diff options
| -rw-r--r-- | block/Makefile | 2 | ||||
| -rw-r--r-- | block/blk.h | 2 | ||||
| -rw-r--r-- | block/fops.c | 640 | ||||
| -rw-r--r-- | fs/block_dev.c | 637 |
4 files changed, 643 insertions, 638 deletions
diff --git a/block/Makefile b/block/Makefile index 1d0d466f2182..a4d8d149670b 100644 --- a/block/Makefile +++ b/block/Makefile @@ -3,7 +3,7 @@ # Makefile for the kernel block layer # -obj-$(CONFIG_BLOCK) := bio.o elevator.o blk-core.o blk-sysfs.o \ +obj-$(CONFIG_BLOCK) := fops.o bio.o elevator.o blk-core.o blk-sysfs.o \ blk-flush.o blk-settings.o blk-ioc.o blk-map.o \ blk-exec.o blk-merge.o blk-timeout.o \ blk-lib.o blk-mq.o blk-mq-tag.o blk-stat.o \ diff --git a/block/blk.h b/block/blk.h index 8c96b0c90c48..7d2a0ba7ed21 100644 --- a/block/blk.h +++ b/block/blk.h @@ -373,4 +373,6 @@ static inline void bio_clear_hipri(struct bio *bio) bio->bi_opf &= ~REQ_HIPRI; } +extern const struct address_space_operations def_blk_aops; + #endif /* BLK_INTERNAL_H */ diff --git a/block/fops.c b/block/fops.c new file mode 100644 index 000000000000..ffce6f6c68dd --- /dev/null +++ b/block/fops.c @@ -0,0 +1,640 @@ +// SPDX-License-Identifier: GPL-2.0-only +/* + * Copyright (C) 1991, 1992 Linus Torvalds + * Copyright (C) 2001 Andrea Arcangeli <andrea@suse.de> SuSE + * Copyright (C) 2016 - 2020 Christoph Hellwig + */ +#include <linux/init.h> +#include <linux/mm.h> +#include <linux/blkdev.h> +#include <linux/buffer_head.h> +#include <linux/mpage.h> +#include <linux/uio.h> +#include <linux/namei.h> +#include <linux/task_io_accounting_ops.h> +#include <linux/falloc.h> +#include <linux/suspend.h> +#include "blk.h" + +static 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) +{ + bh->b_bdev = I_BDEV(inode); + bh->b_blocknr = iblock; + set_buffer_mapped(bh); + return 0; +} + +static unsigned int dio_bio_write_op(struct kiocb *iocb) +{ + unsigned int op = REQ_OP_WRITE | REQ_SYNC | REQ_IDLE; + + /* avoid the need for a I/O completion work item */ + if (iocb->ki_flags & IOCB_DSYNC) + op |= REQ_FUA; + return op; +} + +#define DIO_INLINE_BIO_VECS 4 + +static void blkdev_bio_end_io_simple(struct bio *bio) +{ + struct task_struct *waiter = bio->bi_private; + + WRITE_ONCE(bio->bi_private, NULL); + blk_wake_io_task(waiter); +} + +static ssize_t __blkdev_direct_IO_simple(struct kiocb *iocb, + struct iov_iter *iter, unsigned int nr_pages) +{ + struct file *file = iocb->ki_filp; + struct block_device *bdev = I_BDEV(bdev_file_inode(file)); + struct bio_vec inline_vecs[DIO_INLINE_BIO_VECS], *vecs; + loff_t pos = iocb->ki_pos; + bool should_dirty = false; + struct bio bio; + ssize_t ret; + blk_qc_t qc; + + if ((pos | iov_iter_alignment(iter)) & + (bdev_logical_block_size(bdev) - 1)) + return -EINVAL; + + if (nr_pages <= DIO_INLINE_BIO_VECS) + vecs = inline_vecs; + else { + vecs = kmalloc_array(nr_pages, sizeof(struct bio_vec), + GFP_KERNEL); + if (!vecs) + return -ENOMEM; + } + + bio_init(&bio, vecs, nr_pages); + bio_set_dev(&bio, bdev); + bio.bi_iter.bi_sector = pos >> 9; + bio.bi_write_hint = iocb->ki_hint; + bio.bi_private = current; + bio.bi_end_io = blkdev_bio_end_io_simple; + bio.bi_ioprio = iocb->ki_ioprio; + + ret = bio_iov_iter_get_pages(&bio, iter); + if (unlikely(ret)) + goto out; + ret = bio.bi_iter.bi_size; + + if (iov_iter_rw(iter) == READ) { + bio.bi_opf = REQ_OP_READ; + if (iter_is_iovec(iter)) + should_dirty = true; + } else { + bio.bi_opf = dio_bio_write_op(iocb); + task_io_account_write(ret); + } + if (iocb->ki_flags & IOCB_NOWAIT) + bio.bi_opf |= REQ_NOWAIT; + if (iocb->ki_flags & IOCB_HIPRI) + bio_set_polled(&bio, iocb); + + qc = submit_bio(&bio); + for (;;) { + set_current_state(TASK_UNINTERRUPTIBLE); + if (!READ_ONCE(bio.bi_private)) + break; + if (!(iocb->ki_flags & IOCB_HIPRI) || + !blk_poll(bdev_get_queue(bdev), qc, true)) + blk_io_schedule(); + } + __set_current_state(TASK_RUNNING); + + bio_release_pages(&bio, should_dirty); + if (unlikely(bio.bi_status)) + ret = blk_status_to_errno(bio.bi_status); + +out: + if (vecs != inline_vecs) + kfree(vecs); + + bio_uninit(&bio); + + return ret; +} + +struct blkdev_dio { + union { + struct kiocb *iocb; + struct task_struct *waiter; + }; + size_t size; + atomic_t ref; + bool multi_bio : 1; + bool should_dirty : 1; + bool is_sync : 1; + struct bio bio; +}; + +static struct bio_set blkdev_dio_pool; + +static int blkdev_iopoll(struct kiocb *kiocb, bool wait) +{ + struct block_device *bdev = I_BDEV(kiocb->ki_filp->f_mapping->host); + struct request_queue *q = bdev_get_queue(bdev); + + return blk_poll(q, READ_ONCE(kiocb->ki_cookie), wait); +} + +static void blkdev_bio_end_io(struct bio *bio) +{ + struct blkdev_dio *dio = bio->bi_private; + bool should_dirty = dio->should_dirty; + + if (bio->bi_status && !dio->bio.bi_status) + dio->bio.bi_status = bio->bi_status; + + if (!dio->multi_bio || atomic_dec_and_test(&dio->ref)) { + if (!dio->is_sync) { + struct kiocb *iocb = dio->iocb; + ssize_t ret; + + if (likely(!dio->bio.bi_status)) { + ret = dio->size; + iocb->ki_pos += ret; + } else { + ret = blk_status_to_errno(dio->bio.bi_status); + } + + dio->iocb->ki_complete(iocb, ret, 0); + if (dio->multi_bio) + bio_put(&dio->bio); + } else { + struct task_struct *waiter = dio->waiter; + + WRITE_ONCE(dio->waiter, NULL); + blk_wake_io_task(waiter); + } + } + + if (should_dirty) { + bio_check_pages_dirty(bio); + } else { + bio_release_pages(bio, false); + bio_put(bio); + } +} + +static ssize_t __blkdev_direct_IO(struct kiocb *iocb, struct iov_iter *iter, + unsigned int nr_pages) +{ + struct file *file = iocb->ki_filp; + struct inode *inode = bdev_file_inode(file); + struct block_device *bdev = I_BDEV(inode); + struct blk_plug plug; + struct blkdev_dio *dio; + struct bio *bio; + bool is_poll = (iocb->ki_flags & IOCB_HIPRI) != 0; + bool is_read = (iov_iter_rw(iter) == READ), is_sync; + loff_t pos = iocb->ki_pos; + blk_qc_t qc = BLK_QC_T_NONE; + int ret = 0; + + if ((pos | iov_iter_alignment(iter)) & + (bdev_logical_block_size(bdev) - 1)) + return -EINVAL; + + bio = bio_alloc_kiocb(iocb, nr_pages, &blkdev_dio_pool); + + dio = container_of(bio, struct blkdev_dio, bio); + dio->is_sync = is_sync = is_sync_kiocb(iocb); + if (dio->is_sync) { + dio->waiter = current; + bio_get(bio); + } else { + dio->iocb = iocb; + } + + dio->size = 0; + dio->multi_bio = false; + dio->should_dirty = is_read && iter_is_iovec(iter); + + /* + * Don't plug for HIPRI/polled IO, as those should go straight + * to issue + */ + if (!is_poll) + blk_start_plug(&plug); + + for (;;) { + bio_set_dev(bio, bdev); + bio->bi_iter.bi_sector = pos >> 9; + bio->bi_write_hint = iocb->ki_hint; + bio->bi_private = dio; + bio->bi_end_io = blkdev_bio_end_io; + bio->bi_ioprio = iocb->ki_ioprio; + + ret = bio_iov_iter_get_pages(bio, iter); + if (unlikely(ret)) { + bio->bi_status = BLK_STS_IOERR; + bio_endio(bio); + break; + } + + if (is_read) { + bio->bi_opf = REQ_OP_READ; + if (dio->should_dirty) + bio_set_pages_dirty(bio); + } else { + bio->bi_opf = dio_bio_write_op(iocb); + task_io_account_write(bio->bi_iter.bi_size); + } + if (iocb->ki_flags & IOCB_NOWAIT) + bio->bi_opf |= REQ_NOWAIT; + + dio->size += bio->bi_iter.bi_size; + pos += bio->bi_iter.bi_size; + + nr_pages = bio_iov_vecs_to_alloc(iter, BIO_MAX_VECS); + if (!nr_pages) { + bool polled = false; + + if (iocb->ki_flags & IOCB_HIPRI) { + bio_set_polled(bio, iocb); + polled = true; + } + + qc = submit_bio(bio); + + if (polled) + WRITE_ONCE(iocb->ki_cookie, qc); + break; + } + + if (!dio->multi_bio) { + /* + * AIO needs an extra reference to ensure the dio + * structure which is embedded into the first bio + * stays around. + */ + if (!is_sync) + bio_get(bio); + dio->multi_bio = true; + atomic_set(&dio->ref, 2); + } else { + atomic_inc(&dio->ref); + } + + submit_bio(bio); + bio = bio_alloc(GFP_KERNEL, nr_pages); + } + + if (!is_poll) + blk_finish_plug(&plug); + + if (!is_sync) + return -EIOCBQUEUED; + + for (;;) { + set_current_state(TASK_UNINTERRUPTIBLE); + if (!READ_ONCE(dio->waiter)) + break; + + if (!(iocb->ki_flags & IOCB_HIPRI) || + !blk_poll(bdev_get_queue(bdev), qc, true)) + blk_io_schedule(); + } + __set_current_state(TASK_RUNNING); + + if (!ret) + ret = blk_status_to_errno(dio->bio.bi_status); + if (likely(!ret)) + ret = dio->size; + + bio_put(&dio->bio); + return ret; +} + +static ssize_t blkdev_direct_IO(struct kiocb *iocb, struct iov_iter *iter) +{ + unsigned int nr_pages; + + if (!iov_iter_count(iter)) + return 0; + + nr_pages = bio_iov_vecs_to_alloc(iter, BIO_MAX_VECS + 1); + if (is_sync_kiocb(iocb) && nr_pages <= BIO_MAX_VECS) + return __blkdev_direct_IO_simple(iocb, iter, nr_pages); + + return __blkdev_direct_IO(iocb, iter, bio_max_segs(nr_pages)); +} + +static int blkdev_writepage(struct page *page, struct writeback_control *wbc) +{ + return block_write_full_page(page, blkdev_get_block, wbc); +} + +static int blkdev_readpage(struct file * file, struct page * page) +{ + return block_read_full_page(page, blkdev_get_block); +} + +static void blkdev_readahead(struct readahead_control *rac) +{ + mpage_readahead(rac, blkdev_get_block); +} + +static int blkdev_write_begin(struct file *file, struct address_space *mapping, + loff_t pos, unsigned len, unsigned flags, struct page **pagep, + void **fsdata) +{ + return block_write_begin(mapping, pos, len, flags, pagep, + blkdev_get_block); +} + +static int blkdev_write_end(struct file *file, struct address_space *mapping, + loff_t pos, unsigned len, unsigned copied, struct page *page, + void *fsdata) +{ + int ret; + ret = block_write_end(file, mapping, pos, len, copied, page, fsdata); + + unlock_page(page); + put_page(page); + + return ret; +} + +static int blkdev_writepages(struct address_space *mapping, + struct writeback_control *wbc) +{ + return generic_writepages(mapping, wbc); +} + +const struct address_space_operations def_blk_aops = { + .set_page_dirty = __set_page_dirty_buffers, + .readpage = blkdev_readpage, + .readahead = blkdev_readahead, + .writepage = blkdev_writepage, + .write_begin = blkdev_write_begin, + .write_end = blkdev_write_end, + .writepages = blkdev_writepages, + .direct_IO = blkdev_direct_IO, + .migratepage = buffer_migrate_page_norefs, + .is_dirty_writeback = buffer_check_dirty_writeback, +}; + +/* + * for a block special file file_inode(file)->i_size is zero + * so we compute the size by hand (just as in block_read/write above) + */ +static loff_t blkdev_llseek(struct file *file, loff_t offset, int whence) +{ + struct inode *bd_inode = bdev_file_inode(file); + loff_t retval; + + inode_lock(bd_inode); + retval = fixed_size_llseek(file, offset, whence, i_size_read(bd_inode)); + inode_unlock(bd_inode); + return retval; +} + +static int blkdev_fsync(struct file *filp, loff_t start, loff_t end, + int datasync) +{ + struct inode *bd_inode = bdev_file_inode(filp); + struct block_device *bdev = I_BDEV(bd_inode); + int error; + + error = file_write_and_wait_range(filp, start, end); + if (error) + return error; + + /* + * There is no need to serialise calls to blkdev_issue_flush with + * i_mutex and doing so causes performance issues with concurrent + * O_SYNC writers to a block device. + */ + error = blkdev_issue_flush(bdev); + if (error == -EOPNOTSUPP) + error = 0; + + return error; +} + +static int blkdev_open(struct inode *inode, struct file *filp) +{ + struct block_device *bdev; + + /* + * Preserve backwards compatibility and allow large file access + * even if userspace doesn't ask for it explicitly. Some mkfs + * binary needs it. We might want to drop this workaround + * during an unstable branch. + */ + filp->f_flags |= O_LARGEFILE; + filp->f_mode |= FMODE_NOWAIT | FMODE_BUF_RASYNC; + + if (filp->f_flags & O_NDELAY) + filp->f_mode |= FMODE_NDELAY; + if (filp->f_flags & O_EXCL) + filp->f_mode |= FMODE_EXCL; + if ((filp->f_flags & O_ACCMODE) == 3) + filp->f_mode |= FMODE_WRITE_IOCTL; + + bdev = blkdev_get_by_dev(inode->i_rdev, filp->f_mode, filp); + if (IS_ERR(bdev)) + return PTR_ERR(bdev); + filp->f_mapping = bdev->bd_inode->i_mapping; + filp->f_wb_err = filemap_sample_wb_err(filp->f_mapping); + return 0; +} + +static int blkdev_close(struct inode *inode, struct file *filp) +{ + struct block_device *bdev = I_BDEV(bdev_file_inode(filp)); + + blkdev_put(bdev, filp->f_mode); + return 0; +} + +static long block_ioctl(struct file *file, unsigned cmd, unsigned long arg) +{ + struct block_device *bdev = I_BDEV(bdev_file_inode(file)); + fmode_t mode = file->f_mode; + + /* + * O_NDELAY can be altered using fcntl(.., F_SETFL, ..), so we have + * to updated it before every ioctl. + */ + if (file->f_flags & O_NDELAY) + mode |= FMODE_NDELAY; + else + mode &= ~FMODE_NDELAY; + + return blkdev_ioctl(bdev, mode, cmd, arg); +} + +/* + * Write data to the block device. Only intended for the block device itself + * and the raw driver which basically is a fake block device. + * + * Does not take i_mutex for the write and thus is not for general purpose + * use. + */ +static ssize_t blkdev_write_iter(struct kiocb *iocb, struct iov_iter *from) +{ + struct file *file = iocb->ki_filp; + struct inode *bd_inode = bdev_file_inode(file); + loff_t size = i_size_read(bd_inode); + struct blk_plug plug; + size_t shorted = 0; + ssize_t ret; + + if (bdev_read_only(I_BDEV(bd_inode))) + return -EPERM; + + if (IS_SWAPFILE(bd_inode) && !is_hibernate_resume_dev(bd_inode->i_rdev)) + return -ETXTBSY; + + if (!iov_iter_count(from)) + return 0; + + if (iocb->ki_pos >= size) + return -ENOSPC; + + if ((iocb->ki_flags & (IOCB_NOWAIT | IOCB_DIRECT)) == IOCB_NOWAIT) + return -EOPNOTSUPP; + + size -= iocb->ki_pos; + if (iov_iter_count(from) > size) { + shorted = iov_iter_count(from) - size; + iov_iter_truncate(from, size); + } + + blk_start_plug(&plug); + ret = __generic_file_write_iter(iocb, from); + if (ret > 0) + ret = generic_write_sync(iocb, ret); + iov_iter_reexpand(from, iov_iter_count(from) + shorted); + blk_finish_plug(&plug); + return ret; +} + +static ssize_t blkdev_read_iter(struct kiocb *iocb, struct iov_iter *to) +{ + struct file *file = iocb->ki_filp; + struct inode *bd_inode = bdev_file_inode(file); + loff_t size = i_size_read(bd_inode); + loff_t pos = iocb->ki_pos; + size_t shorted = 0; + ssize_t ret; + + if (pos >= size) + return 0; + + size -= pos; + if (iov_iter_count(to) > size) { + shorted = iov_iter_count(to) - size; + iov_iter_truncate(to, size); + } + + ret = generic_file_read_iter(iocb, to); + iov_iter_reexpand(to, iov_iter_count(to) + shorted); + return ret; +} + +#define BLKDEV_FALLOC_FL_SUPPORTED \ + (FALLOC_FL_KEEP_SIZE | FALLOC_FL_PUNCH_HOLE | \ + FALLOC_FL_ZERO_RANGE | FALLOC_FL_NO_HIDE_STALE) + +static long blkdev_fallocate(struct file *file, int mode, loff_t start, + loff_t len) +{ + struct block_device *bdev = I_BDEV(bdev_file_inode(file)); + loff_t end = start + len - 1; + loff_t isize; + int error; + + /* Fail if we don't recognize the flags. */ + if (mode & ~BLKDEV_FALLOC_FL_SUPPORTED) + return -EOPNOTSUPP; + + /* Don't go off the end of the device. */ + isize = i_size_read(bdev->bd_inode); + if (start >= isize) + return -EINVAL; + if (end >= isize) { + if (mode & FALLOC_FL_KEEP_SIZE) { + len = isize - start; + end = start + len - 1; + } else + return -EINVAL; + } + + /* + * Don't allow IO that isn't aligned to logical block size. + */ + if ((start | len) & (bdev_logical_block_size(bdev) - 1)) + return -EINVAL; + + /* Invalidate the page cache, including dirty pages. */ + error = truncate_bdev_range(bdev, file->f_mode, start, end); + if (error) + return error; + + switch (mode) { + case FALLOC_FL_ZERO_RANGE: + case FALLOC_FL_ZERO_RANGE | FALLOC_FL_KEEP_SIZE: + error = blkdev_issue_zeroout(bdev, start >> 9, len >> 9, + GFP_KERNEL, BLKDEV_ZERO_NOUNMAP); + break; + case FALLOC_FL_PUNCH_HOLE | FALLOC_FL_KEEP_SIZE: + error = blkdev_issue_zeroout(bdev, start >> 9, len >> 9, + GFP_KERNEL, BLKDEV_ZERO_NOFALLBACK); + break; + case FALLOC_FL_PUNCH_HOLE | FALLOC_FL_KEEP_SIZE | FALLOC_FL_NO_HIDE_STALE: + error = blkdev_issue_discard(bdev, start >> 9, len >> 9, + GFP_KERNEL, 0); + break; + default: + return -EOPNOTSUPP; + } + if (error) + return error; + + /* + * Invalidate the page cache again; if someone wandered in and dirtied + * a page, we just discard it - userspace has no way of knowing whether + * the write happened before or after discard completing... + */ + return truncate_bdev_range(bdev, file->f_mode, start, end); +} + +const struct file_operations def_blk_fops = { + .open = blkdev_open, + .release = blkdev_close, + .llseek = blkdev_llseek, + .read_iter = blkdev_read_iter, + .write_iter = blkdev_write_iter, + .iopoll = blkdev_iopoll, + .mmap = generic_file_mmap, + .fsync = blkdev_fsync, + .unlocked_ioctl = block_ioctl, +#ifdef CONFIG_COMPAT + .compat_ioctl = compat_blkdev_ioctl, +#endif + .splice_read = generic_file_splice_read, + .splice_write = iter_file_splice_write, + .fallocate = blkdev_fallocate, +}; + +static __init int blkdev_init(void) +{ + return bioset_init(&blkdev_dio_pool, 4, + offsetof(struct blkdev_dio, bio), + BIOSET_NEED_BVECS|BIOSET_PERCPU_CACHE); +} +module_init(blkdev_init); diff --git a/fs/block_dev.c b/fs/block_dev.c index 45df6cbccf12..84c97e276047 100644 --- a/fs/block_dev.c +++ b/fs/block_dev.c @@ -7,12 +7,10 @@ #include <linux/init.h> #include <linux/mm.h> -#include <linux/fcntl.h> #include <linux/slab.h> #include <linux/kmod.h> #include <linux/major.h> #include <linux/device_cgroup.h> -#include <linux/highmem.h> #include <linux/blkdev.h> #include <linux/backing-dev.h> #include <linux/module.h> @@ -20,20 +18,14 @@ #include <linux/magic.h> #include <linux/buffer_head.h> #include <linux/swap.h> -#include <linux/pagevec.h> #include <linux/writeback.h> -#include <linux/mpage.h> #include <linux/mount.h> #include <linux/pseudo_fs.h> #include <linux/uio.h> #include <linux/namei.h> -#include <linux/log2.h> #include <linux/cleancache.h> -#include <linux/task_io_accounting_ops.h> -#include <linux/falloc.h> #include <linux/part_stat.h> #include <linux/uaccess.h> -#include <linux/suspend.h> #include "internal.h" #include "../block/blk.h" @@ -42,8 +34,6 @@ struct bdev_inode { struct inode vfs_inode; }; -static const struct address_space_operations def_blk_aops; - static inline struct bdev_inode *BDEV_I(struct inode *inode) { return container_of(inode, struct bdev_inode, vfs_inode); @@ -194,332 +184,6 @@ int sb_min_blocksize(struct super_block *sb, int size) EXPORT_SYMBOL(sb_min_blocksize); -static int -blkdev_get_block(struct inode *inode, sector_t iblock, - struct buffer_head *bh, int create) -{ - bh->b_bdev = I_BDEV(inode); - bh->b_blocknr = iblock; - set_buffer_mapped(bh); - return 0; -} - -static struct inode *bdev_file_inode(struct file *file) -{ - return file->f_mapping->host; -} - -static unsigned int dio_bio_write_op(struct kiocb *iocb) -{ - unsigned int op = REQ_OP_WRITE | REQ_SYNC | REQ_IDLE; - - /* avoid the need for a I/O completion work item */ - if (iocb->ki_flags & IOCB_DSYNC) - op |= REQ_FUA; - return op; -} - -#define DIO_INLINE_BIO_VECS 4 - -static void blkdev_bio_end_io_simple(struct bio *bio) -{ - struct task_struct *waiter = bio->bi_private; - - WRITE_ONCE(bio->bi_private, NULL); - blk_wake_io_task(waiter); -} - -static ssize_t -__blkdev_direct_IO_simple(struct kiocb *iocb, struct iov_iter *iter, - unsigned int nr_pages) -{ - struct file *file = iocb->ki_filp; - struct block_device *bdev = I_BDEV(bdev_file_inode(file)); - struct bio_vec inline_vecs[DIO_INLINE_BIO_VECS], *vecs; - loff_t pos = iocb->ki_pos; - bool should_dirty = false; - struct bio bio; - ssize_t ret; - blk_qc_t qc; - - if ((pos | iov_iter_alignment(iter)) & - (bdev_logical_block_size(bdev) - 1)) - return -EINVAL; - - if (nr_pages <= DIO_INLINE_BIO_VECS) - vecs = inline_vecs; - else { - vecs = kmalloc_array(nr_pages, sizeof(struct bio_vec), - GFP_KERNEL); - if (!vecs) - return -ENOMEM; - } - - bio_init(&bio, vecs, nr_pages); - bio_set_dev(&bio, bdev); - bio.bi_iter.bi_sector = pos >> 9; - bio.bi_write_hint = iocb->ki_hint; - bio.bi_private = current; - bio.bi_end_io = blkdev_bio_end_io_simple; - bio.bi_ioprio = iocb->ki_ioprio; - - ret = bio_iov_iter_get_pages(&bio, iter); - if (unlikely(ret)) - goto out; - ret = bio.bi_iter.bi_size; - - if (iov_iter_rw(iter) == READ) { - bio.bi_opf = REQ_OP_READ; - if (iter_is_iovec(iter)) - should_dirty = true; - } else { - bio.bi_opf = dio_bio_write_op(iocb); - task_io_account_write(ret); - } - if (iocb->ki_flags & IOCB_NOWAIT) - bio.bi_opf |= REQ_NOWAIT; - if (iocb->ki_flags & IOCB_HIPRI) - bio_set_polled(&bio, iocb); - - qc = submit_bio(&bio); - for (;;) { - set_current_state(TASK_UNINTERRUPTIBLE); - if (!READ_ONCE(bio.bi_private)) - break; - if (!(iocb->ki_flags & IOCB_HIPRI) || - !blk_poll(bdev_get_queue(bdev), qc, true)) - blk_io_schedule(); - } - __set_current_state(TASK_RUNNING); - - bio_release_pages(&bio, should_dirty); - if (unlikely(bio.bi_status)) - ret = blk_status_to_errno(bio.bi_status); - -out: - if (vecs != inline_vecs) - kfree(vecs); - - bio_uninit(&bio); - - return ret; -} - -struct blkdev_dio { - union { - struct kiocb *iocb; - struct task_struct *waiter; - }; - size_t size; - atomic_t ref; - bool multi_bio : 1; - bool should_dirty : 1; - bool is_sync : 1; - struct bio bio; -}; - -static struct bio_set blkdev_dio_pool; - -static int blkdev_iopoll(struct kiocb *kiocb, bool wait) -{ - struct block_device *bdev = I_BDEV(kiocb->ki_filp->f_mapping->host); - struct request_queue *q = bdev_get_queue(bdev); - - return blk_poll(q, READ_ONCE(kiocb->ki_cookie), wait); -} - -static void blkdev_bio_end_io(struct bio *bio) -{ - struct blkdev_dio *dio = bio->bi_private; - bool should_dirty = dio->should_dirty; - - if (bio->bi_status && !dio->bio.bi_status) - dio->bio.bi_status = bio->bi_status; - - if (!dio->multi_bio || atomic_dec_and_test(&dio->ref)) { - if (!dio->is_sync) { - struct kiocb *iocb = dio->iocb; - ssize_t ret; - - if (likely(!dio->bio.bi_status)) { - ret = dio->size; - iocb->ki_pos += ret; - } else { - ret = blk_status_to_errno(dio->bio.bi_status); - } - - dio->iocb->ki_complete(iocb, ret, 0); - if (dio->multi_bio) - bio_put(&dio->bio); - } else { - struct task_struct *waiter = dio->waiter; - - WRITE_ONCE(dio->waiter, NULL); - blk_wake_io_task(waiter); - } - } - - if (should_dirty) { - bio_check_pages_dirty(bio); - } else { - bio_release_pages(bio, false); - bio_put(bio); - } -} - -static ssize_t __blkdev_direct_IO(struct kiocb *iocb, struct iov_iter *iter, - unsigned int nr_pages) -{ - struct file *file = iocb->ki_filp; - struct inode *inode = bdev_file_inode(file); - struct block_device *bdev = I_BDEV(inode); - struct blk_plug plug; - struct blkdev_dio *dio; - struct bio *bio; - bool is_poll = (iocb->ki_flags & IOCB_HIPRI) != 0; - bool is_read = (iov_iter_rw(iter) == READ), is_sync; - loff_t pos = iocb->ki_pos; - blk_qc_t qc = BLK_QC_T_NONE; - int ret = 0; - - if ((pos | iov_iter_alignment(iter)) & - (bdev_logical_block_size(bdev) - 1)) - return -EINVAL; - - bio = bio_alloc_kiocb(iocb, nr_pages, &blkdev_dio_pool); - - dio = container_of(bio, struct blkdev_dio, bio); - dio->is_sync = is_sync = is_sync_kiocb(iocb); - if (dio->is_sync) { - dio->waiter = current; - bio_get(bio); - } else { - dio->iocb = iocb; - } - - dio->size = 0; - dio->multi_bio = false; - dio->should_dirty = is_read && iter_is_iovec(iter); - - /* - * Don't plug for HIPRI/polled IO, as those should go straight - * to issue - */ - if (!is_poll) - blk_start_plug(&plug); - - for (;;) { - bio_set_dev(bio, bdev); - bio->bi_iter.bi_sector = pos >> 9; - bio->bi_write_hint = iocb->ki_hint; - bio->bi_private = dio; - bio->bi_end_io = blkdev_bio_end_io; - bio->bi_ioprio = iocb->ki_ioprio; - - ret = bio_iov_iter_get_pages(bio, iter); - if (unlikely(ret)) { - bio->bi_status = BLK_STS_IOERR; - bio_endio(bio); - break; - } - - if (is_read) { - bio->bi_opf = REQ_OP_READ; - if (dio->should_dirty) - bio_set_pages_dirty(bio); - } else { - bio->bi_opf = dio_bio_write_op(iocb); - task_io_account_write(bio->bi_iter.bi_size); - } - if (iocb->ki_flags & IOCB_NOWAIT) - bio->bi_opf |= REQ_NOWAIT; - - dio->size += bio->bi_iter.bi_size; - pos += bio->bi_iter.bi_size; - - nr_pages = bio_iov_vecs_to_alloc(iter, BIO_MAX_VECS); - if (!nr_pages) { - bool polled = false; - - if (iocb->ki_flags & IOCB_HIPRI) { - bio_set_polled(bio, iocb); - polled = true; - } - - qc = submit_bio(bio); - - if (polled) - WRITE_ONCE(iocb->ki_cookie, qc); - break; - } - - if (!dio->multi_bio) { - /* - * AIO needs an extra reference to ensure the dio - * structure which is embedded into the first bio - * stays around. - */ - if (!is_sync) - bio_get(bio); - dio->multi_bio = true; - atomic_set(&dio->ref, 2); - } else { - atomic_inc(&dio->ref); - } - - submit_bio(bio); - bio = bio_alloc(GFP_KERNEL, nr_pages); - } - - if (!is_poll) - blk_finish_plug(&plug); - - if (!is_sync) - return -EIOCBQUEUED; - - for (;;) { - set_current_state(TASK_UNINTERRUPTIBLE); - if (!READ_ONCE(dio->waiter)) - break; - - if (!(iocb->ki_flags & IOCB_HIPRI) || - !blk_poll(bdev_get_queue(bdev), qc, true)) - blk_io_schedule(); - } - __set_current_state(TASK_RUNNING); - - if (!ret) - ret = blk_status_to_errno(dio->bio.bi_status); - if (likely(!ret)) - ret = dio->size; - - bio_put(&dio->bio); - return ret; -} - -static ssize_t -blkdev_direct_IO(struct kiocb *iocb, struct iov_iter *iter) -{ - unsigned int nr_pages; - - if (!iov_iter_count(iter)) - return 0; - - nr_pages = bio_iov_vecs_to_alloc(iter, BIO_MAX_VECS + 1); - if (is_sync_kiocb(iocb) && nr_pages <= BIO_MAX_VECS) - return __blkdev_direct_IO_simple(iocb, iter, nr_pages); - - return __blkdev_direct_IO(iocb, iter, bio_max_segs(nr_pages)); -} - -static __init int blkdev_init(void) -{ - return bioset_init(&blkdev_dio_pool, 4, - offsetof(struct blkdev_dio, bio), - BIOSET_NEED_BVECS|BIOSET_PERCPU_CACHE); -} -module_init(blkdev_init); - int __sync_blockdev(struct block_device *bdev, int wait) { if (!bdev) @@ -637,81 +301,6 @@ out: } EXPORT_SYMBOL(thaw_bdev); -static int blkdev_writepage(struct page *page, struct writeback_control *wbc) -{ - return block_write_full_page(page, blkdev_get_block, wbc); -} - -static int blkdev_readpage(struct file * file, struct page * page) -{ - return block_read_full_page(page, blkdev_get_block); -} - -static void blkdev_readahead(struct readahead_control *rac) -{ - mpage_readahead(rac, blkdev_get_block); -} - -static int blkdev_write_begin(struct file *file, struct address_space *mapping, - loff_t pos, unsigned len, unsigned flags, - struct page **pagep, void **fsdata) -{ - return block_write_begin(mapping, pos, len, flags, pagep, - blkdev_get_block); -} - -static int blkdev_write_end(struct file *file, struct address_space *mapping, - loff_t pos, unsigned len, unsigned copied, - struct page *page, void *fsdata) -{ - int ret; - ret = block_write_end(file, mapping, pos, len, copied, page, fsdata); - - unlock_page(page); - put_page(page); - - return ret; -} - -/* - * private llseek: - * for a block special file file_inode(file)->i_size is zero - * so we compute the size by hand (just as in block_read/write above) - */ -static loff_t block_llseek(struct file *file, loff_t offset, int whence) -{ - struct inode *bd_inode = bdev_file_inode(file); - loff_t retval; - - inode_lock(bd_inode); - retval = fixed_size_llseek(file, offset, whence, i_size_read(bd_inode)); - inode_unlock(bd_inode); - return retval; -} - -static int blkdev_fsync(struct file *filp, loff_t start, loff_t end, - int datasync) -{ - struct inode *bd_inode = bdev_file_inode(filp); - struct block_device *bdev = I_BDEV(bd_inode); - int error; - - error = file_write_and_wait_range(filp, start, end); - if (error) - return error; - - /* - * There is no need to serialise calls to blkdev_issue_flush with - * i_mutex and doing so causes performance issues with concurrent - * O_SYNC writers to a block device. - */ - error = blkdev_issue_flush(bdev); - if (error == -EOPNOTSUPP) - error = 0; - - return error; -} - /** * bdev_read_page() - Start reading a page from a block device * @bdev: The device to read the page from @@ -1305,35 +894,6 @@ struct block_device *blkdev_get_by_path(const char *path, fmode_t mode, } EXPORT_SYMBOL(blkdev_get_by_path); -static int blkdev_open(struct inode * inode, struct file * filp) -{ - struct block_device *bdev; - - /* - * Preserve backwards compatibility and allow large file access - * even if userspace doesn't ask for it explicitly. Some mkfs - * binary needs it. We might want to drop this workaround - * during an unstable branch. - */ - filp->f_flags |= O_LARGEFILE; - - filp->f_mode |= FMODE_NOWAIT | FMODE_BUF_RASYNC; - - if (filp->f_flags & O_NDELAY) - filp->f_mode |= FMODE_NDELAY; - if (filp->f_flags & O_EXCL) - filp->f_mode |= FMODE_EXCL; - if ((filp->f_flags & O_ACCMODE) == 3) - filp->f_mode |= FMODE_WRITE_IOCTL; - - bdev = blkdev_get_by_dev(inode->i_rdev, filp->f_mode, filp); - if (IS_ERR(bdev)) - return PTR_ERR(bdev); - filp->f_mapping = bdev->bd_inode->i_mapping; - filp->f_wb_err = filemap_sample_wb_err(filp->f_mapping); - return 0; -} - void blkdev_put(struct block_device *bdev, fmode_t mode) { struct gendisk *disk = bdev->bd_disk; @@ -1397,203 +957,6 @@ void blkdev_put(struct block_device *bdev, fmode_t mode) } EXPORT_SYMBOL(blkdev_put); -static int blkdev_close(struct inode * inode, struct file * filp) -{ - struct block_device *bdev = I_BDEV(bdev_file_inode(filp)); - blkdev_put(bdev, filp->f_mode); - return 0; -} - -static long block_ioctl(struct file *file, unsigned cmd, unsigned long arg) -{ - struct block_device *bdev = I_BDEV(bdev_file_inode(file)); - fmode_t mode = file->f_mode; - - /* - * O_NDELAY can be altered using fcntl(.., F_SETFL, ..), so we have - * to updated it before every ioctl. - */ - if (file->f_flags & O_NDELAY) - mode |= FMODE_NDELAY; - else - mode &= ~FMODE_NDELAY; - - return blkdev_ioctl(bdev, mode, cmd, arg); -} - -/* - * Write data to the block device. Only intended for the block device itself - * and the raw driver which basically is a fake block device. - * - * Does not take i_mutex for the write and thus is not for general purpose - * use. - */ -static ssize_t blkdev_write_iter(struct kiocb *iocb, struct iov_iter *from) -{ - struct file *file = iocb->ki_filp; - struct inode *bd_inode = bdev_file_inode(file); - loff_t size = i_size_read(bd_inode); - struct blk_plug plug; - size_t shorted = 0; - ssize_t ret; - - if (bdev_read_only(I_BDEV(bd_inode))) - return -EPERM; - - if (IS_SWAPFILE(bd_inode) && !is_hibernate_resume_dev(bd_inode->i_rdev)) - return -ETXTBSY; - - if (!iov_iter_count(from)) - return 0; - - if (iocb->ki_pos >= size) - return -ENOSPC; - - if ((iocb->ki_flags & (IOCB_NOWAIT | IOCB_DIRECT)) == IOCB_NOWAIT) - return -EOPNOTSUPP; - - size -= iocb->ki_pos; - if (iov_iter_count(from) > size) { - shorted = iov_iter_count(from) - size; - iov_iter_truncate(from, size); - } - - blk_start_plug(&plug); - ret = __generic_file_write_iter(iocb, from); - if (ret > 0) - ret = generic_write_sync(iocb, ret); - iov_iter_reexpand(from, iov_iter_count(from) + shorted); - blk_finish_plug(&plug); - return ret; -} - -static ssize_t blkdev_read_iter(struct kiocb *iocb, struct iov_iter *to) -{ - struct file *file = iocb->ki_filp; - struct inode *bd_inode = bdev_file_inode(file); - loff_t size = i_size_read(bd_inode); - loff_t pos = iocb->ki_pos; - size_t shorted = 0; - ssize_t ret; - - if (pos >= size) - return 0; - - size -= pos; - if (iov_iter_count(to) > size) { - shorted = iov_iter_count(to) - size; - iov_iter_truncate(to, size); - } - - ret = generic_file_read_iter(iocb, to); - iov_iter_reexpand(to, iov_iter_count(to) + shorted); - return ret; -} - -static int blkdev_writepages(struct address_space *mapping, - struct writeback_control *wbc) -{ - return generic_writepages(mapping, wbc); -} - -static const struct address_space_operations def_blk_aops = { - .set_page_dirty = __set_page_dirty_buffers, - .readpage = blkdev_readpage, - .readahead = blkdev_readahead, - .writepage = blkdev_writepage, - .write_begin = blkdev_write_begin, - .write_end = blkdev_write_end, - .writepages = blkdev_writepages, - .direct_IO = blkdev_direct_IO, - .migratepage = buffer_migrate_page_norefs, - .is_dirty_writeback = buffer_check_dirty_writeback, -}; - -#define BLKDEV_FALLOC_FL_SUPPORTED \ - (FALLOC_FL_KEEP_SIZE | FALLOC_FL_PUNCH_HOLE | \ - FALLOC_FL_ZERO_RANGE | FALLOC_FL_NO_HIDE_STALE) - -static long blkdev_fallocate(struct file *file, int mode, loff_t start, - loff_t len) -{ - struct block_device *bdev = I_BDEV(bdev_file_inode(file)); - loff_t end = start + len - 1; - loff_t isize; - int error; - - /* Fail if we don't recognize the flags. */ - if (mode & ~BLKDEV_FALLOC_FL_SUPPORTED) - return -EOPNOTSUPP; - - /* Don't go off the end of the device. */ - isize = i_size_read(bdev->bd_inode); - if (start >= isize) - return -EINVAL; - if (end >= isize) { - if (mode & FALLOC_FL_KEEP_SIZE) { - len = isize - start; - end = start + len - 1; - } else - return -EINVAL; - } - - /* - * Don't allow IO that isn't aligned to logical block size. - */ - if ((start | len) & (bdev_logical_block_size(bdev) - 1)) - return -EINVAL; - - /* Invalidate the page cache, including dirty pages. */ - error = truncate_bdev_range(bdev, file->f_mode, start, end); - if (error) - return error; - - switch (mode) { - case FALLOC_FL_ZERO_RANGE: - case FALLOC_FL_ZERO_RANGE | FALLOC_FL_KEEP_SIZE: - error = blkdev_issue_zeroout(bdev, start >> 9, len >> 9, - GFP_KERNEL, BLKDEV_ZERO_NOUNMAP); - break; - case FALLOC_FL_PUNCH_HOLE | FALLOC_FL_KEEP_SIZE: - error = blkdev_issue_zeroout(bdev, start >> 9, len >> 9, - GFP_KERNEL, BLKDEV_ZERO_NOFALLBACK); - break; - case FALLOC_FL_PUNCH_HOLE | FALLOC_FL_KEEP_SIZE | FALLOC_FL_NO_HIDE_STALE: - error = blkdev_issue_discard(bdev, start >> 9, len >> 9, - GFP_KERNEL, 0); - break; - default: - return -EOPNOTSUPP; - } - if (error) - return error; - - /* - * Invalidate the page cache again; if someone wandered in and dirtied - * a page, we just discard it - userspace has no way of knowing whether - * the write happened before or after discard completing... - */ - return truncate_bdev_range(bdev, file->f_mode, start, end); -} - -const struct file_operations def_blk_fops = { - .open = blkdev_open, - .release = blkdev_close, - .llseek = block_llseek, - .read_iter = blkdev_read_iter, - .write_iter = blkdev_write_iter, - .iopoll = blkdev_iopoll, - .mmap = generic_file_mmap, - .fsync = blkdev_fsync, - .unlocked_ioctl = block_ioctl, -#ifdef CONFIG_COMPAT - .compat_ioctl = compat_blkdev_ioctl, -#endif - .splice_read = generic_file_splice_read, - .splice_write = iter_file_splice_write, - .fallocate = blkdev_fallocate, -}; - /** * lookup_bdev - lookup a struct block_device by name * @pathname: special file representing the block device |