #include "efs.h"
 #include <linux/efs_vh.h>
 #include <linux/efs_fs_sb.h>
 
 static int efs_statfs(struct dentry *dentry, struct kstatfs *buf);
-static int efs_fill_super(struct super_block *s, void *d, int silent);
-
-static struct dentry *efs_mount(struct file_system_type *fs_type,
-	int flags, const char *dev_name, void *data)
-{
-	return mount_bdev(fs_type, flags, dev_name, data, efs_fill_super);
-}
+static int efs_init_fs_context(struct fs_context *fc);
 
 static void efs_kill_sb(struct super_block *s)
 {
@@ -35,15 +29,6 @@  static void efs_kill_sb(struct super_block *s)
 	kfree(sbi);
 }
 
-static struct file_system_type efs_fs_type = {
-	.owner		= THIS_MODULE,
-	.name		= "efs",
-	.mount		= efs_mount,
-	.kill_sb	= efs_kill_sb,
-	.fs_flags	= FS_REQUIRES_DEV,
-};
-MODULE_ALIAS_FS("efs");
-
 static struct pt_types sgi_pt_types[] = {
 	{0x00,		"SGI vh"},
 	{0x01,		"SGI trkrepl"},
@@ -63,6 +48,17 @@  static struct pt_types sgi_pt_types[] = {
 	{0,		NULL}
 };
 
+/*
+ * File system definition and registration.
+ */
+static struct file_system_type efs_fs_type = {
+	.owner			= THIS_MODULE,
+	.name			= "efs",
+	.kill_sb		= efs_kill_sb,
+	.fs_flags		= FS_REQUIRES_DEV,
+	.init_fs_context	= efs_init_fs_context,
+};
+MODULE_ALIAS_FS("efs");
 
 static struct kmem_cache * efs_inode_cachep;
 
@@ -108,18 +104,10 @@  static void destroy_inodecache(void)
 	kmem_cache_destroy(efs_inode_cachep);
 }
 
-static int efs_remount(struct super_block *sb, int *flags, char *data)
-{
-	sync_filesystem(sb);
-	*flags |= SB_RDONLY;
-	return 0;
-}
-
 static const struct super_operations efs_superblock_operations = {
 	.alloc_inode	= efs_alloc_inode,
 	.free_inode	= efs_free_inode,
 	.statfs		= efs_statfs,
-	.remount_fs	= efs_remount,
 };
 
 static const struct export_operations efs_export_ops = {
@@ -249,26 +237,27 @@  static int efs_validate_super(struct efs_sb_info *sb, struct efs_super *super) {
 	return 0;    
 }
 
-static int efs_fill_super(struct super_block *s, void *d, int silent)
+static int efs_fill_super(struct super_block *s, struct fs_context *fc)
 {
 	struct efs_sb_info *sb;
 	struct buffer_head *bh;
 	struct inode *root;
 
- 	sb = kzalloc(sizeof(struct efs_sb_info), GFP_KERNEL);
+	sb = kzalloc(sizeof(struct efs_sb_info), GFP_KERNEL);
 	if (!sb)
 		return -ENOMEM;
 	s->s_fs_info = sb;
 	s->s_time_min = 0;
 	s->s_time_max = U32_MAX;
- 
+
 	s->s_magic		= EFS_SUPER_MAGIC;
 	if (!sb_set_blocksize(s, EFS_BLOCKSIZE)) {
 		pr_err("device does not support %d byte blocks\n",
 			EFS_BLOCKSIZE);
-		return -EINVAL;
+		return invalf(fc, "device does not support %d byte blocks\n",
+			      EFS_BLOCKSIZE);
 	}
-  
+
 	/* read the vh (volume header) block */
 	bh = sb_bread(s, 0);
 
@@ -294,7 +283,7 @@  static int efs_fill_super(struct super_block *s, void *d, int silent)
 		pr_err("cannot read superblock\n");
 		return -EIO;
 	}
-		
+
 	if (efs_validate_super(sb, (struct efs_super *) bh->b_data)) {
 #ifdef DEBUG
 		pr_warn("invalid superblock at block %u\n",
@@ -328,6 +317,33 @@  static int efs_fill_super(struct super_block *s, void *d, int silent)
 	return 0;
 }
 
+static int efs_get_tree(struct fs_context *fc)
+{
+	return get_tree_bdev(fc, efs_fill_super);
+}
+
+static int efs_reconfigure(struct fs_context *fc)
+{
+	sync_filesystem(fc->root->d_sb);
+	fc->sb_flags |= SB_RDONLY;
+	return 0;
+}
+
+static const struct fs_context_operations efs_context_opts = {
+	.get_tree	= efs_get_tree,
+	.reconfigure	= efs_reconfigure,
+};
+
+/*
+ * Set up the filesystem mount context.
+ */
+static int efs_init_fs_context(struct fs_context *fc)
+{
+	fc->ops = &efs_context_opts;
+
+	return 0;
+}
+
 static int efs_statfs(struct dentry *dentry, struct kstatfs *buf) {
 	struct super_block *sb = dentry->d_sb;
 	struct efs_sb_info *sbi = SUPER_INFO(sb);