Instead of tricks with struct bdev_inode, just openly place the inode inside struct block_device. First, it allows us to inline I_BDEV, which is simple but non-inline nature of it impacts performance. Also, make it possible to get rid of ->bd_inode pointer and hooping with extra indirection, the amount of which became a noticeable problem for the block layer. Signed-off-by: Pavel Begunkov <asml.silence@xxxxxxxxx> --- block/bdev.c | 44 ++++++++++----------------------------- block/fops.c | 20 +++++++----------- include/linux/blk_types.h | 1 + include/linux/blkdev.h | 8 +++++-- 4 files changed, 26 insertions(+), 47 deletions(-) diff --git a/block/bdev.c b/block/bdev.c index 567534c63f3d..541e24d240d1 100644 --- a/block/bdev.c +++ b/block/bdev.c @@ -30,22 +30,6 @@ #include "../fs/internal.h" #include "blk.h" -struct bdev_inode { - struct block_device bdev; - struct inode vfs_inode; -}; - -static inline struct bdev_inode *BDEV_I(struct inode *inode) -{ - return container_of(inode, struct bdev_inode, vfs_inode); -} - -struct block_device *I_BDEV(struct inode *inode) -{ - return &BDEV_I(inode)->bdev; -} -EXPORT_SYMBOL(I_BDEV); - static void bdev_write_inode(struct block_device *bdev) { struct inode *inode = bdev->bd_inode; @@ -389,12 +373,13 @@ static struct kmem_cache * bdev_cachep __read_mostly; static struct inode *bdev_alloc_inode(struct super_block *sb) { - struct bdev_inode *ei = kmem_cache_alloc(bdev_cachep, GFP_KERNEL); + struct block_device *bdev = kmem_cache_alloc(bdev_cachep, GFP_KERNEL); - if (!ei) + if (!bdev) return NULL; - memset(&ei->bdev, 0, sizeof(ei->bdev)); - return &ei->vfs_inode; + memset(bdev, 0, sizeof(*bdev)); + inode_init_once(&bdev->inode); + return &bdev->inode; } static void bdev_free_inode(struct inode *inode) @@ -413,14 +398,7 @@ static void bdev_free_inode(struct inode *inode) if (MAJOR(bdev->bd_dev) == BLOCK_EXT_MAJOR) blk_free_ext_minor(MINOR(bdev->bd_dev)); - kmem_cache_free(bdev_cachep, BDEV_I(inode)); -} - -static void init_once(void *data) -{ - struct bdev_inode *ei = data; - - inode_init_once(&ei->vfs_inode); + kmem_cache_free(bdev_cachep, bdev); } static void bdev_evict_inode(struct inode *inode) @@ -462,10 +440,10 @@ void __init bdev_cache_init(void) int err; static 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_ACCOUNT|SLAB_PANIC), - init_once); + bdev_cachep = kmem_cache_create("bdev_cache", + sizeof(struct block_device), 0, + (SLAB_HWCACHE_ALIGN|SLAB_RECLAIM_ACCOUNT| + SLAB_MEM_SPREAD|SLAB_ACCOUNT|SLAB_PANIC), NULL); err = register_filesystem(&bd_type); if (err) panic("Cannot register bdev pseudo-fs"); @@ -744,7 +722,7 @@ struct block_device *blkdev_get_no_open(dev_t dev) } /* switch from the inode reference to a device mode one: */ - bdev = &BDEV_I(inode)->bdev; + bdev = I_BDEV(inode); if (!kobject_get_unless_zero(&bdev->bd_device.kobj)) bdev = NULL; iput(inode); diff --git a/block/fops.c b/block/fops.c index c71e91cd6bcb..9ae795f27f74 100644 --- a/block/fops.c +++ b/block/fops.c @@ -17,11 +17,6 @@ #include <linux/fs.h> #include "blk.h" -static inline struct inode *bdev_file_inode(struct file *file) -{ - return file->f_mapping->host; -} - static int blkdev_get_block(struct inode *inode, sector_t iblock, struct buffer_head *bh, int create) { @@ -390,7 +385,8 @@ const struct address_space_operations def_blk_aops = { */ static loff_t blkdev_llseek(struct file *file, loff_t offset, int whence) { - struct inode *bd_inode = bdev_file_inode(file); + struct block_device *bdev = file->private_data; + struct inode *bd_inode = &bdev->inode; loff_t retval; inode_lock(bd_inode); @@ -446,7 +442,7 @@ static int blkdev_open(struct inode *inode, struct file *filp) return PTR_ERR(bdev); filp->private_data = bdev; - filp->f_mapping = bdev->bd_inode->i_mapping; + filp->f_mapping = bdev->inode.i_mapping; filp->f_wb_err = filemap_sample_wb_err(filp->f_mapping); return 0; } @@ -469,7 +465,7 @@ static int blkdev_close(struct inode *inode, struct file *filp) static ssize_t blkdev_write_iter(struct kiocb *iocb, struct iov_iter *from) { struct block_device *bdev = iocb->ki_filp->private_data; - struct inode *bd_inode = bdev->bd_inode; + struct inode *bd_inode = &bdev->inode; loff_t size = i_size_read(bd_inode); struct blk_plug plug; size_t shorted = 0; @@ -508,7 +504,7 @@ static ssize_t blkdev_write_iter(struct kiocb *iocb, struct iov_iter *from) static ssize_t blkdev_read_iter(struct kiocb *iocb, struct iov_iter *to) { struct block_device *bdev = iocb->ki_filp->private_data; - loff_t size = i_size_read(bdev->bd_inode); + loff_t size = i_size_read(&bdev->inode); loff_t pos = iocb->ki_pos; size_t shorted = 0; ssize_t ret; @@ -534,8 +530,8 @@ static ssize_t blkdev_read_iter(struct kiocb *iocb, struct iov_iter *to) static long blkdev_fallocate(struct file *file, int mode, loff_t start, loff_t len) { - struct inode *inode = bdev_file_inode(file); - struct block_device *bdev = I_BDEV(inode); + struct block_device *bdev = file->private_data; + struct inode *inode = &bdev->inode; loff_t end = start + len - 1; loff_t isize; int error; @@ -545,7 +541,7 @@ static long blkdev_fallocate(struct file *file, int mode, loff_t start, return -EOPNOTSUPP; /* Don't go off the end of the device. */ - isize = i_size_read(bdev->bd_inode); + isize = i_size_read(inode); if (start >= isize) return -EINVAL; if (end >= isize) { diff --git a/include/linux/blk_types.h b/include/linux/blk_types.h index 3b967053e9f5..e94d08eb4fa9 100644 --- a/include/linux/blk_types.h +++ b/include/linux/blk_types.h @@ -49,6 +49,7 @@ struct block_device { #ifdef CONFIG_FAIL_MAKE_REQUEST bool bd_make_it_fail; #endif + struct inode inode; } __randomize_layout; #define bdev_whole(_bdev) \ diff --git a/include/linux/blkdev.h b/include/linux/blkdev.h index 17705c970d7e..75d2682a8a55 100644 --- a/include/linux/blkdev.h +++ b/include/linux/blkdev.h @@ -1141,7 +1141,7 @@ static inline unsigned int blksize_bits(unsigned int size) static inline unsigned int block_size(struct block_device *bdev) { - return 1 << bdev->bd_inode->i_blkbits; + return 1 << bdev->inode.i_blkbits; } int kblockd_schedule_work(struct work_struct *work); @@ -1271,10 +1271,14 @@ void blkdev_put_no_open(struct block_device *bdev); struct block_device *bdev_alloc(struct gendisk *disk, u8 partno); void bdev_add(struct block_device *bdev, dev_t dev); -struct block_device *I_BDEV(struct inode *inode); int truncate_bdev_range(struct block_device *bdev, fmode_t mode, loff_t lstart, loff_t lend); +static inline struct block_device *I_BDEV(struct inode *inode) +{ + return container_of(inode, struct block_device, inode); +} + #ifdef CONFIG_BLOCK void invalidate_bdev(struct block_device *bdev); int sync_blockdev(struct block_device *bdev); -- 2.33.0