[PATCH 04/14] xfs: use a struct iomap in xfs_writepage_ctx

Christoph Hellwig
2019-10-17T17:57:39Z

In preparation for moving the XFS writeback code to fs/iomap.c, switch
it to use struct iomap instead of the XFS-specific struct xfs_bmbt_irec.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Carlos Maiolino <cmaiolino@redhat.com>
Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com>
---
fs/xfs/libxfs/xfs_bmap.c | 14 +++++--
fs/xfs/libxfs/xfs_bmap.h | 3 +-
fs/xfs/xfs_aops.c | 82 +++++++++++++++++++---------------------
fs/xfs/xfs_aops.h | 2 +-
4 files changed, 50 insertions(+), 51 deletions(-)

diff --git a/fs/xfs/libxfs/xfs_bmap.c b/fs/xfs/libxfs/xfs_bmap.c
index 02469d59c787..ef75e223cb70 100644
--- a/fs/xfs/libxfs/xfs_bmap.c
+++ b/fs/xfs/libxfs/xfs_bmap.c
@@ -34,6 +34,7 @@
#include "xfs_ag_resv.h"
#include "xfs_refcount.h"
#include "xfs_icache.h"
+#include "xfs_iomap.h"

kmem_zone_t *xfs_bmap_free_item_zone;
@@ -4456,16 +4457,21 @@ int
xfs_bmapi_convert_delalloc(
struct xfs_inode *ip,
int whichfork,
- xfs_fileoff_t offset_fsb,
- struct xfs_bmbt_irec *imap,
+ xfs_off_t offset,
+ struct iomap *iomap,
unsigned int *seq)
{
struct xfs_ifork *ifp = XFS_IFORK_PTR(ip, whichfork);
struct xfs_mount *mp = ip->i_mount;
+ xfs_fileoff_t offset_fsb = XFS_B_TO_FSBT(mp, offset);
struct xfs_bmalloca bma = { NULL };
+ u16 flags = 0;
struct xfs_trans *tp;
int error;

+ if (whichfork == XFS_COW_FORK)
+ flags |= IOMAP_F_SHARED;
+
/*
* Space for the extent and indirect blocks was reserved when the
* delalloc extent was created so there's no need to do so here.
@@ -4495,7 +4501,7 @@ xfs_bmapi_convert_delalloc(
* the extent. Just return the real extent at this offset.
*/
if (!isnullstartblock(bma.got.br_startblock)) {
- *imap = bma.got;
+ xfs_bmbt_to_iomap(ip, iomap, &bma.got, flags);
*seq = READ_ONCE(ifp->if_seq);
goto out_trans_cancel;
}
@@ -4528,7 +4534,7 @@ xfs_bmapi_convert_delalloc(
XFS_STATS_INC(mp, xs_xstrat_quick);

ASSERT(!isnullstartblock(bma.got.br_startblock));
- *imap = bma.got;
+ xfs_bmbt_to_iomap(ip, iomap, &bma.got, flags);
*seq = READ_ONCE(ifp->if_seq);

if (whichfork == XFS_COW_FORK)
diff --git a/fs/xfs/libxfs/xfs_bmap.h b/fs/xfs/libxfs/xfs_bmap.h
index e2798c6f3a5f..14d25e0b7d9c 100644
--- a/fs/xfs/libxfs/xfs_bmap.h
+++ b/fs/xfs/libxfs/xfs_bmap.h
@@ -228,8 +228,7 @@ int xfs_bmapi_reserve_delalloc(struct xfs_inode *ip, int whichfork,
struct xfs_bmbt_irec *got, struct xfs_iext_cursor *cur,
int eof);
int xfs_bmapi_convert_delalloc(struct xfs_inode *ip, int whichfork,
- xfs_fileoff_t offset_fsb, struct xfs_bmbt_irec *imap,
- unsigned int *seq);
+ xfs_off_t offset, struct iomap *iomap, unsigned int *seq);
int xfs_bmap_add_extent_unwritten_real(struct xfs_trans *tp,
struct xfs_inode *ip, int whichfork,
struct xfs_iext_cursor *icur, struct xfs_btree_cur **curp,
diff --git a/fs/xfs/xfs_aops.c b/fs/xfs/xfs_aops.c
index f16d5f196c6b..91899de2be09 100644
--- a/fs/xfs/xfs_aops.c
+++ b/fs/xfs/xfs_aops.c
@@ -22,7 +22,7 @@
* structure owned by writepages passed to individual writepage calls
*/
struct xfs_writepage_ctx {
- struct xfs_bmbt_irec imap;
+ struct iomap iomap;
int fork;
unsigned int data_seq;
unsigned int cow_seq;
@@ -267,7 +267,7 @@ xfs_end_ioend(
*/
if (ioend->io_fork == XFS_COW_FORK)
error = xfs_reflink_end_cow(ip, offset, size);
- else if (ioend->io_state == XFS_EXT_UNWRITTEN)
+ 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);
@@ -300,8 +300,8 @@ xfs_ioend_can_merge(
return false;
if ((ioend->io_fork == XFS_COW_FORK) ^ (next->io_fork == XFS_COW_FORK))
return false;
- if ((ioend->io_state == XFS_EXT_UNWRITTEN) ^
- (next->io_state == XFS_EXT_UNWRITTEN))
+ 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;
@@ -403,7 +403,7 @@ xfs_end_bio(
unsigned long flags;

if (ioend->io_fork == XFS_COW_FORK ||
- ioend->io_state == XFS_EXT_UNWRITTEN ||
+ 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))
@@ -423,10 +423,10 @@ static bool
xfs_imap_valid(
struct xfs_writepage_ctx *wpc,
struct xfs_inode *ip,
- xfs_fileoff_t offset_fsb)
+ loff_t offset)
{
- if (offset_fsb < wpc->imap.br_startoff ||
- offset_fsb >= wpc->imap.br_startoff + wpc->imap.br_blockcount)
+ if (offset < wpc->iomap.offset ||
+ offset >= wpc->iomap.offset + wpc->iomap.length)
return false;
/*
* If this is a COW mapping, it is sufficient to check that the mapping
@@ -453,7 +453,7 @@ xfs_imap_valid(

/*
* Pass in a dellalloc extent and convert it to real extents, return the real
- * extent that maps offset_fsb in wpc->imap.
+ * extent that maps offset_fsb in wpc->iomap.
*
* The current page is held locked so nothing could have removed the block
* backing offset_fsb, although it could have moved from the COW to the data
@@ -463,23 +463,23 @@ static int
xfs_convert_blocks(
struct xfs_writepage_ctx *wpc,
struct xfs_inode *ip,
- xfs_fileoff_t offset_fsb)
+ loff_t offset)
{
int error;

/*
- * Attempt to allocate whatever delalloc extent currently backs
- * offset_fsb and put the result into wpc->imap. Allocate in a loop
- * because it may take several attempts to allocate real blocks for a
- * contiguous delalloc extent if free space is sufficiently fragmented.
+ * Attempt to allocate whatever delalloc extent currently backs offset
+ * and put the result into wpc->iomap. Allocate in a loop because it
+ * may take several attempts to allocate real blocks for a contiguous
+ * delalloc extent if free space is sufficiently fragmented.
*/
do {
- error = xfs_bmapi_convert_delalloc(ip, wpc->fork, offset_fsb,
- &wpc->imap, wpc->fork == XFS_COW_FORK ?
+ error = xfs_bmapi_convert_delalloc(ip, wpc->fork, offset,
+ &wpc->iomap, wpc->fork == XFS_COW_FORK ?
&wpc->cow_seq : &wpc->data_seq);
if (error)
return error;
- } while (wpc->imap.br_startoff + wpc->imap.br_blockcount <= offset_fsb);
+ } while (wpc->iomap.offset + wpc->iomap.length <= offset);

return 0;
}
@@ -519,7 +519,7 @@ xfs_map_blocks(
* against concurrent updates and provides a memory barrier on the way
* out that ensures that we always see the current value.
*/
- if (xfs_imap_valid(wpc, ip, offset_fsb))
+ if (xfs_imap_valid(wpc, ip, offset))
return 0;

/*
@@ -552,7 +552,7 @@ xfs_map_blocks(
* No COW extent overlap. Revalidate now that we may have updated
* ->cow_seq. If the data mapping is still valid, we're done.
*/
- if (xfs_imap_valid(wpc, ip, offset_fsb)) {
+ if (xfs_imap_valid(wpc, ip, offset)) {
xfs_iunlock(ip, XFS_ILOCK_SHARED);
return 0;
}
@@ -592,11 +592,11 @@ xfs_map_blocks(
isnullstartblock(imap.br_startblock))
goto allocate_blocks;

- wpc->imap = imap;
+ xfs_bmbt_to_iomap(ip, &wpc->iomap, &imap, 0);
trace_xfs_map_blocks_found(ip, offset, count, wpc->fork, &imap);
return 0;
allocate_blocks:
- error = xfs_convert_blocks(wpc, ip, offset_fsb);
+ error = xfs_convert_blocks(wpc, ip, offset);
if (error) {
/*
* If we failed to find the extent in the COW fork we might have
@@ -616,12 +616,15 @@ xfs_map_blocks(
* original delalloc one. Trim the return extent to the next COW
* boundary again to force a re-lookup.
*/
- if (wpc->fork != XFS_COW_FORK && cow_fsb != NULLFILEOFF &&
- cow_fsb < wpc->imap.br_startoff + wpc->imap.br_blockcount)
- wpc->imap.br_blockcount = cow_fsb - wpc->imap.br_startoff;
+ if (wpc->fork != XFS_COW_FORK && cow_fsb != NULLFILEOFF) {
+ loff_t cow_offset = XFS_FSB_TO_B(mp, cow_fsb);
+
+ if (cow_offset < wpc->iomap.offset + wpc->iomap.length)
+ wpc->iomap.length = cow_offset - wpc->iomap.offset;
+ }

- ASSERT(wpc->imap.br_startoff <= offset_fsb);
- ASSERT(wpc->imap.br_startoff + wpc->imap.br_blockcount > offset_fsb);
+ ASSERT(wpc->iomap.offset <= offset);
+ ASSERT(wpc->iomap.offset + wpc->iomap.length > offset);
trace_xfs_map_blocks_alloc(ip, offset, count, wpc->fork, &imap);
return 0;
}
@@ -664,7 +667,7 @@ xfs_submit_ioend(
/* Reserve log space if we might write beyond the on-disk inode size. */
if (!status &&
(ioend->io_fork == XFS_COW_FORK ||
- ioend->io_state != XFS_EXT_UNWRITTEN) &&
+ ioend->io_type != IOMAP_UNWRITTEN) &&
xfs_ioend_is_append(ioend) &&
!ioend->io_append_trans)
status = xfs_setfilesize_trans_alloc(ioend);
@@ -693,10 +696,8 @@ xfs_submit_ioend(
static struct xfs_ioend *
xfs_alloc_ioend(
struct inode *inode,
- int fork,
- xfs_exntst_t state,
+ struct xfs_writepage_ctx *wpc,
xfs_off_t offset,
- struct block_device *bdev,
sector_t sector,
struct writeback_control *wbc)
{
@@ -704,7 +705,7 @@ xfs_alloc_ioend(
struct bio *bio;

bio = bio_alloc_bioset(GFP_NOFS, BIO_MAX_PAGES, &xfs_ioend_bioset);
- bio_set_dev(bio, bdev);
+ 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;
@@ -712,8 +713,8 @@ xfs_alloc_ioend(

ioend = container_of(bio, struct xfs_ioend, io_inline_bio);
INIT_LIST_HEAD(&ioend->io_list);
- ioend->io_fork = fork;
- ioend->io_state = state;
+ ioend->io_fork = wpc->fork;
+ ioend->io_type = wpc->iomap.type;
ioend->io_inode = inode;
ioend->io_size = 0;
ioend->io_offset = offset;
@@ -761,26 +762,19 @@ xfs_add_to_ioend(
struct writeback_control *wbc,
struct list_head *iolist)
{
- struct xfs_inode *ip = XFS_I(inode);
- struct xfs_mount *mp = ip->i_mount;
- struct block_device *bdev = xfs_find_bdev_for_inode(inode);
+ sector_t sector = iomap_sector(&wpc->iomap, offset);
unsigned len = i_blocksize(inode);
unsigned poff = offset & (PAGE_SIZE - 1);
bool merged, same_page = false;
- sector_t sector;
-
- sector = xfs_fsb_to_db(ip, wpc->imap.br_startblock) +
- ((offset - XFS_FSB_TO_B(mp, wpc->imap.br_startoff)) >> 9);

if (!wpc->ioend ||
wpc->fork != wpc->ioend->io_fork ||
- wpc->imap.br_state != wpc->ioend->io_state ||
+ 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->fork,
- wpc->imap.br_state, offset, bdev, sector, wbc);
+ wpc->ioend = xfs_alloc_ioend(inode, wpc, offset, sector, wbc);
}

merged = __bio_try_merge_page(wpc->ioend->io_bio, page, len, poff,
@@ -894,7 +888,7 @@ xfs_writepage_map(
error = xfs_map_blocks(wpc, inode, file_offset);
if (error)
break;
- if (wpc->imap.br_startblock == HOLESTARTBLOCK)
+ if (wpc->iomap.type == IOMAP_HOLE)
continue;
xfs_add_to_ioend(inode, file_offset, page, iop, wpc, wbc,
&submit_list);
diff --git a/fs/xfs/xfs_aops.h b/fs/xfs/xfs_aops.h
index 45a1ea240cbb..4af8ec0115cd 100644
--- a/fs/xfs/xfs_aops.h
+++ b/fs/xfs/xfs_aops.h
@@ -14,7 +14,7 @@ extern struct bio_set xfs_ioend_bioset;
struct xfs_ioend {
struct list_head io_list; /* next ioend in chain */
int io_fork; /* inode fork written back */
- xfs_exntst_t io_state; /* extent state */
+ u16 io_type;
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 */
--
2.20.1