bdev: remove bdev pointer from struct bdev_handle

We can always go directly via:

* I_BDEV(bdev_file->f_inode)
* I_BDEV(bdev_file->f_mapping->host)

So keeping struct bdev in struct bdev_handle is redundant.

Link: https://lore.kernel.org/r/20240123-vfs-bdev-file-v2-30-adbd023e19cc@kernel.org
Reviewed-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Jan Kara <jack@suse.cz>
Signed-off-by: Christian Brauner <brauner@kernel.org>

diff --git a/block/bdev.c b/block/bdev.c
index 8f33f160e92328f9dad30564747a6d6266c41d0c..4e4527c5df00b58085dcf95068c075915a86530d 100644 (file)
--- a/block/bdev.c
+++ b/block/bdev.c
@@ -51,8 +51,7 @@ EXPORT_SYMBOL(I_BDEV);
 
 struct block_device *file_bdev(struct file *bdev_file)
 {
-       struct bdev_handle *handle = bdev_file->private_data;
-       return handle->bdev;
+       return I_BDEV(bdev_file->f_mapping->host);
 }
 EXPORT_SYMBOL(file_bdev);
 
@@ -891,7 +890,6 @@ int bdev_open(struct block_device *bdev, blk_mode_t mode, void *holder,
 
        if (unblock_events)
                disk_unblock_events(disk);
-       handle->bdev = bdev;
        handle->holder = holder;
        handle->mode = mode;
 
@@ -899,7 +897,7 @@ int bdev_open(struct block_device *bdev, blk_mode_t mode, void *holder,
        bdev_file->f_mode |= FMODE_BUF_RASYNC | FMODE_CAN_ODIRECT;
        if (bdev_nowait(bdev))
                bdev_file->f_mode |= FMODE_NOWAIT;
-       bdev_file->f_mapping = handle->bdev->bd_inode->i_mapping;
+       bdev_file->f_mapping = bdev->bd_inode->i_mapping;
        bdev_file->f_wb_err = filemap_sample_wb_err(bdev_file->f_mapping);
        bdev_file->private_data = handle;
 
@@ -985,7 +983,7 @@ struct file *bdev_file_open_by_path(const char *path, blk_mode_t mode,
                                    void *holder,
                                    const struct blk_holder_ops *hops)
 {
-       struct file *bdev_file;
+       struct file *file;
        dev_t dev;
        int error;
 
@@ -993,22 +991,22 @@ struct file *bdev_file_open_by_path(const char *path, blk_mode_t mode,
        if (error)
                return ERR_PTR(error);
 
-       bdev_file = bdev_file_open_by_dev(dev, mode, holder, hops);
-       if (!IS_ERR(bdev_file) && (mode & BLK_OPEN_WRITE)) {
-               struct bdev_handle *handle = bdev_file->private_data;
-               if (bdev_read_only(handle->bdev)) {
-                       fput(bdev_file);
-                       bdev_file = ERR_PTR(-EACCES);
+       file = bdev_file_open_by_dev(dev, mode, holder, hops);
+       if (!IS_ERR(file) && (mode & BLK_OPEN_WRITE)) {
+               if (bdev_read_only(file_bdev(file))) {
+                       fput(file);
+                       file = ERR_PTR(-EACCES);
                }
        }
 
-       return bdev_file;
+       return file;
 }
 EXPORT_SYMBOL(bdev_file_open_by_path);
 
-void bdev_release(struct bdev_handle *handle)
+void bdev_release(struct file *bdev_file)
 {
-       struct block_device *bdev = handle->bdev;
+       struct block_device *bdev = file_bdev(bdev_file);
+       struct bdev_handle *handle = bdev_file->private_data;
        struct gendisk *disk = bdev->bd_disk;
 
        /*

diff --git a/block/blk.h b/block/blk.h
index 19b15870284f43579f80dfe5755959b82601250c..7ca24814f3a0dbdb43560d40a001836f84897a82 100644 (file)
--- a/block/blk.h
+++ b/block/blk.h
@@ -26,7 +26,6 @@ struct blk_flush_queue {
 };
 
 struct bdev_handle {
-       struct block_device *bdev;
        void *holder;
        blk_mode_t mode;
 };
@@ -522,7 +521,7 @@ static inline int req_ref_read(struct request *req)
        return atomic_read(&req->ref);
 }
 
-void bdev_release(struct bdev_handle *handle);
+void bdev_release(struct file *bdev_file);
 int bdev_open(struct block_device *bdev, blk_mode_t mode, void *holder,
              const struct blk_holder_ops *hops, struct file *bdev_file);
 int bdev_permission(dev_t dev, blk_mode_t mode, void *holder);

diff --git a/block/fops.c b/block/fops.c
index a1ba1a50ae7787259cbdba6740e8f8c9dde6dab4..aab9b89e4c77d82d88822f7cc01552a13966c7a0 100644 (file)
--- a/block/fops.c
+++ b/block/fops.c
@@ -623,7 +623,7 @@ static int blkdev_open(struct inode *inode, struct file *filp)
 static int blkdev_release(struct inode *inode, struct file *filp)
 {
        if (filp->private_data)
-               bdev_release(filp->private_data);
+               bdev_release(filp);
        return 0;
 }