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-rw-r--r--fs/xfs/linux-2.6/xfs_aops.c354
1 files changed, 107 insertions, 247 deletions
diff --git a/fs/xfs/linux-2.6/xfs_aops.c b/fs/xfs/linux-2.6/xfs_aops.c
index bd5e1cf5428d..7744a3b630e0 100644
--- a/fs/xfs/linux-2.6/xfs_aops.c
+++ b/fs/xfs/linux-2.6/xfs_aops.c
@@ -754,7 +754,6 @@ xfs_convert_page(
struct xfs_bmbt_irec *imap,
xfs_ioend_t **ioendp,
struct writeback_control *wbc,
- int startio,
int all_bh)
{
struct buffer_head *bh, *head;
@@ -825,19 +824,14 @@ xfs_convert_page(
ASSERT(imap->br_startblock != DELAYSTARTBLOCK);
xfs_map_at_offset(inode, bh, imap, offset);
- if (startio) {
- xfs_add_to_ioend(inode, bh, offset,
- type, ioendp, done);
- } else {
- set_buffer_dirty(bh);
- unlock_buffer(bh);
- mark_buffer_dirty(bh);
- }
+ xfs_add_to_ioend(inode, bh, offset, type,
+ ioendp, done);
+
page_dirty--;
count++;
} else {
type = IO_NEW;
- if (buffer_mapped(bh) && all_bh && startio) {
+ if (buffer_mapped(bh) && all_bh) {
lock_buffer(bh);
xfs_add_to_ioend(inode, bh, offset,
type, ioendp, done);
@@ -852,14 +846,12 @@ xfs_convert_page(
if (uptodate && bh == head)
SetPageUptodate(page);
- if (startio) {
- if (count) {
- wbc->nr_to_write--;
- if (wbc->nr_to_write <= 0)
- done = 1;
- }
- xfs_start_page_writeback(page, !page_dirty, count);
+ if (count) {
+ wbc->nr_to_write--;
+ if (wbc->nr_to_write <= 0)
+ done = 1;
}
+ xfs_start_page_writeback(page, !page_dirty, count);
return done;
fail_unlock_page:
@@ -879,7 +871,6 @@ xfs_cluster_write(
struct xfs_bmbt_irec *imap,
xfs_ioend_t **ioendp,
struct writeback_control *wbc,
- int startio,
int all_bh,
pgoff_t tlast)
{
@@ -895,7 +886,7 @@ xfs_cluster_write(
for (i = 0; i < pagevec_count(&pvec); i++) {
done = xfs_convert_page(inode, pvec.pages[i], tindex++,
- imap, ioendp, wbc, startio, all_bh);
+ imap, ioendp, wbc, all_bh);
if (done)
break;
}
@@ -1025,51 +1016,94 @@ out_invalidate:
}
/*
- * Calling this without startio set means we are being asked to make a dirty
- * page ready for freeing it's buffers. When called with startio set then
- * we are coming from writepage.
+ * 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.
+ * For unmapped buffer heads on the page we should allocate space if the
+ * page is uptodate.
+ * For any other dirty buffer heads on the page we should flush them.
*
- * When called with startio set it is important that we write the WHOLE
- * page if possible.
- * The bh->b_state's cannot know if any of the blocks or which block for
- * that matter are dirty due to mmap writes, and therefore bh uptodate is
- * only valid if the page itself isn't completely uptodate. Some layers
- * may clear the page dirty flag prior to calling write page, under the
- * assumption the entire page will be written out; by not writing out the
- * whole page the page can be reused before all valid dirty data is
- * written out. Note: in the case of a page that has been dirty'd by
- * mapwrite and but partially setup by block_prepare_write the
- * bh->b_states's will not agree and only ones setup by BPW/BCW will have
- * valid state, thus the whole page must be written out thing.
+ * If we detect that a transaction would be required to flush the page, we
+ * have to check the process flags first, if we are already in a transaction
+ * or disk I/O during allocations is off, we need to fail the writepage and
+ * redirty the page.
+ *
+ * The bh->b_state's cannot know if any of the blocks or which block for that
+ * matter are dirty due to mmap writes, and therefore bh uptodate is only
+ * valid if the page itself isn't completely uptodate.
*/
-
STATIC int
-xfs_page_state_convert(
- struct inode *inode,
- struct page *page,
- struct writeback_control *wbc,
- int startio,
- int unmapped) /* also implies page uptodate */
+xfs_vm_writepage(
+ struct page *page,
+ struct writeback_control *wbc)
{
+ struct inode *inode = page->mapping->host;
+ int need_trans;
+ int delalloc, unmapped, unwritten;
struct buffer_head *bh, *head;
struct xfs_bmbt_irec imap;
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;
ssize_t size, len;
int flags, err, imap_valid = 0, uptodate = 1;
- int page_dirty, count = 0;
- int trylock = 0;
- int all_bh = unmapped;
+ int count = 0;
+ int all_bh;
+
+ trace_xfs_writepage(inode, page, 0);
+
+ /*
+ * Refuse to write the page out if we are called from reclaim context.
+ *
+ * This is primarily to avoid stack overflows when called from deep
+ * used stacks in random callers for direct reclaim, but disabling
+ * reclaim for kswap is a nice side-effect as kswapd causes rather
+ * suboptimal I/O patters, too.
+ *
+ * This should really be done by the core VM, but until that happens
+ * filesystems like XFS, btrfs and ext4 have to take care of this
+ * by themselves.
+ */
+ if (current->flags & PF_MEMALLOC)
+ goto out_fail;
- if (startio) {
- if (wbc->sync_mode == WB_SYNC_NONE && wbc->nonblocking)
- trylock |= BMAPI_TRYLOCK;
+ /*
+ * We need a transaction if:
+ * 1. There are delalloc buffers on the page
+ * 2. The page is uptodate and we have unmapped buffers
+ * 3. The page is uptodate and we have no buffers
+ * 4. There are unwritten buffers on the page
+ */
+ if (!page_has_buffers(page)) {
+ unmapped = 1;
+ need_trans = 1;
+ } else {
+ xfs_count_page_state(page, &delalloc, &unmapped, &unwritten);
+ if (!PageUptodate(page))
+ unmapped = 0;
+ need_trans = delalloc + unmapped + unwritten;
}
+ /*
+ * If we need a transaction and the process flags say
+ * we are already in a transaction, or no IO is allowed
+ * then mark the page dirty again and leave the page
+ * as is.
+ */
+ if (current_test_flags(PF_FSTRANS) && need_trans)
+ goto out_fail;
+
+ /*
+ * Delay hooking up buffer heads until we have
+ * made our go/no-go decision.
+ */
+ if (!page_has_buffers(page))
+ create_empty_buffers(page, 1 << inode->i_blkbits, 0);
+
/* Is this page beyond the end of the file? */
offset = i_size_read(inode);
end_index = offset >> PAGE_CACHE_SHIFT;
@@ -1077,53 +1111,27 @@ xfs_page_state_convert(
if (page->index >= end_index) {
if ((page->index >= end_index + 1) ||
!(i_size_read(inode) & (PAGE_CACHE_SIZE - 1))) {
- if (startio)
- unlock_page(page);
+ unlock_page(page);
return 0;
}
}
- /*
- * page_dirty is initially a count of buffers on the page before
- * EOF and is decremented 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 = 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;
bh = head = page_buffers(page);
offset = page_offset(page);
flags = BMAPI_READ;
type = IO_NEW;
- /* TODO: cleanup count and page_dirty */
+ all_bh = unmapped;
do {
if (offset >= end_offset)
break;
if (!buffer_uptodate(bh))
uptodate = 0;
- if (!(PageUptodate(page) || buffer_uptodate(bh)) && !startio) {
- /*
- * the iomap is actually still valid, but the ioend
- * isn't. shouldn't happen too often.
- */
- imap_valid = 0;
- continue;
- }
/*
* A hole may still be marked uptodate because discard_buffer
@@ -1150,7 +1158,7 @@ xfs_page_state_convert(
*/
if (buffer_unwritten(bh) || buffer_delay(bh) ||
((buffer_uptodate(bh) || PageUptodate(page)) &&
- !buffer_mapped(bh) && (unmapped || startio))) {
+ !buffer_mapped(bh))) {
int new_ioend = 0;
/*
@@ -1164,7 +1172,11 @@ xfs_page_state_convert(
flags = BMAPI_WRITE | BMAPI_IGNSTATE;
} else if (buffer_delay(bh)) {
type = IO_DELAY;
- flags = BMAPI_ALLOCATE | trylock;
+ flags = BMAPI_ALLOCATE;
+
+ if (wbc->sync_mode == WB_SYNC_NONE &&
+ wbc->nonblocking)
+ flags |= BMAPI_TRYLOCK;
} else {
type = IO_NEW;
flags = BMAPI_WRITE | BMAPI_MMAP;
@@ -1196,19 +1208,11 @@ xfs_page_state_convert(
}
if (imap_valid) {
xfs_map_at_offset(inode, bh, &imap, offset);
- if (startio) {
- xfs_add_to_ioend(inode, bh, offset,
- type, &ioend,
- new_ioend);
- } else {
- set_buffer_dirty(bh);
- unlock_buffer(bh);
- mark_buffer_dirty(bh);
- }
- page_dirty--;
+ xfs_add_to_ioend(inode, bh, offset, type,
+ &ioend, new_ioend);
count++;
}
- } else if (buffer_uptodate(bh) && startio) {
+ } else if (buffer_uptodate(bh)) {
/*
* we got here because the buffer is already mapped.
* That means it must already have extents allocated
@@ -1241,13 +1245,11 @@ xfs_page_state_convert(
all_bh = 1;
xfs_add_to_ioend(inode, bh, offset, type,
&ioend, !imap_valid);
- page_dirty--;
count++;
} else {
imap_valid = 0;
}
- } else if ((buffer_uptodate(bh) || PageUptodate(page)) &&
- (unmapped || startio)) {
+ } else if (PageUptodate(page)) {
imap_valid = 0;
}
@@ -1259,8 +1261,7 @@ xfs_page_state_convert(
if (uptodate && bh == head)
SetPageUptodate(page);
- if (startio)
- xfs_start_page_writeback(page, 1, count);
+ xfs_start_page_writeback(page, 1, count);
if (ioend && imap_valid) {
xfs_off_t end_index;
@@ -1278,131 +1279,28 @@ xfs_page_state_convert(
end_index = last_index;
xfs_cluster_write(inode, page->index + 1, &imap, &ioend,
- wbc, startio, all_bh, end_index);
+ wbc, all_bh, end_index);
}
if (iohead)
xfs_submit_ioend(wbc, iohead);
- return page_dirty;
+ return 0;
error:
if (iohead)
xfs_cancel_ioend(iohead);
- /*
- * If it's delalloc and we have nowhere to put it,
- * throw it away, unless the lower layers told
- * us to try again.
- */
- if (err != -EAGAIN) {
- if (!unmapped)
- xfs_aops_discard_page(page);
- ClearPageUptodate(page);
- }
+ if (!unmapped)
+ xfs_aops_discard_page(page);
+ ClearPageUptodate(page);
+ unlock_page(page);
return err;
-}
-
-/*
- * writepage: Called from one of two places:
- *
- * 1. we are flushing a delalloc buffer head.
- *
- * 2. we are writing out a dirty page. Typically the page dirty
- * state is cleared before we get here. In this case is it
- * conceivable we have no buffer heads.
- *
- * For delalloc space on the page we need to allocate space and
- * flush it. For unmapped buffer heads on the page we should
- * allocate space if the page is uptodate. For any other dirty
- * buffer heads on the page we should flush them.
- *
- * If we detect that a transaction would be required to flush
- * the page, we have to check the process flags first, if we
- * are already in a transaction or disk I/O during allocations
- * is off, we need to fail the writepage and redirty the page.
- */
-
-STATIC int
-xfs_vm_writepage(
- struct page *page,
- struct writeback_control *wbc)
-{
- int error;
- int need_trans;
- int delalloc, unmapped, unwritten;
- struct inode *inode = page->mapping->host;
-
- trace_xfs_writepage(inode, page, 0);
-
- /*
- * Refuse to write the page out if we are called from reclaim context.
- *
- * This is primarily to avoid stack overflows when called from deep
- * used stacks in random callers for direct reclaim, but disabling
- * reclaim for kswap is a nice side-effect as kswapd causes rather
- * suboptimal I/O patters, too.
- *
- * This should really be done by the core VM, but until that happens
- * filesystems like XFS, btrfs and ext4 have to take care of this
- * by themselves.
- */
- if (current->flags & PF_MEMALLOC)
- goto out_fail;
-
- /*
- * We need a transaction if:
- * 1. There are delalloc buffers on the page
- * 2. The page is uptodate and we have unmapped buffers
- * 3. The page is uptodate and we have no buffers
- * 4. There are unwritten buffers on the page
- */
-
- if (!page_has_buffers(page)) {
- unmapped = 1;
- need_trans = 1;
- } else {
- xfs_count_page_state(page, &delalloc, &unmapped, &unwritten);
- if (!PageUptodate(page))
- unmapped = 0;
- need_trans = delalloc + unmapped + unwritten;
- }
-
- /*
- * If we need a transaction and the process flags say
- * we are already in a transaction, or no IO is allowed
- * then mark the page dirty again and leave the page
- * as is.
- */
- if (current_test_flags(PF_FSTRANS) && need_trans)
- goto out_fail;
-
- /*
- * Delay hooking up buffer heads until we have
- * made our go/no-go decision.
- */
- if (!page_has_buffers(page))
- create_empty_buffers(page, 1 << inode->i_blkbits, 0);
-
- /*
- * Convert delayed allocate, unwritten or unmapped space
- * to real space and flush out to disk.
- */
- error = xfs_page_state_convert(inode, page, wbc, 1, unmapped);
- if (error == -EAGAIN)
- goto out_fail;
- if (unlikely(error < 0))
- goto out_unlock;
-
- return 0;
out_fail:
redirty_page_for_writepage(wbc, page);
unlock_page(page);
return 0;
-out_unlock:
- unlock_page(page);
- return error;
}
STATIC int
@@ -1416,65 +1314,27 @@ xfs_vm_writepages(
/*
* Called to move a page into cleanable state - and from there
- * to be released. Possibly the page is already clean. We always
+ * to be released. The page should already be clean. We always
* have buffer heads in this call.
*
- * Returns 0 if the page is ok to release, 1 otherwise.
- *
- * Possible scenarios are:
- *
- * 1. We are being called to release a page which has been written
- * to via regular I/O. buffer heads will be dirty and possibly
- * delalloc. If no delalloc buffer heads in this case then we
- * can just return zero.
- *
- * 2. We are called to release a page which has been written via
- * mmap, all we need to do is ensure there is no delalloc
- * state in the buffer heads, if not we can let the caller
- * free them and we should come back later via writepage.
+ * Returns 1 if the page is ok to release, 0 otherwise.
*/
STATIC int
xfs_vm_releasepage(
struct page *page,
gfp_t gfp_mask)
{
- struct inode *inode = page->mapping->host;
- int dirty, delalloc, unmapped, unwritten;
- struct writeback_control wbc = {
- .sync_mode = WB_SYNC_ALL,
- .nr_to_write = 1,
- };
-
- trace_xfs_releasepage(inode, page, 0);
+ int delalloc, unmapped, unwritten;
- if (!page_has_buffers(page))
- return 0;
+ trace_xfs_releasepage(page->mapping->host, page, 0);
xfs_count_page_state(page, &delalloc, &unmapped, &unwritten);
- if (!delalloc && !unwritten)
- goto free_buffers;
- if (!(gfp_mask & __GFP_FS))
+ if (WARN_ON(delalloc))
return 0;
-
- /* If we are already inside a transaction or the thread cannot
- * do I/O, we cannot release this page.
- */
- if (current_test_flags(PF_FSTRANS))
+ if (WARN_ON(unwritten))
return 0;
- /*
- * Convert delalloc space to real space, do not flush the
- * data out to disk, that will be done by the caller.
- * Never need to allocate space here - we will always
- * come back to writepage in that case.
- */
- dirty = xfs_page_state_convert(inode, page, &wbc, 0, 0);
- if (dirty == 0 && !unwritten)
- goto free_buffers;
- return 0;
-
-free_buffers:
return try_to_free_buffers(page);
}
generated by cgit v1.2.3 (git 2.39.1) at 2024-11-29 22:46:29 +0000