summaryrefslogtreecommitdiffstats
path: root/fs/super.c
diff options
context:
space:
mode:
authorChristian Brauner <brauner@kernel.org>2024-02-08 18:47:35 +0100
committerChristian Brauner <brauner@kernel.org>2024-02-25 12:05:21 +0100
commitf3a608827d1f8de0dd12813e8d9c6803fe64e119 (patch)
tree7072a00135288537c56348d8abf4ada7cd5fac7d /fs/super.c
parentfile: add alloc_file_pseudo_noaccount() (diff)
downloadlinux-f3a608827d1f8de0dd12813e8d9c6803fe64e119.tar.xz
linux-f3a608827d1f8de0dd12813e8d9c6803fe64e119.zip
bdev: open block device as files
Add two new helpers to allow opening block devices as files. This is not the final infrastructure. This still opens the block device before opening a struct a file. Until we have removed all references to struct bdev_handle we can't switch the order: * Introduce blk_to_file_flags() to translate from block specific to flags usable to pen a new file. * Introduce bdev_file_open_by_{dev,path}(). * Introduce temporary sb_bdev_handle() helper to retrieve a struct bdev_handle from a block device file and update places that directly reference struct bdev_handle to rely on it. * Don't count block device openes against the number of open files. A bdev_file_open_by_{dev,path}() file is never installed into any file descriptor table. One idea that came to mind was to use kernel_tmpfile_open() which would require us to pass a path and it would then call do_dentry_open() going through the regular fops->open::blkdev_open() path. But then we're back to the problem of routing block specific flags such as BLK_OPEN_RESTRICT_WRITES through the open path and would have to waste FMODE_* flags every time we add a new one. With this we can avoid using a flag bit and we have more leeway in how we open block devices from bdev_open_by_{dev,path}(). Link: https://lore.kernel.org/r/20240123-vfs-bdev-file-v2-1-adbd023e19cc@kernel.org Signed-off-by: Christian Brauner <brauner@kernel.org>
Diffstat (limited to 'fs/super.c')
-rw-r--r--fs/super.c18
1 files changed, 9 insertions, 9 deletions
diff --git a/fs/super.c b/fs/super.c
index d35e85295489..08dcc3371aa0 100644
--- a/fs/super.c
+++ b/fs/super.c
@@ -1532,16 +1532,16 @@ int setup_bdev_super(struct super_block *sb, int sb_flags,
struct fs_context *fc)
{
blk_mode_t mode = sb_open_mode(sb_flags);
- struct bdev_handle *bdev_handle;
+ struct file *bdev_file;
struct block_device *bdev;
- bdev_handle = bdev_open_by_dev(sb->s_dev, mode, sb, &fs_holder_ops);
- if (IS_ERR(bdev_handle)) {
+ bdev_file = bdev_file_open_by_dev(sb->s_dev, mode, sb, &fs_holder_ops);
+ if (IS_ERR(bdev_file)) {
if (fc)
errorf(fc, "%s: Can't open blockdev", fc->source);
- return PTR_ERR(bdev_handle);
+ return PTR_ERR(bdev_file);
}
- bdev = bdev_handle->bdev;
+ bdev = file_bdev(bdev_file);
/*
* This really should be in blkdev_get_by_dev, but right now can't due
@@ -1549,7 +1549,7 @@ int setup_bdev_super(struct super_block *sb, int sb_flags,
* writable from userspace even for a read-only block device.
*/
if ((mode & BLK_OPEN_WRITE) && bdev_read_only(bdev)) {
- bdev_release(bdev_handle);
+ fput(bdev_file);
return -EACCES;
}
@@ -1560,11 +1560,11 @@ int setup_bdev_super(struct super_block *sb, int sb_flags,
if (atomic_read(&bdev->bd_fsfreeze_count) > 0) {
if (fc)
warnf(fc, "%pg: Can't mount, blockdev is frozen", bdev);
- bdev_release(bdev_handle);
+ fput(bdev_file);
return -EBUSY;
}
spin_lock(&sb_lock);
- sb->s_bdev_handle = bdev_handle;
+ sb->s_bdev_file = bdev_file;
sb->s_bdev = bdev;
sb->s_bdi = bdi_get(bdev->bd_disk->bdi);
if (bdev_stable_writes(bdev))
@@ -1680,7 +1680,7 @@ void kill_block_super(struct super_block *sb)
generic_shutdown_super(sb);
if (bdev) {
sync_blockdev(bdev);
- bdev_release(sb->s_bdev_handle);
+ fput(sb->s_bdev_file);
}
}