fs/super.c: introduce get_tree_bdev_flags()

As Allison reported [1], currently get_tree_bdev() will store
"Can't lookup blockdev" error message.  Although it makes sense for
pure bdev-based fses, this message may mislead users who try to use
EROFS file-backed mounts since get_tree_nodev() is used as a fallback
then.

Add get_tree_bdev_flags() to specify extensible flags [2] and
GET_TREE_BDEV_QUIET_LOOKUP to silence "Can't lookup blockdev" message
since it's misleading to EROFS file-backed mounts now.

[1] https://lore.kernel.org/r/CAOYeF9VQ8jKVmpy5Zy9DNhO6xmWSKMB-DO8yvBB0XvBE7=3Ugg@mail.gmail.com
[2] https://lore.kernel.org/r/ZwUkJEtwIpUA4qMz@infradead.org

Suggested-by: Christoph Hellwig <hch@infradead.org>
Signed-off-by: Gao Xiang <hsiangkao@linux.alibaba.com>
Link: https://lore.kernel.org/r/20241009033151.2334888-1-hsiangkao@linux.alibaba.com
Reviewed-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Jan Kara <jack@suse.cz>
Signed-off-by: Christian Brauner <brauner@kernel.org>
This commit is contained in:
Gao Xiang 2024-10-09 11:31:50 +08:00 committed by Christian Brauner
parent 42f7652d3e
commit 4021e68513
No known key found for this signature in database
GPG Key ID: 91C61BC06578DCA2
2 changed files with 26 additions and 6 deletions

View File

@ -1596,13 +1596,14 @@ int setup_bdev_super(struct super_block *sb, int sb_flags,
EXPORT_SYMBOL_GPL(setup_bdev_super); EXPORT_SYMBOL_GPL(setup_bdev_super);
/** /**
* get_tree_bdev - Get a superblock based on a single block device * get_tree_bdev_flags - Get a superblock based on a single block device
* @fc: The filesystem context holding the parameters * @fc: The filesystem context holding the parameters
* @fill_super: Helper to initialise a new superblock * @fill_super: Helper to initialise a new superblock
* @flags: GET_TREE_BDEV_* flags
*/ */
int get_tree_bdev(struct fs_context *fc, int get_tree_bdev_flags(struct fs_context *fc,
int (*fill_super)(struct super_block *, int (*fill_super)(struct super_block *sb,
struct fs_context *)) struct fs_context *fc), unsigned int flags)
{ {
struct super_block *s; struct super_block *s;
int error = 0; int error = 0;
@ -1613,10 +1614,10 @@ int get_tree_bdev(struct fs_context *fc,
error = lookup_bdev(fc->source, &dev); error = lookup_bdev(fc->source, &dev);
if (error) { if (error) {
if (!(flags & GET_TREE_BDEV_QUIET_LOOKUP))
errorf(fc, "%s: Can't lookup blockdev", fc->source); errorf(fc, "%s: Can't lookup blockdev", fc->source);
return error; return error;
} }
fc->sb_flags |= SB_NOSEC; fc->sb_flags |= SB_NOSEC;
s = sget_dev(fc, dev); s = sget_dev(fc, dev);
if (IS_ERR(s)) if (IS_ERR(s))
@ -1644,6 +1645,19 @@ int get_tree_bdev(struct fs_context *fc,
fc->root = dget(s->s_root); fc->root = dget(s->s_root);
return 0; return 0;
} }
EXPORT_SYMBOL_GPL(get_tree_bdev_flags);
/**
* get_tree_bdev - Get a superblock based on a single block device
* @fc: The filesystem context holding the parameters
* @fill_super: Helper to initialise a new superblock
*/
int get_tree_bdev(struct fs_context *fc,
int (*fill_super)(struct super_block *,
struct fs_context *))
{
return get_tree_bdev_flags(fc, fill_super, 0);
}
EXPORT_SYMBOL(get_tree_bdev); EXPORT_SYMBOL(get_tree_bdev);
static int test_bdev_super(struct super_block *s, void *data) static int test_bdev_super(struct super_block *s, void *data)

View File

@ -160,6 +160,12 @@ extern int get_tree_keyed(struct fs_context *fc,
int setup_bdev_super(struct super_block *sb, int sb_flags, int setup_bdev_super(struct super_block *sb, int sb_flags,
struct fs_context *fc); struct fs_context *fc);
#define GET_TREE_BDEV_QUIET_LOOKUP 0x0001
int get_tree_bdev_flags(struct fs_context *fc,
int (*fill_super)(struct super_block *sb,
struct fs_context *fc), unsigned int flags);
extern int get_tree_bdev(struct fs_context *fc, extern int get_tree_bdev(struct fs_context *fc,
int (*fill_super)(struct super_block *sb, int (*fill_super)(struct super_block *sb,
struct fs_context *fc)); struct fs_context *fc));