This is a note to let you know that I've just added the patch titled
block: Provide bdev_open_* functions
to the 6.6-stable tree which can be found at:
http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary
The filename of the patch is:
block-provide-bdev_open_-functions.patch
and it can be found in the queue-6.6 subdirectory.
If you, or anyone else, feels it should not be added to the stable tree,
please let <stable@xxxxxxxxxxxxxxx> know about it.
commit 6c40ef187a09262b1d059b832050b50577ffcb5b
Author: Jan Kara <jack@xxxxxxx>
Date: Wed Sep 27 11:34:07 2023 +0200
block: Provide bdev_open_* functions
[ Upstream commit e719b4d156749f02eafed31a3c515f2aa9dcc72a ]
Create struct bdev_handle that contains all parameters that need to be
passed to blkdev_put() and provide bdev_open_* functions that return
this structure instead of plain bdev pointer. This will eventually allow
us to pass one more argument to blkdev_put() (renamed to bdev_release())
without too much hassle.
Acked-by: Christoph Hellwig <hch@xxxxxx>
Reviewed-by: Christian Brauner <brauner@xxxxxxxxxx>
Signed-off-by: Jan Kara <jack@xxxxxxx>
Link: https://lore.kernel.org/r/20230927093442.25915-1-jack@xxxxxxx
Signed-off-by: Christian Brauner <brauner@xxxxxxxxxx>
Stable-dep-of: 0f28be64d132 ("erofs: fix lockdep false positives on initializing erofs_pseudo_mnt")
Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx>
diff --git a/block/bdev.c b/block/bdev.c
index 04dba25b0019e..5a54977518eea 100644
--- a/block/bdev.c
+++ b/block/bdev.c
@@ -831,6 +831,25 @@ struct block_device *blkdev_get_by_dev(dev_t dev, blk_mode_t mode, void *holder,
}
EXPORT_SYMBOL(blkdev_get_by_dev);
+struct bdev_handle *bdev_open_by_dev(dev_t dev, blk_mode_t mode, void *holder,
+ const struct blk_holder_ops *hops)
+{
+ struct bdev_handle *handle = kmalloc(sizeof(*handle), GFP_KERNEL);
+ struct block_device *bdev;
+
+ if (!handle)
+ return ERR_PTR(-ENOMEM);
+ bdev = blkdev_get_by_dev(dev, mode, holder, hops);
+ if (IS_ERR(bdev)) {
+ kfree(handle);
+ return ERR_CAST(bdev);
+ }
+ handle->bdev = bdev;
+ handle->holder = holder;
+ return handle;
+}
+EXPORT_SYMBOL(bdev_open_by_dev);
+
/**
* blkdev_get_by_path - open a block device by name
* @path: path to the block device to open
@@ -869,6 +888,28 @@ struct block_device *blkdev_get_by_path(const char *path, blk_mode_t mode,
}
EXPORT_SYMBOL(blkdev_get_by_path);
+struct bdev_handle *bdev_open_by_path(const char *path, blk_mode_t mode,
+ void *holder, const struct blk_holder_ops *hops)
+{
+ struct bdev_handle *handle;
+ dev_t dev;
+ int error;
+
+ error = lookup_bdev(path, &dev);
+ if (error)
+ return ERR_PTR(error);
+
+ handle = bdev_open_by_dev(dev, mode, holder, hops);
+ if (!IS_ERR(handle) && (mode & BLK_OPEN_WRITE) &&
+ bdev_read_only(handle->bdev)) {
+ bdev_release(handle);
+ return ERR_PTR(-EACCES);
+ }
+
+ return handle;
+}
+EXPORT_SYMBOL(bdev_open_by_path);
+
void blkdev_put(struct block_device *bdev, void *holder)
{
struct gendisk *disk = bdev->bd_disk;
@@ -905,6 +946,13 @@ void blkdev_put(struct block_device *bdev, void *holder)
}
EXPORT_SYMBOL(blkdev_put);
+void bdev_release(struct bdev_handle *handle)
+{
+ blkdev_put(handle->bdev, handle->holder);
+ kfree(handle);
+}
+EXPORT_SYMBOL(bdev_release);
+
/**
* lookup_bdev() - Look up a struct block_device by name.
* @pathname: Name of the block device in the filesystem.
diff --git a/include/linux/blkdev.h b/include/linux/blkdev.h
index f59fcd5b499a5..5b6e86b2c37a5 100644
--- a/include/linux/blkdev.h
+++ b/include/linux/blkdev.h
@@ -1479,14 +1479,24 @@ extern const struct blk_holder_ops fs_holder_ops;
#define sb_open_mode(flags) \
(BLK_OPEN_READ | (((flags) & SB_RDONLY) ? 0 : BLK_OPEN_WRITE))
+struct bdev_handle {
+ struct block_device *bdev;
+ void *holder;
+};
+
struct block_device *blkdev_get_by_dev(dev_t dev, blk_mode_t mode, void *holder,
const struct blk_holder_ops *hops);
struct block_device *blkdev_get_by_path(const char *path, blk_mode_t mode,
void *holder, const struct blk_holder_ops *hops);
+struct bdev_handle *bdev_open_by_dev(dev_t dev, blk_mode_t mode, void *holder,
+ const struct blk_holder_ops *hops);
+struct bdev_handle *bdev_open_by_path(const char *path, blk_mode_t mode,
+ void *holder, const struct blk_holder_ops *hops);
int bd_prepare_to_claim(struct block_device *bdev, void *holder,
const struct blk_holder_ops *hops);
void bd_abort_claiming(struct block_device *bdev, void *holder);
void blkdev_put(struct block_device *bdev, void *holder);
+void bdev_release(struct bdev_handle *handle);
/* just for blk-cgroup, don't use elsewhere */
struct block_device *blkdev_get_no_open(dev_t dev);
