[XFS] Initial pass at going directly-to-bio on the buffered IO path. This
allows us to submit much larger I/Os instead of sending down lots of small
buffer_heads. To do this we need to have a rather complicated I/O
submission and completion tracking infrastructure. Part of the latter has
been merged already a long time ago for direct I/O support. Part of the
problem is that we need to track sub-pagesize regions and for that we
still need buffer_heads for the time beeing. Long-term I hope we can move
to better data strucutures and/or maybe move this to fs/mpage.c instead of
having it in XFS. Original patch from Nathan Scott with various updates
from David Chinner and Christoph Hellwig.
SGI-PV: 947118
SGI-Modid: xfs-linux-melb:xfs-kern:203822a
Signed-off-by: Christoph Hellwig <hch@sgi.com>
Signed-off-by: Nathan Scott <nathans@sgi.com>
diff --git a/fs/xfs/linux-2.6/xfs_aops.c b/fs/xfs/linux-2.6/xfs_aops.c
index 3f6b9e2..e99d04d 100644
--- a/fs/xfs/linux-2.6/xfs_aops.c
+++ b/fs/xfs/linux-2.6/xfs_aops.c
@@ -43,8 +43,6 @@
#include <linux/writeback.h>
STATIC void xfs_count_page_state(struct page *, int *, int *, int *);
-STATIC void xfs_convert_page(struct inode *, struct page *, xfs_iomap_t *,
- struct writeback_control *wbc, void *, int, int);
#if defined(XFS_RW_TRACE)
void
@@ -58,7 +56,7 @@
bhv_desc_t *bdp;
vnode_t *vp = LINVFS_GET_VP(inode);
loff_t isize = i_size_read(inode);
- loff_t offset = (loff_t)page->index << PAGE_CACHE_SHIFT;
+ loff_t offset = page_offset(page);
int delalloc = -1, unmapped = -1, unwritten = -1;
if (page_has_buffers(page))
@@ -103,15 +101,56 @@
queue_work(xfsdatad_workqueue, &ioend->io_work);
}
+/*
+ * We're now finished for good with this ioend structure.
+ * Update the page state via the associated buffer_heads,
+ * release holds on the inode and bio, and finally free
+ * up memory. Do not use the ioend after this.
+ */
STATIC void
xfs_destroy_ioend(
xfs_ioend_t *ioend)
{
+ struct buffer_head *bh, *next;
+
+ for (bh = ioend->io_buffer_head; bh; bh = next) {
+ next = bh->b_private;
+ bh->b_end_io(bh, ioend->io_uptodate);
+ }
+
vn_iowake(ioend->io_vnode);
mempool_free(ioend, xfs_ioend_pool);
}
/*
+ * Buffered IO write completion for delayed allocate extents.
+ * TODO: Update ondisk isize now that we know the file data
+ * has been flushed (i.e. the notorious "NULL file" problem).
+ */
+STATIC void
+xfs_end_bio_delalloc(
+ void *data)
+{
+ xfs_ioend_t *ioend = data;
+
+ xfs_destroy_ioend(ioend);
+}
+
+/*
+ * Buffered IO write completion for regular, written extents.
+ */
+STATIC void
+xfs_end_bio_written(
+ void *data)
+{
+ xfs_ioend_t *ioend = data;
+
+ xfs_destroy_ioend(ioend);
+}
+
+/*
+ * IO write completion for unwritten extents.
+ *
* Issue transactions to convert a buffer range from unwritten
* to written extents.
*/
@@ -123,21 +162,10 @@
vnode_t *vp = ioend->io_vnode;
xfs_off_t offset = ioend->io_offset;
size_t size = ioend->io_size;
- struct buffer_head *bh, *next;
int error;
if (ioend->io_uptodate)
VOP_BMAP(vp, offset, size, BMAPI_UNWRITTEN, NULL, NULL, error);
-
- /* ioend->io_buffer_head is only non-NULL for buffered I/O */
- for (bh = ioend->io_buffer_head; bh; bh = next) {
- next = bh->b_private;
-
- bh->b_end_io = NULL;
- clear_buffer_unwritten(bh);
- end_buffer_async_write(bh, ioend->io_uptodate);
- }
-
xfs_destroy_ioend(ioend);
}
@@ -149,7 +177,8 @@
*/
STATIC xfs_ioend_t *
xfs_alloc_ioend(
- struct inode *inode)
+ struct inode *inode,
+ unsigned int type)
{
xfs_ioend_t *ioend;
@@ -162,45 +191,25 @@
*/
atomic_set(&ioend->io_remaining, 1);
ioend->io_uptodate = 1; /* cleared if any I/O fails */
+ ioend->io_list = NULL;
+ ioend->io_type = type;
ioend->io_vnode = LINVFS_GET_VP(inode);
ioend->io_buffer_head = NULL;
+ ioend->io_buffer_tail = NULL;
atomic_inc(&ioend->io_vnode->v_iocount);
ioend->io_offset = 0;
ioend->io_size = 0;
- INIT_WORK(&ioend->io_work, xfs_end_bio_unwritten, ioend);
+ if (type == IOMAP_UNWRITTEN)
+ INIT_WORK(&ioend->io_work, xfs_end_bio_unwritten, ioend);
+ else if (type == IOMAP_DELAY)
+ INIT_WORK(&ioend->io_work, xfs_end_bio_delalloc, ioend);
+ else
+ INIT_WORK(&ioend->io_work, xfs_end_bio_written, ioend);
return ioend;
}
-void
-linvfs_unwritten_done(
- struct buffer_head *bh,
- int uptodate)
-{
- xfs_ioend_t *ioend = bh->b_private;
- static spinlock_t unwritten_done_lock = SPIN_LOCK_UNLOCKED;
- unsigned long flags;
-
- ASSERT(buffer_unwritten(bh));
- bh->b_end_io = NULL;
-
- if (!uptodate)
- ioend->io_uptodate = 0;
-
- /*
- * Deep magic here. We reuse b_private in the buffer_heads to build
- * a chain for completing the I/O from user context after we've issued
- * a transaction to convert the unwritten extent.
- */
- spin_lock_irqsave(&unwritten_done_lock, flags);
- bh->b_private = ioend->io_buffer_head;
- ioend->io_buffer_head = bh;
- spin_unlock_irqrestore(&unwritten_done_lock, flags);
-
- xfs_finish_ioend(ioend);
-}
-
STATIC int
xfs_map_blocks(
struct inode *inode,
@@ -228,7 +237,7 @@
xfs_iomap_t *iomapp,
unsigned long offset)
{
- loff_t full_offset; /* offset from start of file */
+ xfs_off_t full_offset; /* offset from start of file */
ASSERT(offset < PAGE_CACHE_SIZE);
@@ -243,16 +252,223 @@
return NULL;
}
+/*
+ * BIO completion handler for buffered IO.
+ */
+STATIC int
+xfs_end_bio(
+ struct bio *bio,
+ unsigned int bytes_done,
+ int error)
+{
+ xfs_ioend_t *ioend = bio->bi_private;
+
+ if (bio->bi_size)
+ return 1;
+
+ ASSERT(ioend);
+ ASSERT(atomic_read(&bio->bi_cnt) >= 1);
+
+ /* Toss bio and pass work off to an xfsdatad thread */
+ if (!test_bit(BIO_UPTODATE, &bio->bi_flags))
+ ioend->io_uptodate = 0;
+ bio->bi_private = NULL;
+ bio->bi_end_io = NULL;
+
+ bio_put(bio);
+ xfs_finish_ioend(ioend);
+ return 0;
+}
+
+STATIC void
+xfs_submit_ioend_bio(
+ xfs_ioend_t *ioend,
+ struct bio *bio)
+{
+ atomic_inc(&ioend->io_remaining);
+
+ bio->bi_private = ioend;
+ bio->bi_end_io = xfs_end_bio;
+
+ submit_bio(WRITE, bio);
+ ASSERT(!bio_flagged(bio, BIO_EOPNOTSUPP));
+ bio_put(bio);
+}
+
+STATIC struct bio *
+xfs_alloc_ioend_bio(
+ struct buffer_head *bh)
+{
+ struct bio *bio;
+ int nvecs = bio_get_nr_vecs(bh->b_bdev);
+
+ do {
+ bio = bio_alloc(GFP_NOIO, nvecs);
+ nvecs >>= 1;
+ } while (!bio);
+
+ ASSERT(bio->bi_private == NULL);
+ bio->bi_sector = bh->b_blocknr * (bh->b_size >> 9);
+ bio->bi_bdev = bh->b_bdev;
+ bio_get(bio);
+ return bio;
+}
+
+STATIC void
+xfs_start_buffer_writeback(
+ struct buffer_head *bh)
+{
+ ASSERT(buffer_mapped(bh));
+ ASSERT(buffer_locked(bh));
+ ASSERT(!buffer_delay(bh));
+ ASSERT(!buffer_unwritten(bh));
+
+ mark_buffer_async_write(bh);
+ set_buffer_uptodate(bh);
+ clear_buffer_dirty(bh);
+}
+
+STATIC void
+xfs_start_page_writeback(
+ struct page *page,
+ struct writeback_control *wbc,
+ int clear_dirty,
+ int buffers)
+{
+ ASSERT(PageLocked(page));
+ ASSERT(!PageWriteback(page));
+ set_page_writeback(page);
+ if (clear_dirty)
+ clear_page_dirty(page);
+ unlock_page(page);
+ if (!buffers) {
+ end_page_writeback(page);
+ wbc->pages_skipped++; /* We didn't write this page */
+ }
+}
+
+static inline int bio_add_buffer(struct bio *bio, struct buffer_head *bh)
+{
+ return bio_add_page(bio, bh->b_page, bh->b_size, bh_offset(bh));
+}
+
+/*
+ * Submit all of the bios for all of the ioends we have saved up,
+ * covering the initial writepage page and also any probed pages.
+ */
+STATIC void
+xfs_submit_ioend(
+ xfs_ioend_t *ioend)
+{
+ xfs_ioend_t *next;
+ struct buffer_head *bh;
+ struct bio *bio;
+ sector_t lastblock = 0;
+
+ do {
+ next = ioend->io_list;
+ bio = NULL;
+
+ for (bh = ioend->io_buffer_head; bh; bh = bh->b_private) {
+ xfs_start_buffer_writeback(bh);
+
+ if (!bio) {
+ retry:
+ bio = xfs_alloc_ioend_bio(bh);
+ } else if (bh->b_blocknr != lastblock + 1) {
+ xfs_submit_ioend_bio(ioend, bio);
+ goto retry;
+ }
+
+ if (bio_add_buffer(bio, bh) != bh->b_size) {
+ xfs_submit_ioend_bio(ioend, bio);
+ goto retry;
+ }
+
+ lastblock = bh->b_blocknr;
+ }
+ if (bio)
+ xfs_submit_ioend_bio(ioend, bio);
+ xfs_finish_ioend(ioend);
+ } while ((ioend = next) != NULL);
+}
+
+/*
+ * Cancel submission of all buffer_heads so far in this endio.
+ * Toss the endio too. Only ever called for the initial page
+ * in a writepage request, so only ever one page.
+ */
+STATIC void
+xfs_cancel_ioend(
+ xfs_ioend_t *ioend)
+{
+ xfs_ioend_t *next;
+ struct buffer_head *bh, *next_bh;
+
+ do {
+ next = ioend->io_list;
+ bh = ioend->io_buffer_head;
+ do {
+ next_bh = bh->b_private;
+ clear_buffer_async_write(bh);
+ unlock_buffer(bh);
+ } while ((bh = next_bh) != NULL);
+
+ vn_iowake(ioend->io_vnode);
+ mempool_free(ioend, xfs_ioend_pool);
+ } while ((ioend = next) != NULL);
+}
+
+/*
+ * Test to see if we've been building up a completion structure for
+ * earlier buffers -- if so, we try to append to this ioend if we
+ * can, otherwise we finish off any current ioend and start another.
+ * Return true if we've finished the given ioend.
+ */
+STATIC void
+xfs_add_to_ioend(
+ struct inode *inode,
+ struct buffer_head *bh,
+ unsigned int p_offset,
+ unsigned int type,
+ xfs_ioend_t **result,
+ int need_ioend)
+{
+ xfs_ioend_t *ioend = *result;
+
+ if (!ioend || need_ioend || type != ioend->io_type) {
+ xfs_ioend_t *previous = *result;
+ xfs_off_t offset;
+
+ offset = (xfs_off_t)bh->b_page->index << PAGE_CACHE_SHIFT;
+ offset += p_offset;
+ ioend = xfs_alloc_ioend(inode, type);
+ ioend->io_offset = offset;
+ ioend->io_buffer_head = bh;
+ ioend->io_buffer_tail = bh;
+ if (previous)
+ previous->io_list = ioend;
+ *result = ioend;
+ } else {
+ ioend->io_buffer_tail->b_private = bh;
+ ioend->io_buffer_tail = bh;
+ }
+
+ bh->b_private = NULL;
+ ioend->io_size += bh->b_size;
+}
+
STATIC void
xfs_map_at_offset(
struct page *page,
struct buffer_head *bh,
unsigned long offset,
int block_bits,
- xfs_iomap_t *iomapp)
+ xfs_iomap_t *iomapp,
+ xfs_ioend_t *ioend)
{
xfs_daddr_t bn;
- loff_t delta;
+ xfs_off_t delta;
int sector_shift;
ASSERT(!(iomapp->iomap_flags & IOMAP_HOLE));
@@ -276,60 +492,7 @@
bh->b_bdev = iomapp->iomap_target->bt_bdev;
set_buffer_mapped(bh);
clear_buffer_delay(bh);
-}
-
-/*
- * Look for a page at index which is unlocked and contains our
- * unwritten extent flagged buffers at its head. Returns page
- * locked and with an extra reference count, and length of the
- * unwritten extent component on this page that we can write,
- * in units of filesystem blocks.
- */
-STATIC struct page *
-xfs_probe_unwritten_page(
- struct address_space *mapping,
- pgoff_t index,
- xfs_iomap_t *iomapp,
- xfs_ioend_t *ioend,
- unsigned long max_offset,
- unsigned long *fsbs,
- unsigned int bbits)
-{
- struct page *page;
-
- page = find_trylock_page(mapping, index);
- if (!page)
- return NULL;
- if (PageWriteback(page))
- goto out;
-
- if (page->mapping && page_has_buffers(page)) {
- struct buffer_head *bh, *head;
- unsigned long p_offset = 0;
-
- *fsbs = 0;
- bh = head = page_buffers(page);
- do {
- if (!buffer_unwritten(bh) || !buffer_uptodate(bh))
- break;
- if (!xfs_offset_to_map(page, iomapp, p_offset))
- break;
- if (p_offset >= max_offset)
- break;
- xfs_map_at_offset(page, bh, p_offset, bbits, iomapp);
- set_buffer_unwritten_io(bh);
- bh->b_private = ioend;
- p_offset += bh->b_size;
- (*fsbs)++;
- } while ((bh = bh->b_this_page) != head);
-
- if (p_offset)
- return page;
- }
-
-out:
- unlock_page(page);
- return NULL;
+ clear_buffer_unwritten(bh);
}
/*
@@ -372,15 +535,16 @@
return ret;
}
-STATIC unsigned int
+STATIC size_t
xfs_probe_unmapped_cluster(
struct inode *inode,
struct page *startpage,
struct buffer_head *bh,
struct buffer_head *head)
{
+ size_t len, total = 0;
pgoff_t tindex, tlast, tloff;
- unsigned int pg_offset, len, total = 0;
+ unsigned int pg_offset;
struct address_space *mapping = inode->i_mapping;
/* First sum forwards in this page */
@@ -414,14 +578,15 @@
}
/*
- * Probe for a given page (index) in the inode and test if it is delayed
- * and without unwritten buffers. Returns page locked and with an extra
- * reference count.
+ * Probe for a given page (index) in the inode and test if it is suitable
+ * for writing as part of an unwritten or delayed allocate extent.
+ * Returns page locked and with an extra reference count if so, else NULL.
*/
STATIC struct page *
-xfs_probe_delalloc_page(
+xfs_probe_delayed_page(
struct inode *inode,
- pgoff_t index)
+ pgoff_t index,
+ unsigned int type)
{
struct page *page;
@@ -437,12 +602,12 @@
bh = head = page_buffers(page);
do {
- if (buffer_unwritten(bh)) {
- acceptable = 0;
+ if (buffer_unwritten(bh))
+ acceptable = (type == IOMAP_UNWRITTEN);
+ else if (buffer_delay(bh))
+ acceptable = (type == IOMAP_DELAY);
+ else
break;
- } else if (buffer_delay(bh)) {
- acceptable = 1;
- }
} while ((bh = bh->b_this_page) != head);
if (acceptable)
@@ -454,161 +619,30 @@
return NULL;
}
-STATIC int
-xfs_map_unwritten(
- struct inode *inode,
- struct page *start_page,
- struct buffer_head *head,
- struct buffer_head *curr,
- unsigned long p_offset,
- int block_bits,
- xfs_iomap_t *iomapp,
- struct writeback_control *wbc,
- int startio,
- int all_bh)
-{
- struct buffer_head *bh = curr;
- xfs_iomap_t *tmp;
- xfs_ioend_t *ioend;
- loff_t offset;
- unsigned long nblocks = 0;
-
- offset = start_page->index;
- offset <<= PAGE_CACHE_SHIFT;
- offset += p_offset;
-
- ioend = xfs_alloc_ioend(inode);
-
- /* First map forwards in the page consecutive buffers
- * covering this unwritten extent
- */
- do {
- if (!buffer_unwritten(bh))
- break;
- tmp = xfs_offset_to_map(start_page, iomapp, p_offset);
- if (!tmp)
- break;
- xfs_map_at_offset(start_page, bh, p_offset, block_bits, iomapp);
- set_buffer_unwritten_io(bh);
- bh->b_private = ioend;
- p_offset += bh->b_size;
- nblocks++;
- } while ((bh = bh->b_this_page) != head);
-
- atomic_add(nblocks, &ioend->io_remaining);
-
- /* If we reached the end of the page, map forwards in any
- * following pages which are also covered by this extent.
- */
- if (bh == head) {
- struct address_space *mapping = inode->i_mapping;
- pgoff_t tindex, tloff, tlast;
- unsigned long bs;
- unsigned int pg_offset, bbits = inode->i_blkbits;
- struct page *page;
-
- tlast = i_size_read(inode) >> PAGE_CACHE_SHIFT;
- tloff = (iomapp->iomap_offset + iomapp->iomap_bsize) >> PAGE_CACHE_SHIFT;
- tloff = min(tlast, tloff);
- for (tindex = start_page->index + 1; tindex < tloff; tindex++) {
- page = xfs_probe_unwritten_page(mapping,
- tindex, iomapp, ioend,
- PAGE_CACHE_SIZE, &bs, bbits);
- if (!page)
- break;
- nblocks += bs;
- atomic_add(bs, &ioend->io_remaining);
- xfs_convert_page(inode, page, iomapp, wbc, ioend,
- startio, all_bh);
- /* stop if converting the next page might add
- * enough blocks that the corresponding byte
- * count won't fit in our ulong page buf length */
- if (nblocks >= ((ULONG_MAX - PAGE_SIZE) >> block_bits))
- goto enough;
- }
-
- if (tindex == tlast &&
- (pg_offset = (i_size_read(inode) & (PAGE_CACHE_SIZE - 1)))) {
- page = xfs_probe_unwritten_page(mapping,
- tindex, iomapp, ioend,
- pg_offset, &bs, bbits);
- if (page) {
- nblocks += bs;
- atomic_add(bs, &ioend->io_remaining);
- xfs_convert_page(inode, page, iomapp, wbc, ioend,
- startio, all_bh);
- if (nblocks >= ((ULONG_MAX - PAGE_SIZE) >> block_bits))
- goto enough;
- }
- }
- }
-
-enough:
- ioend->io_size = (xfs_off_t)nblocks << block_bits;
- ioend->io_offset = offset;
- xfs_finish_ioend(ioend);
- return 0;
-}
-
-STATIC void
-xfs_submit_page(
- struct page *page,
- struct writeback_control *wbc,
- struct buffer_head *bh_arr[],
- int bh_count,
- int probed_page,
- int clear_dirty)
-{
- struct buffer_head *bh;
- int i;
-
- BUG_ON(PageWriteback(page));
- if (bh_count)
- set_page_writeback(page);
- if (clear_dirty)
- clear_page_dirty(page);
- unlock_page(page);
-
- if (bh_count) {
- for (i = 0; i < bh_count; i++) {
- bh = bh_arr[i];
- mark_buffer_async_write(bh);
- if (buffer_unwritten(bh))
- set_buffer_unwritten_io(bh);
- set_buffer_uptodate(bh);
- clear_buffer_dirty(bh);
- }
-
- for (i = 0; i < bh_count; i++)
- submit_bh(WRITE, bh_arr[i]);
-
- if (probed_page && clear_dirty)
- wbc->nr_to_write--; /* Wrote an "extra" page */
- }
-}
-
/*
* Allocate & map buffers for page given the extent map. Write it out.
* except for the original page of a writepage, this is called on
* delalloc/unwritten pages only, for the original page it is possible
* that the page has no mapping at all.
*/
-STATIC void
+STATIC int
xfs_convert_page(
struct inode *inode,
struct page *page,
xfs_iomap_t *iomapp,
+ xfs_ioend_t **ioendp,
struct writeback_control *wbc,
void *private,
int startio,
int all_bh)
{
- struct buffer_head *bh_arr[MAX_BUF_PER_PAGE], *bh, *head;
+ struct buffer_head *bh, *head;
xfs_iomap_t *mp = iomapp, *tmp;
- unsigned long offset, end_offset;
- int index = 0;
+ unsigned long p_offset, end_offset;
+ unsigned int type;
int bbits = inode->i_blkbits;
int len, page_dirty;
+ int count = 0, done = 0, uptodate = 1;
end_offset = (i_size_read(inode) & (PAGE_CACHE_SIZE - 1));
@@ -621,59 +655,66 @@
end_offset = roundup(end_offset, len);
page_dirty = end_offset / len;
- offset = 0;
+ p_offset = 0;
bh = head = page_buffers(page);
do {
- if (offset >= end_offset)
+ if (p_offset >= end_offset)
break;
- if (!(PageUptodate(page) || buffer_uptodate(bh)))
+ if (!buffer_uptodate(bh))
+ uptodate = 0;
+ if (!(PageUptodate(page) || buffer_uptodate(bh))) {
+ done = 1;
continue;
- if (buffer_mapped(bh) && all_bh &&
- !(buffer_unwritten(bh) || buffer_delay(bh))) {
- if (startio) {
+ }
+
+ if (buffer_unwritten(bh))
+ type = IOMAP_UNWRITTEN;
+ else if (buffer_delay(bh))
+ type = IOMAP_DELAY;
+ else {
+ type = 0;
+ if (!(buffer_mapped(bh) && all_bh && startio)) {
+ done = 1;
+ } else if (startio) {
lock_buffer(bh);
- bh_arr[index++] = bh;
+ xfs_add_to_ioend(inode, bh, p_offset,
+ type, ioendp, done);
+ count++;
page_dirty--;
}
continue;
}
- tmp = xfs_offset_to_map(page, mp, offset);
- if (!tmp)
+ tmp = xfs_offset_to_map(page, mp, p_offset);
+ if (!tmp) {
+ done = 1;
continue;
+ }
ASSERT(!(tmp->iomap_flags & IOMAP_HOLE));
ASSERT(!(tmp->iomap_flags & IOMAP_DELAY));
- /* If this is a new unwritten extent buffer (i.e. one
- * that we haven't passed in private data for, we must
- * now map this buffer too.
- */
- if (buffer_unwritten(bh) && !bh->b_end_io) {
- ASSERT(tmp->iomap_flags & IOMAP_UNWRITTEN);
- xfs_map_unwritten(inode, page, head, bh, offset,
- bbits, tmp, wbc, startio, all_bh);
- } else if (! (buffer_unwritten(bh) && buffer_locked(bh))) {
- xfs_map_at_offset(page, bh, offset, bbits, tmp);
- if (buffer_unwritten(bh)) {
- set_buffer_unwritten_io(bh);
- bh->b_private = private;
- ASSERT(private);
- }
- }
+ xfs_map_at_offset(page, bh, p_offset, bbits, tmp, *ioendp);
if (startio) {
- bh_arr[index++] = bh;
+ xfs_add_to_ioend(inode, bh, p_offset,
+ type, ioendp, done);
+ count++;
} else {
set_buffer_dirty(bh);
unlock_buffer(bh);
mark_buffer_dirty(bh);
}
page_dirty--;
- } while (offset += len, (bh = bh->b_this_page) != head);
+ } while (p_offset += len, (bh = bh->b_this_page) != head);
- if (startio && index) {
- xfs_submit_page(page, wbc, bh_arr, index, 1, !page_dirty);
- } else {
- unlock_page(page);
+ if (uptodate && bh == head)
+ SetPageUptodate(page);
+
+ if (startio) {
+ if (count)
+ wbc->nr_to_write--;
+ xfs_start_page_writeback(page, wbc, !page_dirty, count);
}
+
+ return done;
}
/*
@@ -685,19 +726,22 @@
struct inode *inode,
pgoff_t tindex,
xfs_iomap_t *iomapp,
+ xfs_ioend_t **ioendp,
struct writeback_control *wbc,
int startio,
int all_bh,
pgoff_t tlast)
{
struct page *page;
+ unsigned int type = (*ioendp)->io_type;
+ int done;
- for (; tindex <= tlast; tindex++) {
- page = xfs_probe_delalloc_page(inode, tindex);
+ for (done = 0; tindex <= tlast && !done; tindex++) {
+ page = xfs_probe_delayed_page(inode, tindex, type);
if (!page)
break;
- xfs_convert_page(inode, page, iomapp, wbc, NULL,
- startio, all_bh);
+ done = xfs_convert_page(inode, page, iomapp, ioendp,
+ wbc, NULL, startio, all_bh);
}
}
@@ -728,18 +772,21 @@
int startio,
int unmapped) /* also implies page uptodate */
{
- struct buffer_head *bh_arr[MAX_BUF_PER_PAGE], *bh, *head;
+ struct buffer_head *bh, *head;
xfs_iomap_t *iomp, iomap;
+ xfs_ioend_t *ioend = NULL, *iohead = NULL;
loff_t offset;
unsigned long p_offset = 0;
+ unsigned int type;
__uint64_t end_offset;
pgoff_t end_index, last_index, tlast;
- int len, err, i, cnt = 0, uptodate = 1;
- int flags;
- int page_dirty;
+ int flags, len, err, done = 1;
+ int uptodate = 1;
+ int page_dirty, count = 0, trylock_flag = 0;
/* wait for other IO threads? */
- flags = (startio && wbc->sync_mode != WB_SYNC_NONE) ? 0 : BMAPI_TRYLOCK;
+ if (startio && wbc->sync_mode != WB_SYNC_NONE)
+ trylock_flag |= BMAPI_TRYLOCK;
/* Is this page beyond the end of the file? */
offset = i_size_read(inode);
@@ -754,98 +801,98 @@
}
}
- end_offset = min_t(unsigned long long,
- (loff_t)(page->index + 1) << PAGE_CACHE_SHIFT, offset);
- offset = (loff_t)page->index << PAGE_CACHE_SHIFT;
-
/*
* page_dirty is initially a count of buffers on the page before
* EOF and is decrememted as we move each into a cleanable state.
- */
+ *
+ * Derivation:
+ *
+ * End offset is the highest offset that this page should represent.
+ * If we are on the last page, (end_offset & (PAGE_CACHE_SIZE - 1))
+ * will evaluate non-zero and be less than PAGE_CACHE_SIZE and
+ * hence give us the correct page_dirty count. On any other page,
+ * it will be zero and in that case we need page_dirty to be the
+ * count of buffers on the page.
+ */
+ end_offset = min_t(unsigned long long,
+ (xfs_off_t)(page->index + 1) << PAGE_CACHE_SHIFT, offset);
len = 1 << inode->i_blkbits;
- p_offset = max(p_offset, PAGE_CACHE_SIZE);
- p_offset = roundup(p_offset, len);
+ p_offset = min_t(unsigned long, end_offset & (PAGE_CACHE_SIZE - 1),
+ PAGE_CACHE_SIZE);
+ p_offset = p_offset ? roundup(p_offset, len) : PAGE_CACHE_SIZE;
page_dirty = p_offset / len;
iomp = NULL;
- p_offset = 0;
bh = head = page_buffers(page);
+ offset = page_offset(page);
+
+ /* TODO: fix up "done" variable and iomap pointer (boolean) */
+ /* TODO: cleanup count and page_dirty */
do {
if (offset >= end_offset)
break;
if (!buffer_uptodate(bh))
uptodate = 0;
- if (!(PageUptodate(page) || buffer_uptodate(bh)) && !startio)
+ if (!(PageUptodate(page) || buffer_uptodate(bh)) && !startio) {
+ done = 1;
continue;
+ }
if (iomp) {
iomp = xfs_offset_to_map(page, &iomap, p_offset);
+ done = (iomp == NULL);
}
/*
* First case, map an unwritten extent and prepare for
* extent state conversion transaction on completion.
- */
- if (buffer_unwritten(bh)) {
- if (!startio)
- continue;
- if (!iomp) {
- err = xfs_map_blocks(inode, offset, len, &iomap,
- BMAPI_WRITE|BMAPI_IGNSTATE);
- if (err) {
- goto error;
- }
- iomp = xfs_offset_to_map(page, &iomap,
- p_offset);
- }
- if (iomp) {
- if (!bh->b_end_io) {
- err = xfs_map_unwritten(inode, page,
- head, bh, p_offset,
- inode->i_blkbits, iomp,
- wbc, startio, unmapped);
- if (err) {
- goto error;
- }
- } else {
- set_bit(BH_Lock, &bh->b_state);
- }
- BUG_ON(!buffer_locked(bh));
- bh_arr[cnt++] = bh;
- page_dirty--;
- }
- /*
+ *
* Second case, allocate space for a delalloc buffer.
* We can return EAGAIN here in the release page case.
*/
- } else if (buffer_delay(bh)) {
+ if (buffer_unwritten(bh) || buffer_delay(bh)) {
+ if (buffer_unwritten(bh)) {
+ type = IOMAP_UNWRITTEN;
+ flags = BMAPI_WRITE|BMAPI_IGNSTATE;
+ } else {
+ type = IOMAP_DELAY;
+ flags = BMAPI_ALLOCATE;
+ if (!startio)
+ flags |= trylock_flag;
+ }
+
if (!iomp) {
+ done = 1;
err = xfs_map_blocks(inode, offset, len, &iomap,
- BMAPI_ALLOCATE | flags);
- if (err) {
+ flags);
+ if (err)
goto error;
- }
iomp = xfs_offset_to_map(page, &iomap,
p_offset);
+ done = (iomp == NULL);
}
if (iomp) {
xfs_map_at_offset(page, bh, p_offset,
- inode->i_blkbits, iomp);
+ inode->i_blkbits, iomp, ioend);
if (startio) {
- bh_arr[cnt++] = bh;
+ xfs_add_to_ioend(inode, bh, p_offset,
+ type, &ioend, done);
} else {
set_buffer_dirty(bh);
unlock_buffer(bh);
mark_buffer_dirty(bh);
}
page_dirty--;
+ count++;
+ } else {
+ done = 1;
}
} else if ((buffer_uptodate(bh) || PageUptodate(page)) &&
(unmapped || startio)) {
+ type = 0;
if (!buffer_mapped(bh)) {
- int size;
/*
* Getting here implies an unmapped buffer
@@ -853,6 +900,8 @@
* need to write the whole page out.
*/
if (!iomp) {
+ int size;
+
size = xfs_probe_unmapped_cluster(
inode, page, bh, head);
err = xfs_map_blocks(inode, offset,
@@ -863,52 +912,70 @@
}
iomp = xfs_offset_to_map(page, &iomap,
p_offset);
+ done = (iomp == NULL);
}
if (iomp) {
- xfs_map_at_offset(page,
- bh, p_offset,
- inode->i_blkbits, iomp);
+ xfs_map_at_offset(page, bh, p_offset,
+ inode->i_blkbits, iomp,
+ ioend);
if (startio) {
- bh_arr[cnt++] = bh;
+ xfs_add_to_ioend(inode,
+ bh, p_offset, type,
+ &ioend, done);
} else {
set_buffer_dirty(bh);
unlock_buffer(bh);
mark_buffer_dirty(bh);
}
page_dirty--;
+ count++;
+ } else {
+ done = 1;
}
} else if (startio) {
if (buffer_uptodate(bh) &&
!test_and_set_bit(BH_Lock, &bh->b_state)) {
- bh_arr[cnt++] = bh;
+ ASSERT(buffer_mapped(bh));
+ xfs_add_to_ioend(inode,
+ bh, p_offset, type,
+ &ioend, done);
page_dirty--;
+ count++;
+ } else {
+ done = 1;
}
+ } else {
+ done = 1;
}
}
- } while (offset += len, p_offset += len,
- ((bh = bh->b_this_page) != head));
+
+ if (!iohead)
+ iohead = ioend;
+
+ } while (offset += len, ((bh = bh->b_this_page) != head));
if (uptodate && bh == head)
SetPageUptodate(page);
- if (startio) {
- xfs_submit_page(page, wbc, bh_arr, cnt, 0, !page_dirty);
- }
+ if (startio)
+ xfs_start_page_writeback(page, wbc, 1, count);
- if (iomp) {
+ if (ioend && iomp && !done) {
offset = (iomp->iomap_offset + iomp->iomap_bsize - 1) >>
PAGE_CACHE_SHIFT;
tlast = min_t(pgoff_t, offset, last_index);
- xfs_cluster_write(inode, page->index + 1, iomp, wbc,
- startio, unmapped, tlast);
+ xfs_cluster_write(inode, page->index + 1, iomp, &ioend,
+ wbc, startio, unmapped, tlast);
}
+ if (iohead)
+ xfs_submit_ioend(iohead);
+
return page_dirty;
error:
- for (i = 0; i < cnt; i++) {
- unlock_buffer(bh_arr[i]);
- }
+ if (iohead)
+ xfs_cancel_ioend(iohead);
/*
* If it's delalloc and we have nowhere to put it,
@@ -916,9 +983,8 @@
* us to try again.
*/
if (err != -EAGAIN) {
- if (!unmapped) {
+ if (!unmapped)
block_invalidatepage(page, 0);
- }
ClearPageUptodate(page);
}
return err;
@@ -1094,7 +1160,7 @@
if (error)
return -error;
- iocb->private = xfs_alloc_ioend(inode);
+ iocb->private = xfs_alloc_ioend(inode, IOMAP_UNWRITTEN);
ret = blockdev_direct_IO_own_locking(rw, iocb, inode,
iomap.iomap_target->bt_bdev,
