diff options
| -rw-r--r-- | block/bdev.c | 3 | ||||
| -rw-r--r-- | block/fops.c | 44 | ||||
| -rw-r--r-- | include/linux/blkdev.h | 1 |
3 files changed, 32 insertions, 16 deletions
diff --git a/block/bdev.c b/block/bdev.c index bdc7d739882b..4628dcb1da8a 100644 --- a/block/bdev.c +++ b/block/bdev.c @@ -844,6 +844,9 @@ struct bdev_handle *bdev_open_by_dev(dev_t dev, blk_mode_t mode, void *holder, } handle->bdev = bdev; handle->holder = holder; + if (holder) + mode |= BLK_OPEN_EXCL; + handle->mode = mode; return handle; } EXPORT_SYMBOL(bdev_open_by_dev); diff --git a/block/fops.c b/block/fops.c index 73e42742543f..0abaac705daf 100644 --- a/block/fops.c +++ b/block/fops.c @@ -542,15 +542,31 @@ static int blkdev_fsync(struct file *filp, loff_t start, loff_t end, return error; } +/** + * file_to_blk_mode - get block open flags from file flags + * @file: file whose open flags should be converted + * + * Look at file open flags and generate corresponding block open flags from + * them. The function works both for file just being open (e.g. during ->open + * callback) and for file that is already open. This is actually non-trivial + * (see comment in the function). + */ blk_mode_t file_to_blk_mode(struct file *file) { blk_mode_t mode = 0; + struct bdev_handle *handle = file->private_data; if (file->f_mode & FMODE_READ) mode |= BLK_OPEN_READ; if (file->f_mode & FMODE_WRITE) mode |= BLK_OPEN_WRITE; - if (file->private_data) + /* + * do_dentry_open() clears O_EXCL from f_flags, use handle->mode to + * determine whether the open was exclusive for already open files. + */ + if (handle) + mode |= handle->mode & BLK_OPEN_EXCL; + else if (file->f_flags & O_EXCL) mode |= BLK_OPEN_EXCL; if (file->f_flags & O_NDELAY) mode |= BLK_OPEN_NDELAY; @@ -568,7 +584,8 @@ blk_mode_t file_to_blk_mode(struct file *file) static int blkdev_open(struct inode *inode, struct file *filp) { - struct block_device *bdev; + struct bdev_handle *handle; + blk_mode_t mode; /* * Preserve backwards compatibility and allow large file access @@ -579,29 +596,24 @@ static int blkdev_open(struct inode *inode, struct file *filp) filp->f_flags |= O_LARGEFILE; filp->f_mode |= FMODE_BUF_RASYNC | FMODE_CAN_ODIRECT; - /* - * Use the file private data to store the holder for exclusive openes. - * file_to_blk_mode relies on it being present to set BLK_OPEN_EXCL. - */ - if (filp->f_flags & O_EXCL) - filp->private_data = filp; - - bdev = blkdev_get_by_dev(inode->i_rdev, file_to_blk_mode(filp), - filp->private_data, NULL); - if (IS_ERR(bdev)) - return PTR_ERR(bdev); + mode = file_to_blk_mode(filp); + handle = bdev_open_by_dev(inode->i_rdev, mode, + mode & BLK_OPEN_EXCL ? filp : NULL, NULL); + if (IS_ERR(handle)) + return PTR_ERR(handle); - if (bdev_nowait(bdev)) + if (bdev_nowait(handle->bdev)) filp->f_mode |= FMODE_NOWAIT; - filp->f_mapping = bdev->bd_inode->i_mapping; + filp->f_mapping = handle->bdev->bd_inode->i_mapping; filp->f_wb_err = filemap_sample_wb_err(filp->f_mapping); + filp->private_data = handle; return 0; } static int blkdev_release(struct inode *inode, struct file *filp) { - blkdev_put(I_BDEV(filp->f_mapping->host), filp->private_data); + bdev_release(filp->private_data); return 0; } diff --git a/include/linux/blkdev.h b/include/linux/blkdev.h index 03d3adc3ff34..51fa7ffdee83 100644 --- a/include/linux/blkdev.h +++ b/include/linux/blkdev.h @@ -1482,6 +1482,7 @@ extern const struct blk_holder_ops fs_holder_ops; struct bdev_handle { struct block_device *bdev; void *holder; + blk_mode_t mode; }; struct block_device *blkdev_get_by_dev(dev_t dev, blk_mode_t mode, void *holder, |