diff options
Diffstat (limited to 'fs/block_dev.c')
| -rw-r--r-- | fs/block_dev.c | 40 |
1 files changed, 35 insertions, 5 deletions
diff --git a/fs/block_dev.c b/fs/block_dev.c index 99e0ae1..ac7031f 100644 --- a/fs/block_dev.c +++ b/fs/block_dev.c @@ -326,12 +326,13 @@ static struct file_system_type bd_type = { .kill_sb = kill_anon_super, }; -static struct vfsmount *bd_mnt __read_mostly; -struct super_block *blockdev_superblock; +struct super_block *blockdev_superblock __read_mostly; void __init bdev_cache_init(void) { int err; + struct vfsmount *bd_mnt; + bdev_cachep = kmem_cache_create("bdev_cache", sizeof(struct bdev_inode), 0, (SLAB_HWCACHE_ALIGN|SLAB_RECLAIM_ACCOUNT| SLAB_MEM_SPREAD|SLAB_PANIC), @@ -373,7 +374,7 @@ struct block_device *bdget(dev_t dev) struct block_device *bdev; struct inode *inode; - inode = iget5_locked(bd_mnt->mnt_sb, hash(dev), + inode = iget5_locked(blockdev_superblock, hash(dev), bdev_test, bdev_set, &dev); if (!inode) @@ -463,7 +464,7 @@ void bd_forget(struct inode *inode) spin_lock(&bdev_lock); if (inode->i_bdev) { - if (inode->i_sb != blockdev_superblock) + if (!sb_is_blkdev_sb(inode->i_sb)) bdev = inode->i_bdev; __bd_forget(inode); } @@ -1004,6 +1005,7 @@ static int __blkdev_get(struct block_device *bdev, fmode_t mode, int for_part) } lock_kernel(); + restart: ret = -ENXIO; disk = get_gendisk(bdev->bd_dev, &partno); @@ -1024,6 +1026,19 @@ static int __blkdev_get(struct block_device *bdev, fmode_t mode, int for_part) if (disk->fops->open) { ret = disk->fops->open(bdev, mode); + if (ret == -ERESTARTSYS) { + /* Lost a race with 'disk' being + * deleted, try again. + * See md.c + */ + disk_put_part(bdev->bd_part); + bdev->bd_part = NULL; + module_put(disk->fops->owner); + put_disk(disk); + bdev->bd_disk = NULL; + mutex_unlock(&bdev->bd_mutex); + goto restart; + } if (ret) goto out_clear; } @@ -1219,6 +1234,20 @@ static long block_ioctl(struct file *file, unsigned cmd, unsigned long arg) return blkdev_ioctl(bdev, mode, cmd, arg); } +/* + * Try to release a page associated with block device when the system + * is under memory pressure. + */ +static int blkdev_releasepage(struct page *page, gfp_t wait) +{ + struct super_block *super = BDEV_I(page->mapping->host)->bdev.bd_super; + + if (super && super->s_op->bdev_try_to_free_page) + return super->s_op->bdev_try_to_free_page(super, page, wait); + + return try_to_free_buffers(page); +} + static const struct address_space_operations def_blk_aops = { .readpage = blkdev_readpage, .writepage = blkdev_writepage, @@ -1226,6 +1255,7 @@ static const struct address_space_operations def_blk_aops = { .write_begin = blkdev_write_begin, .write_end = blkdev_write_end, .writepages = generic_writepages, + .releasepage = blkdev_releasepage, .direct_IO = blkdev_direct_IO, }; @@ -1261,7 +1291,7 @@ EXPORT_SYMBOL(ioctl_by_bdev); /** * lookup_bdev - lookup a struct block_device by name - * @path: special file representing the block device + * @pathname: special file representing the block device * * Get a reference to the blockdevice at @pathname in the current * namespace if possible and return it. Return ERR_PTR(error) |
