[PATCH 10/11] xfs: use the iomap write page code

From: Christoph Hellwig
Date: Tue Oct 01 2019 - 03:16:44 EST

Use the new iomap writeback code that was copied from XFS to perform
writeback.

Signed-off-by: Christoph Hellwig <hch@xxxxxx>
[darrick: reduce this patch only to convert the xfs writeback code]
Signed-off-by: Darrick J. Wong <darrick.wong@xxxxxxxxxx>
---
fs/xfs/xfs_aops.c | 667 +++++----------------------------------------
fs/xfs/xfs_aops.h | 17 --
fs/xfs/xfs_super.c | 11 +-
fs/xfs/xfs_trace.h | 39 ---
4 files changed, 74 insertions(+), 660 deletions(-)

diff --git a/fs/xfs/xfs_aops.c b/fs/xfs/xfs_aops.c
index 8c101081e3b1..d0a25b822123 100644
--- a/fs/xfs/xfs_aops.c
+++ b/fs/xfs/xfs_aops.c
@@ -18,16 +18,18 @@
#include "xfs_bmap_util.h"
#include "xfs_reflink.h"

-/*
- * structure owned by writepages passed to individual writepage calls
- */
struct xfs_writepage_ctx {
- struct iomap iomap;
+ struct iomap_writepage_ctx ctx;
unsigned int data_seq;
unsigned int cow_seq;
- struct xfs_ioend *ioend;
};

+static inline struct xfs_writepage_ctx *
+XFS_WPC(struct iomap_writepage_ctx *ctx)
+{
+ return container_of(ctx, struct xfs_writepage_ctx, ctx);
+}
+
struct block_device *
xfs_find_bdev_for_inode(
struct inode *inode)
@@ -54,71 +56,10 @@ xfs_find_daxdev_for_inode(
return mp->m_ddev_targp->bt_daxdev;
}

-static void
-xfs_finish_page_writeback(
- struct inode *inode,
- struct bio_vec *bvec,
- int error)
-{
- struct iomap_page *iop = to_iomap_page(bvec->bv_page);
-
- if (error) {
- SetPageError(bvec->bv_page);
- mapping_set_error(inode->i_mapping, -EIO);
- }
-
- ASSERT(iop || i_blocksize(inode) == PAGE_SIZE);
- ASSERT(!iop || atomic_read(&iop->write_count) > 0);
-
- if (!iop || atomic_dec_and_test(&iop->write_count))
- end_page_writeback(bvec->bv_page);
-}
-
-/*
- * We're now finished for good with this ioend structure. Update the page
- * state, release holds on bios, and finally free up memory. Do not use the
- * ioend after this.
- */
-STATIC void
-xfs_destroy_ioend(
- struct xfs_ioend *ioend,
- int error)
-{
- struct inode *inode = ioend->io_inode;
- struct bio *bio = &ioend->io_inline_bio;
- struct bio *last = ioend->io_bio, *next;
- u64 start = bio->bi_iter.bi_sector;
- bool quiet = bio_flagged(bio, BIO_QUIET);
-
- for (bio = &ioend->io_inline_bio; bio; bio = next) {
- struct bio_vec *bvec;
- struct bvec_iter_all iter_all;
-
- /*
- * For the last bio, bi_private points to the ioend, so we
- * need to explicitly end the iteration here.
- */
- if (bio == last)
- next = NULL;
- else
- next = bio->bi_private;
-
- /* walk each page on bio, ending page IO on them */
- bio_for_each_segment_all(bvec, bio, iter_all)
- xfs_finish_page_writeback(inode, bvec, error);
- bio_put(bio);
- }
-
- if (unlikely(error && !quiet)) {
- xfs_err_ratelimited(XFS_I(inode)->i_mount,
- "writeback error on sector %llu", start);
- }
-}
-
/*
* Fast and loose check if this write could update the on-disk inode size.
*/
-static inline bool xfs_ioend_is_append(struct xfs_ioend *ioend)
+static inline bool xfs_ioend_is_append(struct iomap_ioend *ioend)
{
return ioend->io_offset + ioend->io_size >
XFS_I(ioend->io_inode)->i_d.di_size;
@@ -126,7 +67,7 @@ static inline bool xfs_ioend_is_append(struct xfs_ioend *ioend)

STATIC int
xfs_setfilesize_trans_alloc(
- struct xfs_ioend *ioend)
+ struct iomap_ioend *ioend)
{
struct xfs_mount *mp = XFS_I(ioend->io_inode)->i_mount;
struct xfs_trans *tp;
@@ -136,7 +77,7 @@ xfs_setfilesize_trans_alloc(
if (error)
return error;

- ioend->io_append_trans = tp;
+ ioend->io_private = tp;

/*
* We may pass freeze protection with a transaction. So tell lockdep
@@ -199,11 +140,11 @@ xfs_setfilesize(

STATIC int
xfs_setfilesize_ioend(
- struct xfs_ioend *ioend,
+ struct iomap_ioend *ioend,
int error)
{
struct xfs_inode *ip = XFS_I(ioend->io_inode);
- struct xfs_trans *tp = ioend->io_append_trans;
+ struct xfs_trans *tp = ioend->io_private;

/*
* The transaction may have been allocated in the I/O submission thread,
@@ -227,9 +168,8 @@ xfs_setfilesize_ioend(
*/
STATIC void
xfs_end_ioend(
- struct xfs_ioend *ioend)
+ struct iomap_ioend *ioend)
{
- struct list_head ioend_list;
struct xfs_inode *ip = XFS_I(ioend->io_inode);
xfs_off_t offset = ioend->io_offset;
size_t size = ioend->io_size;
@@ -269,45 +209,15 @@ xfs_end_ioend(
else if (ioend->io_type == IOMAP_UNWRITTEN)
error = xfs_iomap_write_unwritten(ip, offset, size, false);
else
- ASSERT(!xfs_ioend_is_append(ioend) || ioend->io_append_trans);
+ ASSERT(!xfs_ioend_is_append(ioend) || ioend->io_private);

done:
- if (ioend->io_append_trans)
+ if (ioend->io_private)
error = xfs_setfilesize_ioend(ioend, error);
- list_replace_init(&ioend->io_list, &ioend_list);
- xfs_destroy_ioend(ioend, error);
-
- while (!list_empty(&ioend_list)) {
- ioend = list_first_entry(&ioend_list, struct xfs_ioend,
- io_list);
- list_del_init(&ioend->io_list);
- xfs_destroy_ioend(ioend, error);
- }
-
+ iomap_finish_ioends(ioend, error);
memalloc_nofs_restore(nofs_flag);
}

-/*
- * We can merge two adjacent ioends if they have the same set of work to do.
- */
-static bool
-xfs_ioend_can_merge(
- struct xfs_ioend *ioend,
- struct xfs_ioend *next)
-{
- if (ioend->io_bio->bi_status != next->io_bio->bi_status)
- return false;
- if ((ioend->io_flags & IOMAP_F_SHARED) ^
- (next->io_flags & IOMAP_F_SHARED))
- return false;
- if ((ioend->io_type == IOMAP_UNWRITTEN) ^
- (next->io_type == IOMAP_UNWRITTEN))
- return false;
- if (ioend->io_offset + ioend->io_size != next->io_offset)
- return false;
- return true;
-}
-
/*
* If the to be merged ioend has a preallocated transaction for file
* size updates we need to ensure the ioend it is merged into also
@@ -315,80 +225,38 @@ xfs_ioend_can_merge(
* as it is guaranteed to be clean.
*/
static void
-xfs_ioend_merge_append_transactions(
- struct xfs_ioend *ioend,
- struct xfs_ioend *next)
+xfs_ioend_merge_private(
+ struct iomap_ioend *ioend,
+ struct iomap_ioend *next)
{
- if (!ioend->io_append_trans) {
- ioend->io_append_trans = next->io_append_trans;
- next->io_append_trans = NULL;
+ if (!ioend->io_private) {
+ ioend->io_private = next->io_private;
+ next->io_private = NULL;
} else {
xfs_setfilesize_ioend(next, -ECANCELED);
}
}

-/* Try to merge adjacent completions. */
-STATIC void
-xfs_ioend_try_merge(
- struct xfs_ioend *ioend,
- struct list_head *more_ioends)
-{
- struct xfs_ioend *next_ioend;
-
- while (!list_empty(more_ioends)) {
- next_ioend = list_first_entry(more_ioends, struct xfs_ioend,
- io_list);
- if (!xfs_ioend_can_merge(ioend, next_ioend))
- break;
- list_move_tail(&next_ioend->io_list, &ioend->io_list);
- ioend->io_size += next_ioend->io_size;
- if (next_ioend->io_append_trans)
- xfs_ioend_merge_append_transactions(ioend, next_ioend);
- }
-}
-
-/* list_sort compare function for ioends */
-static int
-xfs_ioend_compare(
- void *priv,
- struct list_head *a,
- struct list_head *b)
-{
- struct xfs_ioend *ia;
- struct xfs_ioend *ib;
-
- ia = container_of(a, struct xfs_ioend, io_list);
- ib = container_of(b, struct xfs_ioend, io_list);
- if (ia->io_offset < ib->io_offset)
- return -1;
- else if (ia->io_offset > ib->io_offset)
- return 1;
- return 0;
-}
-
/* Finish all pending io completions. */
void
xfs_end_io(
struct work_struct *work)
{
- struct xfs_inode *ip;
- struct xfs_ioend *ioend;
- struct list_head completion_list;
+ struct xfs_inode *ip =
+ container_of(work, struct xfs_inode, i_ioend_work);
+ struct iomap_ioend *ioend;
+ struct list_head tmp;
unsigned long flags;

- ip = container_of(work, struct xfs_inode, i_ioend_work);
-
spin_lock_irqsave(&ip->i_ioend_lock, flags);
- list_replace_init(&ip->i_ioend_list, &completion_list);
+ list_replace_init(&ip->i_ioend_list, &tmp);
spin_unlock_irqrestore(&ip->i_ioend_lock, flags);

- list_sort(NULL, &completion_list, xfs_ioend_compare);
-
- while (!list_empty(&completion_list)) {
- ioend = list_first_entry(&completion_list, struct xfs_ioend,
- io_list);
+ iomap_sort_ioends(&tmp);
+ while (!list_empty(&tmp)) {
+ ioend = list_first_entry(&tmp, struct iomap_ioend, io_list);
list_del_init(&ioend->io_list);
- xfs_ioend_try_merge(ioend, &completion_list);
+ iomap_ioend_try_merge(ioend, &tmp, xfs_ioend_merge_private);
xfs_end_ioend(ioend);
}
}
@@ -397,22 +265,16 @@ STATIC void
xfs_end_bio(
struct bio *bio)
{
- struct xfs_ioend *ioend = bio->bi_private;
+ struct iomap_ioend *ioend = bio->bi_private;
struct xfs_inode *ip = XFS_I(ioend->io_inode);
- struct xfs_mount *mp = ip->i_mount;
unsigned long flags;

- if ((ioend->io_flags & IOMAP_F_SHARED) ||
- ioend->io_type == IOMAP_UNWRITTEN ||
- ioend->io_append_trans != NULL) {
- spin_lock_irqsave(&ip->i_ioend_lock, flags);
- if (list_empty(&ip->i_ioend_list))
- WARN_ON_ONCE(!queue_work(mp->m_unwritten_workqueue,
- &ip->i_ioend_work));
- list_add_tail(&ioend->io_list, &ip->i_ioend_list);
- spin_unlock_irqrestore(&ip->i_ioend_lock, flags);
- } else
- xfs_destroy_ioend(ioend, blk_status_to_errno(bio->bi_status));
+ spin_lock_irqsave(&ip->i_ioend_lock, flags);
+ if (list_empty(&ip->i_ioend_list))
+ WARN_ON_ONCE(!queue_work(ip->i_mount->m_unwritten_workqueue,
+ &ip->i_ioend_work));
+ list_add_tail(&ioend->io_list, &ip->i_ioend_list);
+ spin_unlock_irqrestore(&ip->i_ioend_lock, flags);
}

/*
@@ -421,7 +283,7 @@ xfs_end_bio(
*/
static bool
xfs_imap_valid(
- struct xfs_writepage_ctx *wpc,
+ struct iomap_writepage_ctx *wpc,
struct xfs_inode *ip,
loff_t offset)
{
@@ -443,10 +305,10 @@ xfs_imap_valid(
* checked (and found nothing at this offset) could have added
* overlapping blocks.
*/
- if (wpc->data_seq != READ_ONCE(ip->i_df.if_seq))
+ if (XFS_WPC(wpc)->data_seq != READ_ONCE(ip->i_df.if_seq))
return false;
if (xfs_inode_has_cow_data(ip) &&
- wpc->cow_seq != READ_ONCE(ip->i_cowfp->if_seq))
+ XFS_WPC(wpc)->cow_seq != READ_ONCE(ip->i_cowfp->if_seq))
return false;
return true;
}
@@ -461,12 +323,18 @@ xfs_imap_valid(
*/
static int
xfs_convert_blocks(
- struct xfs_writepage_ctx *wpc,
+ struct iomap_writepage_ctx *wpc,
struct xfs_inode *ip,
int whichfork,
loff_t offset)
{
int error;
+ unsigned *seq;
+
+ if (whichfork == XFS_COW_FORK)
+ seq = &XFS_WPC(wpc)->cow_seq;
+ else
+ seq = &XFS_WPC(wpc)->data_seq;

/*
* Attempt to allocate whatever delalloc extent currently backs offset
@@ -476,8 +344,7 @@ xfs_convert_blocks(
*/
do {
error = xfs_bmapi_convert_delalloc(ip, whichfork, offset,
- &wpc->iomap, whichfork == XFS_COW_FORK ?
- &wpc->cow_seq : &wpc->data_seq);
+ &wpc->iomap, seq);
if (error)
return error;
} while (wpc->iomap.offset + wpc->iomap.length <= offset);
@@ -485,9 +352,9 @@ xfs_convert_blocks(
return 0;
}

-STATIC int
+static int
xfs_map_blocks(
- struct xfs_writepage_ctx *wpc,
+ struct iomap_writepage_ctx *wpc,
struct inode *inode,
loff_t offset)
{
@@ -543,7 +410,7 @@ xfs_map_blocks(
xfs_iext_lookup_extent(ip, ip->i_cowfp, offset_fsb, &icur, &imap))
cow_fsb = imap.br_startoff;
if (cow_fsb != NULLFILEOFF && cow_fsb <= offset_fsb) {
- wpc->cow_seq = READ_ONCE(ip->i_cowfp->if_seq);
+ XFS_WPC(wpc)->cow_seq = READ_ONCE(ip->i_cowfp->if_seq);
xfs_iunlock(ip, XFS_ILOCK_SHARED);

whichfork = XFS_COW_FORK;
@@ -566,7 +433,7 @@ xfs_map_blocks(
*/
if (!xfs_iext_lookup_extent(ip, &ip->i_df, offset_fsb, &icur, &imap))
imap.br_startoff = end_fsb; /* fake a hole past EOF */
- wpc->data_seq = READ_ONCE(ip->i_df.if_seq);
+ XFS_WPC(wpc)->data_seq = READ_ONCE(ip->i_df.if_seq);
xfs_iunlock(ip, XFS_ILOCK_SHARED);

/* landed in a hole or beyond EOF? */
@@ -630,24 +497,9 @@ xfs_map_blocks(
return 0;
}

-/*
- * Submit the bio for an ioend. We are passed an ioend with a bio attached to
- * it, and we submit that bio. The ioend may be used for multiple bio
- * submissions, so we only want to allocate an append transaction for the ioend
- * once. In the case of multiple bio submission, each bio will take an IO
- * reference to the ioend to ensure that the ioend completion is only done once
- * all bios have been submitted and the ioend is really done.
- *
- * If @status is non-zero, it means that we have a situation where some part of
- * the submission process has failed after we have marked paged for writeback
- * and unlocked them. In this situation, we need to fail the bio and ioend
- * rather than submit it to IO. This typically only happens on a filesystem
- * shutdown.
- */
-STATIC int
+static int
xfs_submit_ioend(
- struct writeback_control *wbc,
- struct xfs_ioend *ioend,
+ struct iomap_ioend *ioend,
int status)
{
unsigned int nofs_flag;
@@ -670,139 +522,15 @@ xfs_submit_ioend(
((ioend->io_flags & IOMAP_F_SHARED) ||
ioend->io_type != IOMAP_UNWRITTEN) &&
xfs_ioend_is_append(ioend) &&
- !ioend->io_append_trans)
+ !ioend->io_private)
status = xfs_setfilesize_trans_alloc(ioend);

memalloc_nofs_restore(nofs_flag);
-
- ioend->io_bio->bi_private = ioend;
- ioend->io_bio->bi_end_io = xfs_end_bio;
-
- /*
- * If we are failing the IO now, just mark the ioend with an
- * error and finish it. This will run IO completion immediately
- * as there is only one reference to the ioend at this point in
- * time.
- */
- if (status) {
- ioend->io_bio->bi_status = errno_to_blk_status(status);
- bio_endio(ioend->io_bio);
- return status;
- }
-
- submit_bio(ioend->io_bio);
- return 0;
-}
-
-static struct xfs_ioend *
-xfs_alloc_ioend(
- struct inode *inode,
- struct xfs_writepage_ctx *wpc,
- xfs_off_t offset,
- sector_t sector,
- struct writeback_control *wbc)
-{
- struct xfs_ioend *ioend;
- struct bio *bio;
-
- bio = bio_alloc_bioset(GFP_NOFS, BIO_MAX_PAGES, &xfs_ioend_bioset);
- bio_set_dev(bio, wpc->iomap.bdev);
- bio->bi_iter.bi_sector = sector;
- bio->bi_opf = REQ_OP_WRITE | wbc_to_write_flags(wbc);
- bio->bi_write_hint = inode->i_write_hint;
- wbc_init_bio(wbc, bio);
-
- ioend = container_of(bio, struct xfs_ioend, io_inline_bio);
- INIT_LIST_HEAD(&ioend->io_list);
- ioend->io_type = wpc->iomap.type;
- ioend->io_flags = wpc->iomap.flags;
- ioend->io_inode = inode;
- ioend->io_size = 0;
- ioend->io_offset = offset;
- ioend->io_append_trans = NULL;
- ioend->io_bio = bio;
- return ioend;
-}
-
-/*
- * Allocate a new bio, and chain the old bio to the new one.
- *
- * Note that we have to do perform the chaining in this unintuitive order
- * so that the bi_private linkage is set up in the right direction for the
- * traversal in xfs_destroy_ioend().
- */
-static struct bio *
-xfs_chain_bio(
- struct bio *prev)
-{
- struct bio *new;
-
- new = bio_alloc(GFP_NOFS, BIO_MAX_PAGES);
- bio_copy_dev(new, prev);/* also copies over blkcg information */
- new->bi_iter.bi_sector = bio_end_sector(prev);
- new->bi_opf = prev->bi_opf;
- new->bi_write_hint = prev->bi_write_hint;
-
- bio_chain(prev, new);
- bio_get(prev); /* for xfs_destroy_ioend */
- submit_bio(prev);
- return new;
-}
-
-/*
- * Test to see if we have an existing ioend structure that we could append to
- * first, otherwise finish off the current ioend and start another.
- */
-STATIC void
-xfs_add_to_ioend(
- struct inode *inode,
- xfs_off_t offset,
- struct page *page,
- struct iomap_page *iop,
- struct xfs_writepage_ctx *wpc,
- struct writeback_control *wbc,
- struct list_head *iolist)
-{
- sector_t sector = iomap_sector(&wpc->iomap, offset);
- unsigned len = i_blocksize(inode);
- unsigned poff = offset & (PAGE_SIZE - 1);
- bool merged, same_page = false;
-
- if (!wpc->ioend ||
- (wpc->iomap.flags & IOMAP_F_SHARED) !=
- (wpc->ioend->io_flags & IOMAP_F_SHARED) ||
- wpc->iomap.type != wpc->ioend->io_type ||
- sector != bio_end_sector(wpc->ioend->io_bio) ||
- offset != wpc->ioend->io_offset + wpc->ioend->io_size) {
- if (wpc->ioend)
- list_add(&wpc->ioend->io_list, iolist);
- wpc->ioend = xfs_alloc_ioend(inode, wpc, offset, sector, wbc);
- }
-
- merged = __bio_try_merge_page(wpc->ioend->io_bio, page, len, poff,
- &same_page);
-
- if (iop && !same_page)
- atomic_inc(&iop->write_count);
-
- if (!merged) {
- if (bio_full(wpc->ioend->io_bio, len))
- wpc->ioend->io_bio = xfs_chain_bio(wpc->ioend->io_bio);
- bio_add_page(wpc->ioend->io_bio, page, len, poff);
- }
-
- wpc->ioend->io_size += len;
- wbc_account_cgroup_owner(wbc, page, len);
-}
-
-STATIC void
-xfs_vm_invalidatepage(
- struct page *page,
- unsigned int offset,
- unsigned int length)
-{
- trace_xfs_invalidatepage(page->mapping->host, page, offset, length);
- iomap_invalidatepage(page, offset, length);
+ if ((ioend->io_flags & IOMAP_F_SHARED) ||
+ ioend->io_type == IOMAP_UNWRITTEN ||
+ ioend->io_private)
+ ioend->io_bio->bi_end_io = xfs_end_bio;
+ return status;
}

/*
@@ -816,8 +544,8 @@ xfs_vm_invalidatepage(
* transaction as there is no space left for block reservation (typically why we
* see a ENOSPC in writeback).
*/
-STATIC void
-xfs_aops_discard_page(
+static void
+xfs_discard_page(
struct page *page)
{
struct inode *inode = page->mapping->host;
@@ -839,246 +567,14 @@ xfs_aops_discard_page(
if (error && !XFS_FORCED_SHUTDOWN(mp))
xfs_alert(mp, "page discard unable to remove delalloc mapping.");
out_invalidate:
- xfs_vm_invalidatepage(page, 0, PAGE_SIZE);
-}
-
-/*
- * We implement an immediate ioend submission policy here to avoid needing to
- * chain multiple ioends and hence nest mempool allocations which can violate
- * forward progress guarantees we need to provide. The current ioend we are
- * adding blocks to is cached on the writepage context, and if the new block
- * does not append to the cached ioend it will create a new ioend and cache that
- * instead.
- *
- * If a new ioend is created and cached, the old ioend is returned and queued
- * locally for submission once the entire page is processed or an error has been
- * detected. While ioends are submitted immediately after they are completed,
- * batching optimisations are provided by higher level block plugging.
- *
- * At the end of a writeback pass, there will be a cached ioend remaining on the
- * writepage context that the caller will need to submit.
- */
-static int
-xfs_writepage_map(
- struct xfs_writepage_ctx *wpc,
- struct writeback_control *wbc,
- struct inode *inode,
- struct page *page,
- uint64_t end_offset)
-{
- LIST_HEAD(submit_list);
- struct iomap_page *iop = to_iomap_page(page);
- unsigned len = i_blocksize(inode);
- struct xfs_ioend *ioend, *next;
- uint64_t file_offset; /* file offset of page */
- int error = 0, count = 0, i;
-
- ASSERT(iop || i_blocksize(inode) == PAGE_SIZE);
- ASSERT(!iop || atomic_read(&iop->write_count) == 0);
-
- /*
- * Walk through the page to find areas to write back. If we run off the
- * end of the current map or find the current map invalid, grab a new
- * one.
- */
- for (i = 0, file_offset = page_offset(page);
- i < (PAGE_SIZE >> inode->i_blkbits) && file_offset < end_offset;
- i++, file_offset += len) {
- if (iop && !test_bit(i, iop->uptodate))
- continue;
-
- error = xfs_map_blocks(wpc, inode, file_offset);
- if (error)
- break;
- if (wpc->iomap.type == IOMAP_HOLE)
- continue;
- xfs_add_to_ioend(inode, file_offset, page, iop, wpc, wbc,
- &submit_list);
- count++;
- }
-
- ASSERT(wpc->ioend || list_empty(&submit_list));
- ASSERT(PageLocked(page));
- ASSERT(!PageWriteback(page));
-
- /*
- * On error, we have to fail the ioend here because we may have set
- * pages under writeback, we have to make sure we run IO completion to
- * mark the error state of the IO appropriately, so we can't cancel the
- * ioend directly here. That means we have to mark this page as under
- * writeback if we included any blocks from it in the ioend chain so
- * that completion treats it correctly.
- *
- * If we didn't include the page in the ioend, the on error we can
- * simply discard and unlock it as there are no other users of the page
- * now. The caller will still need to trigger submission of outstanding
- * ioends on the writepage context so they are treated correctly on
- * error.
- */
- if (unlikely(error)) {
- if (!count) {
- xfs_aops_discard_page(page);
- ClearPageUptodate(page);
- unlock_page(page);
- goto done;
- }
-
- /*
- * If the page was not fully cleaned, we need to ensure that the
- * higher layers come back to it correctly. That means we need
- * to keep the page dirty, and for WB_SYNC_ALL writeback we need
- * to ensure the PAGECACHE_TAG_TOWRITE index mark is not removed
- * so another attempt to write this page in this writeback sweep
- * will be made.
- */
- set_page_writeback_keepwrite(page);
- } else {
- clear_page_dirty_for_io(page);
- set_page_writeback(page);
- }
-
- unlock_page(page);
-
- /*
- * Preserve the original error if there was one, otherwise catch
- * submission errors here and propagate into subsequent ioend
- * submissions.
- */
- list_for_each_entry_safe(ioend, next, &submit_list, io_list) {
- int error2;
-
- list_del_init(&ioend->io_list);
- error2 = xfs_submit_ioend(wbc, ioend, error);
- if (error2 && !error)
- error = error2;
- }
-
- /*
- * We can end up here with no error and nothing to write only if we race
- * with a partial page truncate on a sub-page block sized filesystem.
- */
- if (!count)
- end_page_writeback(page);
-done:
- mapping_set_error(page->mapping, error);
- return error;
+ iomap_invalidatepage(page, 0, PAGE_SIZE);
}

-/*
- * Write out a dirty page.
- *
- * For delalloc space on the page we need to allocate space and flush it.
- * For unwritten space on the page we need to start the conversion to
- * regular allocated space.
- */
-STATIC int
-xfs_do_writepage(
- struct page *page,
- struct writeback_control *wbc,
- void *data)
-{
- struct xfs_writepage_ctx *wpc = data;
- struct inode *inode = page->mapping->host;
- loff_t offset;
- uint64_t end_offset;
- pgoff_t end_index;
-
- trace_xfs_writepage(inode, page, 0, 0);
-
- /*
- * Refuse to write the page out if we are called from reclaim context.
- *
- * This avoids stack overflows when called from deeply used stacks in
- * random callers for direct reclaim or memcg reclaim. We explicitly
- * allow reclaim from kswapd as the stack usage there is relatively low.
- *
- * This should never happen except in the case of a VM regression so
- * warn about it.
- */
- if (WARN_ON_ONCE((current->flags & (PF_MEMALLOC|PF_KSWAPD)) ==
- PF_MEMALLOC))
- goto redirty;
-
- /*
- * Given that we do not allow direct reclaim to call us, we should
- * never be called while in a filesystem transaction.
- */
- if (WARN_ON_ONCE(current->flags & PF_MEMALLOC_NOFS))
- goto redirty;
-
- /*
- * Is this page beyond the end of the file?
- *
- * The page index is less than the end_index, adjust the end_offset
- * to the highest offset that this page should represent.
- * -----------------------------------------------------
- * | file mapping | <EOF> |
- * -----------------------------------------------------
- * | Page ... | Page N-2 | Page N-1 | Page N | |
- * ^--------------------------------^----------|--------
- * | desired writeback range | see else |
- * ---------------------------------^------------------|
- */
- offset = i_size_read(inode);
- end_index = offset >> PAGE_SHIFT;
- if (page->index < end_index)
- end_offset = (xfs_off_t)(page->index + 1) << PAGE_SHIFT;
- else {
- /*
- * Check whether the page to write out is beyond or straddles
- * i_size or not.
- * -------------------------------------------------------
- * | file mapping | <EOF> |
- * -------------------------------------------------------
- * | Page ... | Page N-2 | Page N-1 | Page N | Beyond |
- * ^--------------------------------^-----------|---------
- * | | Straddles |
- * ---------------------------------^-----------|--------|
- */
- unsigned offset_into_page = offset & (PAGE_SIZE - 1);
-
- /*
- * Skip the page if it is fully outside i_size, e.g. due to a
- * truncate operation that is in progress. We must redirty the
- * page so that reclaim stops reclaiming it. Otherwise
- * xfs_vm_releasepage() is called on it and gets confused.
- *
- * Note that the end_index is unsigned long, it would overflow
- * if the given offset is greater than 16TB on 32-bit system
- * and if we do check the page is fully outside i_size or not
- * via "if (page->index >= end_index + 1)" as "end_index + 1"
- * will be evaluated to 0. Hence this page will be redirtied
- * and be written out repeatedly which would result in an
- * infinite loop, the user program that perform this operation
- * will hang. Instead, we can verify this situation by checking
- * if the page to write is totally beyond the i_size or if it's
- * offset is just equal to the EOF.
- */
- if (page->index > end_index ||
- (page->index == end_index && offset_into_page == 0))
- goto redirty;
-
- /*
- * The page straddles i_size. It must be zeroed out on each
- * and every writepage invocation because it may be mmapped.
- * "A file is mapped in multiples of the page size. For a file
- * that is not a multiple of the page size, the remaining
- * memory is zeroed when mapped, and writes to that region are
- * not written out to the file."
- */
- zero_user_segment(page, offset_into_page, PAGE_SIZE);
-
- /* Adjust the end_offset to the end of file */
- end_offset = offset;
- }
-
- return xfs_writepage_map(wpc, wbc, inode, page, end_offset);
-
-redirty:
- redirty_page_for_writepage(wbc, page);
- unlock_page(page);
- return 0;
-}
+static const struct iomap_writeback_ops xfs_writeback_ops = {
+ .map_blocks = xfs_map_blocks,
+ .submit_ioend = xfs_submit_ioend,
+ .discard_page = xfs_discard_page,
+};

STATIC int
xfs_vm_writepage(
@@ -1086,12 +582,8 @@ xfs_vm_writepage(
struct writeback_control *wbc)
{
struct xfs_writepage_ctx wpc = { };
- int ret;

- ret = xfs_do_writepage(page, wbc, &wpc);
- if (wpc.ioend)
- ret = xfs_submit_ioend(wbc, wpc.ioend, ret);
- return ret;
+ return iomap_writepage(page, wbc, &wpc.ctx, &xfs_writeback_ops);
}

STATIC int
@@ -1100,13 +592,9 @@ xfs_vm_writepages(
struct writeback_control *wbc)
{
struct xfs_writepage_ctx wpc = { };
- int ret;

xfs_iflags_clear(XFS_I(mapping->host), XFS_ITRUNCATED);
- ret = write_cache_pages(mapping, wbc, xfs_do_writepage, &wpc);
- if (wpc.ioend)
- ret = xfs_submit_ioend(wbc, wpc.ioend, ret);
- return ret;
+ return iomap_writepages(mapping, wbc, &wpc.ctx, &xfs_writeback_ops);
}

STATIC int
@@ -1119,15 +607,6 @@ xfs_dax_writepages(
xfs_find_bdev_for_inode(mapping->host), wbc);
}

-STATIC int
-xfs_vm_releasepage(
- struct page *page,
- gfp_t gfp_mask)
-{
- trace_xfs_releasepage(page->mapping->host, page, 0, 0);
- return iomap_releasepage(page, gfp_mask);
-}
-
STATIC sector_t
xfs_vm_bmap(
struct address_space *mapping,
@@ -1185,8 +664,8 @@ const struct address_space_operations xfs_address_space_operations = {
.writepage = xfs_vm_writepage,
.writepages = xfs_vm_writepages,
.set_page_dirty = iomap_set_page_dirty,
- .releasepage = xfs_vm_releasepage,
- .invalidatepage = xfs_vm_invalidatepage,
+ .releasepage = iomap_releasepage,
+ .invalidatepage = iomap_invalidatepage,
.bmap = xfs_vm_bmap,
.direct_IO = noop_direct_IO,
.migratepage = iomap_migrate_page,
diff --git a/fs/xfs/xfs_aops.h b/fs/xfs/xfs_aops.h
index c2756ed50b0d..687b11f34fa2 100644
--- a/fs/xfs/xfs_aops.h
+++ b/fs/xfs/xfs_aops.h
@@ -6,23 +6,6 @@
#ifndef __XFS_AOPS_H__
#define __XFS_AOPS_H__

-extern struct bio_set xfs_ioend_bioset;
-
-/*
- * Structure for buffered I/O completions.
- */
-struct xfs_ioend {
- struct list_head io_list; /* next ioend in chain */
- u16 io_type;
- u16 io_flags; /* IOMAP_F_* */
- struct inode *io_inode; /* file being written to */
- size_t io_size; /* size of the extent */
- xfs_off_t io_offset; /* offset in the file */
- struct xfs_trans *io_append_trans;/* xact. for size update */
- struct bio *io_bio; /* bio being built */
- struct bio io_inline_bio; /* MUST BE LAST! */
-};
-
extern const struct address_space_operations xfs_address_space_operations;
extern const struct address_space_operations xfs_dax_aops;

diff --git a/fs/xfs/xfs_super.c b/fs/xfs/xfs_super.c
index 8d1df9f8be07..0a8cf6b87a21 100644
--- a/fs/xfs/xfs_super.c
+++ b/fs/xfs/xfs_super.c
@@ -40,7 +40,6 @@
#include <linux/parser.h>

static const struct super_operations xfs_super_operations;
-struct bio_set xfs_ioend_bioset;

static struct kset *xfs_kset; /* top-level xfs sysfs dir */
#ifdef DEBUG
@@ -1853,15 +1852,10 @@ MODULE_ALIAS_FS("xfs");
STATIC int __init
xfs_init_zones(void)
{
- if (bioset_init(&xfs_ioend_bioset, 4 * (PAGE_SIZE / SECTOR_SIZE),
- offsetof(struct xfs_ioend, io_inline_bio),
- BIOSET_NEED_BVECS))
- goto out;
-
xfs_log_ticket_zone = kmem_zone_init(sizeof(xlog_ticket_t),
"xfs_log_ticket");
if (!xfs_log_ticket_zone)
- goto out_free_ioend_bioset;
+ goto out;

xfs_bmap_free_item_zone = kmem_zone_init(
sizeof(struct xfs_extent_free_item),
@@ -1996,8 +1990,6 @@ xfs_init_zones(void)
kmem_zone_destroy(xfs_bmap_free_item_zone);
out_destroy_log_ticket_zone:
kmem_zone_destroy(xfs_log_ticket_zone);
- out_free_ioend_bioset:
- bioset_exit(&xfs_ioend_bioset);
out:
return -ENOMEM;
}
@@ -2028,7 +2020,6 @@ xfs_destroy_zones(void)
kmem_zone_destroy(xfs_btree_cur_zone);
kmem_zone_destroy(xfs_bmap_free_item_zone);
kmem_zone_destroy(xfs_log_ticket_zone);
- bioset_exit(&xfs_ioend_bioset);
}

STATIC int __init
diff --git a/fs/xfs/xfs_trace.h b/fs/xfs/xfs_trace.h
index eae4b29c174e..cbb23d7a3554 100644
--- a/fs/xfs/xfs_trace.h
+++ b/fs/xfs/xfs_trace.h
@@ -1158,45 +1158,6 @@ DEFINE_RW_EVENT(xfs_file_buffered_write);
DEFINE_RW_EVENT(xfs_file_direct_write);
DEFINE_RW_EVENT(xfs_file_dax_write);

-DECLARE_EVENT_CLASS(xfs_page_class,
- TP_PROTO(struct inode *inode, struct page *page, unsigned long off,
- unsigned int len),
- TP_ARGS(inode, page, off, len),
- TP_STRUCT__entry(
- __field(dev_t, dev)
- __field(xfs_ino_t, ino)
- __field(pgoff_t, pgoff)
- __field(loff_t, size)
- __field(unsigned long, offset)
- __field(unsigned int, length)
- ),
- TP_fast_assign(
- __entry->dev = inode->i_sb->s_dev;
- __entry->ino = XFS_I(inode)->i_ino;
- __entry->pgoff = page_offset(page);
- __entry->size = i_size_read(inode);
- __entry->offset = off;
- __entry->length = len;
- ),
- TP_printk("dev %d:%d ino 0x%llx pgoff 0x%lx size 0x%llx offset %lx "
- "length %x",
- MAJOR(__entry->dev), MINOR(__entry->dev),
- __entry->ino,
- __entry->pgoff,
- __entry->size,
- __entry->offset,
- __entry->length)
-)
-
-#define DEFINE_PAGE_EVENT(name) \
-DEFINE_EVENT(xfs_page_class, name, \
- TP_PROTO(struct inode *inode, struct page *page, unsigned long off, \
- unsigned int len), \
- TP_ARGS(inode, page, off, len))
-DEFINE_PAGE_EVENT(xfs_writepage);
-DEFINE_PAGE_EVENT(xfs_releasepage);
-DEFINE_PAGE_EVENT(xfs_invalidatepage);
-
DECLARE_EVENT_CLASS(xfs_imap_class,
TP_PROTO(struct xfs_inode *ip, xfs_off_t offset, ssize_t count,
int whichfork, struct xfs_bmbt_irec *irec),
--
2.20.1