aboutsummaryrefslogtreecommitdiffstats
path: root/fs/xfs/linux-2.6/xfs_aops.c
diff options
context:
space:
mode:
Diffstat (limited to 'fs/xfs/linux-2.6/xfs_aops.c')
-rw-r--r--fs/xfs/linux-2.6/xfs_aops.c645
1 files changed, 251 insertions, 394 deletions
diff --git a/fs/xfs/linux-2.6/xfs_aops.c b/fs/xfs/linux-2.6/xfs_aops.c
index 34640d6dbdcb..15412fe15c3a 100644
--- a/fs/xfs/linux-2.6/xfs_aops.c
+++ b/fs/xfs/linux-2.6/xfs_aops.c
@@ -21,19 +21,12 @@
#include "xfs_inum.h"
#include "xfs_sb.h"
#include "xfs_ag.h"
-#include "xfs_dir2.h"
#include "xfs_trans.h"
-#include "xfs_dmapi.h"
#include "xfs_mount.h"
#include "xfs_bmap_btree.h"
-#include "xfs_alloc_btree.h"
-#include "xfs_ialloc_btree.h"
-#include "xfs_dir2_sf.h"
-#include "xfs_attr_sf.h"
#include "xfs_dinode.h"
#include "xfs_inode.h"
#include "xfs_alloc.h"
-#include "xfs_btree.h"
#include "xfs_error.h"
#include "xfs_rw.h"
#include "xfs_iomap.h"
@@ -92,18 +85,15 @@ void
xfs_count_page_state(
struct page *page,
int *delalloc,
- int *unmapped,
int *unwritten)
{
struct buffer_head *bh, *head;
- *delalloc = *unmapped = *unwritten = 0;
+ *delalloc = *unwritten = 0;
bh = head = page_buffers(page);
do {
- if (buffer_uptodate(bh) && !buffer_mapped(bh))
- (*unmapped) = 1;
- else if (buffer_unwritten(bh))
+ if (buffer_unwritten(bh))
(*unwritten) = 1;
else if (buffer_delay(bh))
(*delalloc) = 1;
@@ -212,23 +202,17 @@ xfs_setfilesize(
}
/*
- * Schedule IO completion handling on a xfsdatad if this was
- * the final hold on this ioend. If we are asked to wait,
- * flush the workqueue.
+ * Schedule IO completion handling on the final put of an ioend.
*/
STATIC void
xfs_finish_ioend(
- xfs_ioend_t *ioend,
- int wait)
+ struct xfs_ioend *ioend)
{
if (atomic_dec_and_test(&ioend->io_remaining)) {
- struct workqueue_struct *wq;
-
- wq = (ioend->io_type == IO_UNWRITTEN) ?
- xfsconvertd_workqueue : xfsdatad_workqueue;
- queue_work(wq, &ioend->io_work);
- if (wait)
- flush_workqueue(wq);
+ if (ioend->io_type == IO_UNWRITTEN)
+ queue_work(xfsconvertd_workqueue, &ioend->io_work);
+ else
+ queue_work(xfsdatad_workqueue, &ioend->io_work);
}
}
@@ -272,11 +256,25 @@ xfs_end_io(
*/
if (error == EAGAIN) {
atomic_inc(&ioend->io_remaining);
- xfs_finish_ioend(ioend, 0);
+ xfs_finish_ioend(ioend);
/* ensure we don't spin on blocked ioends */
delay(1);
- } else
+ } else {
+ if (ioend->io_iocb)
+ aio_complete(ioend->io_iocb, ioend->io_result, 0);
xfs_destroy_ioend(ioend);
+ }
+}
+
+/*
+ * Call IO completion handling in caller context on the final put of an ioend.
+ */
+STATIC void
+xfs_finish_ioend_sync(
+ struct xfs_ioend *ioend)
+{
+ if (atomic_dec_and_test(&ioend->io_remaining))
+ xfs_end_io(&ioend->io_work);
}
/*
@@ -309,6 +307,8 @@ xfs_alloc_ioend(
atomic_inc(&XFS_I(ioend->io_inode)->i_iocount);
ioend->io_offset = 0;
ioend->io_size = 0;
+ ioend->io_iocb = NULL;
+ ioend->io_result = 0;
INIT_WORK(&ioend->io_work, xfs_end_io);
return ioend;
@@ -358,7 +358,7 @@ xfs_end_bio(
bio->bi_end_io = NULL;
bio_put(bio);
- xfs_finish_ioend(ioend, 0);
+ xfs_finish_ioend(ioend);
}
STATIC void
@@ -500,7 +500,7 @@ xfs_submit_ioend(
}
if (bio)
xfs_submit_ioend_bio(wbc, ioend, bio);
- xfs_finish_ioend(ioend, 0);
+ xfs_finish_ioend(ioend);
} while ((ioend = next) != NULL);
}
@@ -614,31 +614,30 @@ xfs_map_at_offset(
STATIC unsigned int
xfs_probe_page(
struct page *page,
- unsigned int pg_offset,
- int mapped)
+ unsigned int pg_offset)
{
+ struct buffer_head *bh, *head;
int ret = 0;
if (PageWriteback(page))
return 0;
+ if (!PageDirty(page))
+ return 0;
+ if (!page->mapping)
+ return 0;
+ if (!page_has_buffers(page))
+ return 0;
- if (page->mapping && PageDirty(page)) {
- if (page_has_buffers(page)) {
- struct buffer_head *bh, *head;
-
- bh = head = page_buffers(page);
- do {
- if (!buffer_uptodate(bh))
- break;
- if (mapped != buffer_mapped(bh))
- break;
- ret += bh->b_size;
- if (ret >= pg_offset)
- break;
- } while ((bh = bh->b_this_page) != head);
- } else
- ret = mapped ? 0 : PAGE_CACHE_SIZE;
- }
+ bh = head = page_buffers(page);
+ do {
+ if (!buffer_uptodate(bh))
+ break;
+ if (!buffer_mapped(bh))
+ break;
+ ret += bh->b_size;
+ if (ret >= pg_offset)
+ break;
+ } while ((bh = bh->b_this_page) != head);
return ret;
}
@@ -648,8 +647,7 @@ xfs_probe_cluster(
struct inode *inode,
struct page *startpage,
struct buffer_head *bh,
- struct buffer_head *head,
- int mapped)
+ struct buffer_head *head)
{
struct pagevec pvec;
pgoff_t tindex, tlast, tloff;
@@ -658,7 +656,7 @@ xfs_probe_cluster(
/* First sum forwards in this page */
do {
- if (!buffer_uptodate(bh) || (mapped != buffer_mapped(bh)))
+ if (!buffer_uptodate(bh) || !buffer_mapped(bh))
return total;
total += bh->b_size;
} while ((bh = bh->b_this_page) != head);
@@ -692,7 +690,7 @@ xfs_probe_cluster(
pg_offset = PAGE_CACHE_SIZE;
if (page->index == tindex && trylock_page(page)) {
- pg_len = xfs_probe_page(page, pg_offset, mapped);
+ pg_len = xfs_probe_page(page, pg_offset);
unlock_page(page);
}
@@ -761,7 +759,6 @@ 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;
@@ -832,19 +829,14 @@ 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);
@@ -859,14 +851,12 @@ 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:
@@ -886,7 +876,6 @@ xfs_cluster_write(
struct xfs_bmbt_irec *imap,
xfs_ioend_t **ioendp,
struct writeback_control *wbc,
- int startio,
int all_bh,
pgoff_t tlast)
{
@@ -902,7 +891,7 @@ 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;
}
@@ -981,7 +970,7 @@ xfs_aops_discard_page(
*/
error = xfs_bmapi(NULL, ip, offset_fsb, 1,
XFS_BMAPI_ENTIRE, NULL, 0, &imap,
- &nimaps, NULL, NULL);
+ &nimaps, NULL);
if (error) {
/* something screwed, just bail */
@@ -1009,7 +998,7 @@ xfs_aops_discard_page(
*/
xfs_bmap_init(&flist, &firstblock);
error = xfs_bunmapi(NULL, ip, offset_fsb, 1, 0, 1, &firstblock,
- &flist, NULL, &done);
+ &flist, &done);
ASSERT(!flist.xbf_count && !flist.xbf_first);
if (error) {
@@ -1032,50 +1021,66 @@ 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.
*
- * 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.
+ * 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 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_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 delalloc, 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 = 0;
- if (startio) {
- if (wbc->sync_mode == WB_SYNC_NONE && wbc->nonblocking)
- trylock |= BMAPI_TRYLOCK;
- }
+ trace_xfs_writepage(inode, page, 0);
+
+ ASSERT(page_has_buffers(page));
+
+ /*
+ * 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 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|PF_KSWAPD)) == PF_MEMALLOC)
+ goto out_fail;
+
+ /*
+ * We need a transaction if there are delalloc or unwritten buffers
+ * on the page.
+ *
+ * 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.
+ */
+ xfs_count_page_state(page, &delalloc, &unwritten);
+ if ((current->flags & PF_FSTRANS) && (delalloc || unwritten))
+ goto out_fail;
/* Is this page beyond the end of the file? */
offset = i_size_read(inode);
@@ -1084,50 +1089,33 @@ 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);
+ (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 */
-
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.
- */
+
+ /*
+ * A hole may still be marked uptodate because discard_buffer
+ * leaves the flag set.
+ */
+ if (!buffer_mapped(bh) && buffer_uptodate(bh)) {
+ ASSERT(!buffer_dirty(bh));
imap_valid = 0;
continue;
}
@@ -1135,19 +1123,7 @@ xfs_page_state_convert(
if (imap_valid)
imap_valid = xfs_imap_valid(inode, &imap, offset);
- /*
- * First case, map an unwritten extent and prepare for
- * extent state conversion transaction on completion.
- *
- * Second case, allocate space for a delalloc buffer.
- * We can return EAGAIN here in the release page case.
- *
- * Third case, an unmapped buffer was found, and we are
- * in a path where we need to write the whole page out.
- */
- if (buffer_unwritten(bh) || buffer_delay(bh) ||
- ((buffer_uptodate(bh) || PageUptodate(page)) &&
- !buffer_mapped(bh) && (unmapped || startio))) {
+ if (buffer_unwritten(bh) || buffer_delay(bh)) {
int new_ioend = 0;
/*
@@ -1161,15 +1137,16 @@ xfs_page_state_convert(
flags = BMAPI_WRITE | BMAPI_IGNSTATE;
} else if (buffer_delay(bh)) {
type = IO_DELAY;
- flags = BMAPI_ALLOCATE | trylock;
- } else {
- type = IO_NEW;
- flags = BMAPI_WRITE | BMAPI_MMAP;
+ flags = BMAPI_ALLOCATE;
+
+ if (wbc->sync_mode == WB_SYNC_NONE &&
+ wbc->nonblocking)
+ flags |= BMAPI_TRYLOCK;
}
if (!imap_valid) {
/*
- * if we didn't have a valid mapping then we
+ * If we didn't have a valid mapping then we
* need to ensure that we put the new mapping
* in a new ioend structure. This needs to be
* done to ensure that the ioends correctly
@@ -1177,14 +1154,7 @@ xfs_page_state_convert(
* for unwritten extent conversion.
*/
new_ioend = 1;
- if (type == IO_NEW) {
- size = xfs_probe_cluster(inode,
- page, bh, head, 0);
- } else {
- size = len;
- }
-
- err = xfs_map_blocks(inode, offset, size,
+ err = xfs_map_blocks(inode, offset, len,
&imap, flags);
if (err)
goto error;
@@ -1193,19 +1163,11 @@ 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
@@ -1213,8 +1175,7 @@ xfs_page_state_convert(
*/
if (!imap_valid || flags != BMAPI_READ) {
flags = BMAPI_READ;
- size = xfs_probe_cluster(inode, page, bh,
- head, 1);
+ size = xfs_probe_cluster(inode, page, bh, head);
err = xfs_map_blocks(inode, offset, size,
&imap, flags);
if (err)
@@ -1233,18 +1194,16 @@ xfs_page_state_convert(
*/
type = IO_NEW;
if (trylock_buffer(bh)) {
- ASSERT(buffer_mapped(bh));
if (imap_valid)
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)) {
+ ASSERT(buffer_mapped(bh));
imap_valid = 0;
}
@@ -1256,8 +1215,7 @@ 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;
@@ -1275,131 +1233,27 @@ 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);
- }
+ 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
@@ -1413,65 +1267,27 @@ 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,
- };
+ int delalloc, unwritten;
- trace_xfs_releasepage(inode, page, 0);
+ trace_xfs_releasepage(page->mapping->host, page, 0);
- if (!page_has_buffers(page))
- return 0;
-
- xfs_count_page_state(page, &delalloc, &unmapped, &unwritten);
- if (!delalloc && !unwritten)
- goto free_buffers;
+ xfs_count_page_state(page, &delalloc, &unwritten);
- 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);
}
@@ -1481,9 +1297,9 @@ __xfs_get_blocks(
sector_t iblock,
struct buffer_head *bh_result,
int create,
- int direct,
- bmapi_flags_t flags)
+ int direct)
{
+ int flags = create ? BMAPI_WRITE : BMAPI_READ;
struct xfs_bmbt_irec imap;
xfs_off_t offset;
ssize_t size;
@@ -1498,8 +1314,11 @@ __xfs_get_blocks(
if (!create && direct && offset >= i_size_read(inode))
return 0;
- error = xfs_iomap(XFS_I(inode), offset, size,
- create ? flags : BMAPI_READ, &imap, &nimap, &new);
+ if (direct && create)
+ flags |= BMAPI_DIRECT;
+
+ error = xfs_iomap(XFS_I(inode), offset, size, flags, &imap, &nimap,
+ &new);
if (error)
return -error;
if (nimap == 0)
@@ -1579,8 +1398,7 @@ xfs_get_blocks(
struct buffer_head *bh_result,
int create)
{
- return __xfs_get_blocks(inode, iblock,
- bh_result, create, 0, BMAPI_WRITE);
+ return __xfs_get_blocks(inode, iblock, bh_result, create, 0);
}
STATIC int
@@ -1590,61 +1408,59 @@ xfs_get_blocks_direct(
struct buffer_head *bh_result,
int create)
{
- return __xfs_get_blocks(inode, iblock,
- bh_result, create, 1, BMAPI_WRITE|BMAPI_DIRECT);
+ return __xfs_get_blocks(inode, iblock, bh_result, create, 1);
}
+/*
+ * Complete a direct I/O write request.
+ *
+ * If the private argument is non-NULL __xfs_get_blocks signals us that we
+ * need to issue a transaction to convert the range from unwritten to written
+ * extents. In case this is regular synchronous I/O we just call xfs_end_io
+ * to do this and we are done. But in case this was a successfull AIO
+ * request this handler is called from interrupt context, from which we
+ * can't start transactions. In that case offload the I/O completion to
+ * the workqueues we also use for buffered I/O completion.
+ */
STATIC void
-xfs_end_io_direct(
- struct kiocb *iocb,
- loff_t offset,
- ssize_t size,
- void *private)
+xfs_end_io_direct_write(
+ struct kiocb *iocb,
+ loff_t offset,
+ ssize_t size,
+ void *private,
+ int ret,
+ bool is_async)
{
- xfs_ioend_t *ioend = iocb->private;
+ struct xfs_ioend *ioend = iocb->private;
/*
- * Non-NULL private data means we need to issue a transaction to
- * convert a range from unwritten to written extents. This needs
- * to happen from process context but aio+dio I/O completion
- * happens from irq context so we need to defer it to a workqueue.
- * This is not necessary for synchronous direct I/O, but we do
- * it anyway to keep the code uniform and simpler.
- *
- * Well, if only it were that simple. Because synchronous direct I/O
- * requires extent conversion to occur *before* we return to userspace,
- * we have to wait for extent conversion to complete. Look at the
- * iocb that has been passed to us to determine if this is AIO or
- * not. If it is synchronous, tell xfs_finish_ioend() to kick the
- * workqueue and wait for it to complete.
- *
- * The core direct I/O code might be changed to always call the
- * completion handler in the future, in which case all this can
- * go away.
+ * blockdev_direct_IO can return an error even after the I/O
+ * completion handler was called. Thus we need to protect
+ * against double-freeing.
*/
+ iocb->private = NULL;
+
ioend->io_offset = offset;
ioend->io_size = size;
- if (ioend->io_type == IO_READ) {
- xfs_finish_ioend(ioend, 0);
- } else if (private && size > 0) {
- xfs_finish_ioend(ioend, is_sync_kiocb(iocb));
- } else {
+ if (private && size > 0)
+ ioend->io_type = IO_UNWRITTEN;
+
+ if (is_async) {
/*
- * A direct I/O write ioend starts it's life in unwritten
- * state in case they map an unwritten extent. This write
- * didn't map an unwritten extent so switch it's completion
- * handler.
+ * If we are converting an unwritten extent we need to delay
+ * the AIO completion until after the unwrittent extent
+ * conversion has completed, otherwise do it ASAP.
*/
- ioend->io_type = IO_NEW;
- xfs_finish_ioend(ioend, 0);
+ if (ioend->io_type == IO_UNWRITTEN) {
+ ioend->io_iocb = iocb;
+ ioend->io_result = ret;
+ } else {
+ aio_complete(iocb, ret, 0);
+ }
+ xfs_finish_ioend(ioend);
+ } else {
+ xfs_finish_ioend_sync(ioend);
}
-
- /*
- * blockdev_direct_IO can return an error even after the I/O
- * completion handler was called. Thus we need to protect
- * against double-freeing.
- */
- iocb->private = NULL;
}
STATIC ssize_t
@@ -1655,26 +1471,45 @@ xfs_vm_direct_IO(
loff_t offset,
unsigned long nr_segs)
{
- struct file *file = iocb->ki_filp;
- struct inode *inode = file->f_mapping->host;
- struct block_device *bdev;
- ssize_t ret;
+ struct inode *inode = iocb->ki_filp->f_mapping->host;
+ struct block_device *bdev = xfs_find_bdev_for_inode(inode);
+ ssize_t ret;
- bdev = xfs_find_bdev_for_inode(inode);
+ if (rw & WRITE) {
+ iocb->private = xfs_alloc_ioend(inode, IO_NEW);
- iocb->private = xfs_alloc_ioend(inode, rw == WRITE ?
- IO_UNWRITTEN : IO_READ);
-
- ret = blockdev_direct_IO_no_locking(rw, iocb, inode, bdev, iov,
+ ret = __blockdev_direct_IO(rw, iocb, inode, bdev, iov,
offset, nr_segs,
xfs_get_blocks_direct,
- xfs_end_io_direct);
+ xfs_end_io_direct_write, NULL, 0);
+ if (ret != -EIOCBQUEUED && iocb->private)
+ xfs_destroy_ioend(iocb->private);
+ } else {
+ ret = __blockdev_direct_IO(rw, iocb, inode, bdev, iov,
+ offset, nr_segs,
+ xfs_get_blocks_direct,
+ NULL, NULL, 0);
+ }
- if (unlikely(ret != -EIOCBQUEUED && iocb->private))
- xfs_destroy_ioend(iocb->private);
return ret;
}
+STATIC void
+xfs_vm_write_failed(
+ struct address_space *mapping,
+ loff_t to)
+{
+ struct inode *inode = mapping->host;
+
+ if (to > inode->i_size) {
+ struct iattr ia = {
+ .ia_valid = ATTR_SIZE | ATTR_FORCE,
+ .ia_size = inode->i_size,
+ };
+ xfs_setattr(XFS_I(inode), &ia, XFS_ATTR_NOLOCK);
+ }
+}
+
STATIC int
xfs_vm_write_begin(
struct file *file,
@@ -1685,9 +1520,31 @@ xfs_vm_write_begin(
struct page **pagep,
void **fsdata)
{
- *pagep = NULL;
- return block_write_begin(file, mapping, pos, len, flags, pagep, fsdata,
- xfs_get_blocks);
+ int ret;
+
+ ret = block_write_begin(mapping, pos, len, flags | AOP_FLAG_NOFS,
+ pagep, xfs_get_blocks);
+ if (unlikely(ret))
+ xfs_vm_write_failed(mapping, pos + len);
+ return ret;
+}
+
+STATIC int
+xfs_vm_write_end(
+ struct file *file,
+ struct address_space *mapping,
+ loff_t pos,
+ unsigned len,
+ unsigned copied,
+ struct page *page,
+ void *fsdata)
+{
+ int ret;
+
+ ret = generic_write_end(file, mapping, pos, len, copied, page, fsdata);
+ if (unlikely(ret < len))
+ xfs_vm_write_failed(mapping, pos + len);
+ return ret;
}
STATIC sector_t
@@ -1698,7 +1555,7 @@ xfs_vm_bmap(
struct inode *inode = (struct inode *)mapping->host;
struct xfs_inode *ip = XFS_I(inode);
- xfs_itrace_entry(XFS_I(inode));
+ trace_xfs_vm_bmap(XFS_I(inode));
xfs_ilock(ip, XFS_IOLOCK_SHARED);
xfs_flush_pages(ip, (xfs_off_t)0, -1, 0, FI_REMAPF);
xfs_iunlock(ip, XFS_IOLOCK_SHARED);
@@ -1732,7 +1589,7 @@ const struct address_space_operations xfs_address_space_operations = {
.releasepage = xfs_vm_releasepage,
.invalidatepage = xfs_vm_invalidatepage,
.write_begin = xfs_vm_write_begin,
- .write_end = generic_write_end,
+ .write_end = xfs_vm_write_end,
.bmap = xfs_vm_bmap,
.direct_IO = xfs_vm_direct_IO,
.migratepage = buffer_migrate_page,
Copyright © 1996 – 2023 Jason A. Donenfeld. All Rights Reverse Engineered.