From: Goldwyn Rodrigues <rgoldwyn@xxxxxxxx>
This is the main patch to switch call from
__blockdev_direct_IO() to iomap_dio_rw(). In this patch:
Removed buffer_head references
Removed inode_dio_begin() and inode_dio_end() functions since
they are called in iomap_dio_rw().
Renamed btrfs_get_blocks_direct() to direct_iomap_begin() and
used it as iomap_begin()
address_space.direct_IO now is a noop since direct_IO is called
from __btrfs_write_direct().
Removed flags parameter used for __blockdev_direct_IO(). iomap is
capable of direct I/O reads from a hole, so we don't need to
return -ENOENT.
Signed-off-by: Goldwyn Rodrigues <rgoldwyn@xxxxxxxx>
---
fs/btrfs/ctree.h | 1 +
fs/btrfs/file.c | 2 +-
fs/btrfs/inode.c | 105 ++++++++++++++++++-------------------------------------
3 files changed, 36 insertions(+), 72 deletions(-)
diff --git a/fs/btrfs/ctree.h b/fs/btrfs/ctree.h
index fe2b8765d9e6..cde8423673fc 100644
--- a/fs/btrfs/ctree.h
+++ b/fs/btrfs/ctree.h
@@ -2903,6 +2903,7 @@ int btrfs_writepage_cow_fixup(struct page *page, u64 start, u64 end);
void btrfs_writepage_endio_finish_ordered(struct page *page, u64 start,
u64 end, int uptodate);
extern const struct dentry_operations btrfs_dentry_operations;
+ssize_t btrfs_direct_IO(struct kiocb *iocb, struct iov_iter *iter);
/* ioctl.c */
long btrfs_ioctl(struct file *file, unsigned int cmd, unsigned long arg);
diff --git a/fs/btrfs/file.c b/fs/btrfs/file.c
index eede9dcbb4b6..d47da00fa61e 100644
--- a/fs/btrfs/file.c
+++ b/fs/btrfs/file.c
@@ -1835,7 +1835,7 @@ static ssize_t __btrfs_direct_write(struct kiocb *iocb, struct iov_iter *from)
loff_t endbyte;
int err;
- written = generic_file_direct_write(iocb, from);
+ written = btrfs_direct_IO(iocb, from);
if (written < 0 || !iov_iter_count(from))
return written;
diff --git a/fs/btrfs/inode.c b/fs/btrfs/inode.c
index c6dc4dd16cf7..e2e4dfb7a568 100644
--- a/fs/btrfs/inode.c
+++ b/fs/btrfs/inode.c
@@ -8,6 +8,7 @@
#include <linux/buffer_head.h>
#include <linux/file.h>
#include <linux/fs.h>
+#include <linux/iomap.h>
#include <linux/pagemap.h>
#include <linux/highmem.h>
#include <linux/time.h>
@@ -7619,28 +7620,7 @@ static struct extent_map *create_io_em(struct inode *inode, u64 start, u64 len,
}
-static int btrfs_get_blocks_direct_read(struct extent_map *em,
- struct buffer_head *bh_result,
- struct inode *inode,
- u64 start, u64 len)
-{
- if (em->block_start == EXTENT_MAP_HOLE ||
- test_bit(EXTENT_FLAG_PREALLOC, &em->flags))
- return -ENOENT;
-
- len = min(len, em->len - (start - em->start));
-
- bh_result->b_blocknr = (em->block_start + (start - em->start)) >>
- inode->i_blkbits;
- bh_result->b_size = len;
- bh_result->b_bdev = em->bdev;
- set_buffer_mapped(bh_result);
-
- return 0;
-}
-
static int btrfs_get_blocks_direct_write(struct extent_map **map,
- struct buffer_head *bh_result,
struct inode *inode,
struct btrfs_dio_data *dio_data,
u64 start, u64 len)
@@ -7702,7 +7682,6 @@ static int btrfs_get_blocks_direct_write(struct extent_map **map,
}
/* this will cow the extent */
- len = bh_result->b_size;
free_extent_map(em);
*map = em = btrfs_new_extent_direct(inode, start, len);
if (IS_ERR(em)) {
@@ -7713,15 +7692,6 @@ static int btrfs_get_blocks_direct_write(struct extent_map **map,
len = min(len, em->len - (start - em->start));
skip_cow:
- bh_result->b_blocknr = (em->block_start + (start - em->start)) >>
- inode->i_blkbits;
- bh_result->b_size = len;
- bh_result->b_bdev = em->bdev;
- set_buffer_mapped(bh_result);
-
- if (!test_bit(EXTENT_FLAG_PREALLOC, &em->flags))
- set_buffer_new(bh_result);
-
/*
* Need to update the i_size under the extent lock so buffered
* readers will get the updated i_size when we unlock.
@@ -7737,17 +7707,18 @@ static int btrfs_get_blocks_direct_write(struct extent_map **map,
return ret;
}
-static int btrfs_get_blocks_direct(struct inode *inode, sector_t iblock,
- struct buffer_head *bh_result, int create)
+static int direct_iomap_begin(struct inode *inode, loff_t start,
+ loff_t length, unsigned flags, struct iomap *iomap,
+ struct iomap *srcmap)
{
struct btrfs_fs_info *fs_info = btrfs_sb(inode->i_sb);
struct extent_map *em;
struct extent_state *cached_state = NULL;
struct btrfs_dio_data *dio_data = NULL;
- u64 start = iblock << inode->i_blkbits;
u64 lockstart, lockend;
- u64 len = bh_result->b_size;
+ int create = flags & IOMAP_WRITE;
int ret = 0;
+ u64 len = length;
if (!create)
len = min_t(u64, len, fs_info->sectorsize);
@@ -7803,7 +7774,7 @@ static int btrfs_get_blocks_direct(struct inode *inode, sector_t iblock,
}
if (create) {
- ret = btrfs_get_blocks_direct_write(&em, bh_result, inode,
+ ret = btrfs_get_blocks_direct_write(&em, inode,
dio_data, start, len);
if (ret < 0)
goto unlock_err;
@@ -7811,19 +7782,13 @@ static int btrfs_get_blocks_direct(struct inode *inode, sector_t iblock,
unlock_extent_cached(&BTRFS_I(inode)->io_tree, lockstart,
lockend, &cached_state);
} else {
- ret = btrfs_get_blocks_direct_read(em, bh_result, inode,
- start, len);
- /* Can be negative only if we read from a hole */
- if (ret < 0) {
- ret = 0;
- free_extent_map(em);
- goto unlock_err;
- }
+
+ len = min(len, em->len - (start - em->start));
/*
* We need to unlock only the end area that we aren't using.
* The rest is going to be unlocked by the endio routine.
*/
- lockstart = start + bh_result->b_size;
+ lockstart = start + len;
if (lockstart < lockend) {
unlock_extent_cached(&BTRFS_I(inode)->io_tree,
lockstart, lockend, &cached_state);
@@ -7832,6 +7797,18 @@ static int btrfs_get_blocks_direct(struct inode *inode, sector_t iblock,
}
}
+ if ((em->block_start == EXTENT_MAP_HOLE) ||
+ (test_bit(EXTENT_FLAG_PREALLOC, &em->flags) && !create)) {
+ iomap->addr = IOMAP_NULL_ADDR;
+ iomap->type = IOMAP_HOLE;
+ } else {
+ iomap->addr = em->block_start - (start - em->start);
+ iomap->type = IOMAP_MAPPED;
+ }
+ iomap->offset = start;
+ iomap->bdev = em->bdev;
+ iomap->length = min(len, em->len - (start - em->start));
+
free_extent_map(em);
return 0;
@@ -8199,9 +8176,8 @@ static void btrfs_endio_direct_read(struct bio *bio)
kfree(dip);
dio_bio->bi_status = err;
- dio_end_io(dio_bio);
+ bio_endio(dio_bio);
btrfs_io_bio_free_csum(io_bio);
- bio_put(bio);
}
static void __endio_write_update_ordered(struct inode *inode,
@@ -8263,8 +8239,7 @@ static void btrfs_endio_direct_write(struct bio *bio)
kfree(dip);
dio_bio->bi_status = bio->bi_status;
- dio_end_io(dio_bio);
- bio_put(bio);
+ bio_endio(dio_bio);
}
static blk_status_t btrfs_submit_bio_start_direct_io(void *private_data,
@@ -8568,7 +8543,7 @@ static void btrfs_submit_direct(struct bio *dio_bio, struct inode *inode,
/*
* The end io callbacks free our dip, do the final put on bio
* and all the cleanup and final put for dio_bio (through
- * dio_end_io()).
+ * end_io()).
*/
dip = NULL;
bio = NULL;
@@ -8587,7 +8562,7 @@ static void btrfs_submit_direct(struct bio *dio_bio, struct inode *inode,
* Releases and cleans up our dio_bio, no need to bio_put()
* nor bio_endio()/bio_io_error() against dio_bio.
*/
- dio_end_io(dio_bio);
+ bio_endio(dio_bio);
}
if (bio)
bio_put(bio);
@@ -8627,7 +8602,11 @@ static ssize_t check_direct_IO(struct btrfs_fs_info *fs_info,
return retval;
}
-static ssize_t btrfs_direct_IO(struct kiocb *iocb, struct iov_iter *iter)
+static const struct iomap_ops dio_iomap_ops = {
+ .iomap_begin = direct_iomap_begin,
+};
+
+ssize_t btrfs_direct_IO(struct kiocb *iocb, struct iov_iter *iter)
{
struct file *file = iocb->ki_filp;
struct inode *inode = file->f_mapping->host;
@@ -8637,14 +8616,11 @@ static ssize_t btrfs_direct_IO(struct kiocb *iocb, struct iov_iter *iter)
loff_t offset = iocb->ki_pos;
size_t count = 0;
int flags = 0;
- bool wakeup = true;
- bool relock = false;
ssize_t ret;
if (check_direct_IO(fs_info, iter, offset))
return 0;
- inode_dio_begin(inode);
/*
* The generic stuff only does filemap_write_and_wait_range, which
@@ -8664,11 +8640,7 @@ static ssize_t btrfs_direct_IO(struct kiocb *iocb, struct iov_iter *iter)
* the isize, but it is protected by i_mutex. So we can
* not unlock the i_mutex at this case.
*/
- if (offset + count <= inode->i_size) {
- dio_data.overwrite = 1;
- inode_unlock(inode);
- relock = true;
- } else if (iocb->ki_flags & IOCB_NOWAIT) {
+ if (iocb->ki_flags & IOCB_NOWAIT) {
ret = -EAGAIN;
goto out;
}
@@ -8690,15 +8662,11 @@ static ssize_t btrfs_direct_IO(struct kiocb *iocb, struct iov_iter *iter)
down_read(&BTRFS_I(inode)->dio_sem);
} else if (test_bit(BTRFS_INODE_READDIO_NEED_LOCK,
&BTRFS_I(inode)->runtime_flags)) {
- inode_dio_end(inode);
flags = DIO_LOCKING | DIO_SKIP_HOLES;
- wakeup = false;
}
- ret = __blockdev_direct_IO(iocb, inode,
- fs_info->fs_devices->latest_bdev,
- iter, btrfs_get_blocks_direct, NULL,
- btrfs_submit_direct, flags);
+ ret = iomap_dio_rw(iocb, iter, &dio_iomap_ops, NULL, is_sync_kiocb(iocb));
+
if (iov_iter_rw(iter) == WRITE) {
up_read(&BTRFS_I(inode)->dio_sem);
current->journal_info = NULL;
@@ -8725,11 +8693,6 @@ static ssize_t btrfs_direct_IO(struct kiocb *iocb, struct iov_iter *iter)
btrfs_delalloc_release_extents(BTRFS_I(inode), count);
}
out:
- if (wakeup)
- inode_dio_end(inode);
- if (relock)
- inode_lock(inode);
-
extent_changeset_free(data_reserved);
return ret;
}
--
2.16.4
