#include "xfs_rw.h"
#include "xfs_iomap.h"
#include <linux/mpage.h>
+#include <linux/pagevec.h>
#include <linux/writeback.h>
STATIC void xfs_count_page_state(struct page *, int *, int *, int *);
int mask)
{
xfs_inode_t *ip;
- bhv_desc_t *bdp;
vnode_t *vp = LINVFS_GET_VP(inode);
loff_t isize = i_size_read(inode);
loff_t offset = page_offset(page);
if (page_has_buffers(page))
xfs_count_page_state(page, &delalloc, &unmapped, &unwritten);
- bdp = vn_bhv_lookup(VN_BHV_HEAD(vp), &xfs_vnodeops);
- ip = XFS_BHVTOI(bdp);
+ ip = xfs_vtoi(vp);
if (!ip->i_rwtrace)
return;
return -error;
}
-/*
- * Finds the corresponding mapping in block @map array of the
- * given @offset within a @page.
- */
-STATIC xfs_iomap_t *
-xfs_offset_to_map(
- struct page *page,
+STATIC inline int
+xfs_iomap_valid(
xfs_iomap_t *iomapp,
- unsigned long offset)
+ loff_t offset)
{
- xfs_off_t full_offset; /* offset from start of file */
-
- ASSERT(offset < PAGE_CACHE_SIZE);
-
- full_offset = page->index; /* NB: using 64bit number */
- full_offset <<= PAGE_CACHE_SHIFT; /* offset from file start */
- full_offset += offset; /* offset from page start */
-
- if (full_offset < iomapp->iomap_offset)
- return NULL;
- if (iomapp->iomap_offset + (iomapp->iomap_bsize -1) >= full_offset)
- return iomapp;
- return NULL;
+ return offset >= iomapp->iomap_offset &&
+ offset < iomapp->iomap_offset + iomapp->iomap_bsize;
}
/*
}
/*
- * Submit all of the bios for all of the ioends we have saved up,
- * covering the initial writepage page and also any probed pages.
+ * Submit all of the bios for all of the ioends we have saved up, covering the
+ * initial writepage page and also any probed pages.
+ *
+ * Because we may have multiple ioends spanning a page, we need to start
+ * writeback on all the buffers before we submit them for I/O. If we mark the
+ * buffers as we got, then we can end up with a page that only has buffers
+ * marked async write and I/O complete on can occur before we mark the other
+ * buffers async write.
+ *
+ * The end result of this is that we trip a bug in end_page_writeback() because
+ * we call it twice for the one page as the code in end_buffer_async_write()
+ * assumes that all buffers on the page are started at the same time.
+ *
+ * The fix is two passes across the ioend list - one to start writeback on the
+ * bufferheads, and then the second one submit them for I/O.
*/
STATIC void
xfs_submit_ioend(
xfs_ioend_t *ioend)
{
+ xfs_ioend_t *head = ioend;
xfs_ioend_t *next;
struct buffer_head *bh;
struct bio *bio;
sector_t lastblock = 0;
+ /* Pass 1 - start writeback */
+ do {
+ next = ioend->io_list;
+ for (bh = ioend->io_buffer_head; bh; bh = bh->b_private) {
+ xfs_start_buffer_writeback(bh);
+ }
+ } while ((ioend = next) != NULL);
+
+ /* Pass 2 - submit I/O */
+ ioend = head;
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:
xfs_add_to_ioend(
struct inode *inode,
struct buffer_head *bh,
- unsigned int p_offset,
+ xfs_off_t offset,
unsigned int type,
xfs_ioend_t **result,
int need_ioend)
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;
STATIC void
xfs_map_at_offset(
- struct page *page,
struct buffer_head *bh,
- unsigned long offset,
+ loff_t offset,
int block_bits,
- xfs_iomap_t *iomapp,
- xfs_ioend_t *ioend)
+ xfs_iomap_t *iomapp)
{
xfs_daddr_t bn;
- xfs_off_t delta;
int sector_shift;
ASSERT(!(iomapp->iomap_flags & IOMAP_HOLE));
ASSERT(!(iomapp->iomap_flags & IOMAP_DELAY));
ASSERT(iomapp->iomap_bn != IOMAP_DADDR_NULL);
- delta = page->index;
- delta <<= PAGE_CACHE_SHIFT;
- delta += offset;
- delta -= iomapp->iomap_offset;
- delta >>= block_bits;
-
sector_shift = block_bits - BBSHIFT;
- bn = iomapp->iomap_bn >> sector_shift;
- bn += delta;
- BUG_ON(!bn && !(iomapp->iomap_flags & IOMAP_REALTIME));
+ bn = (iomapp->iomap_bn >> sector_shift) +
+ ((offset - iomapp->iomap_offset) >> block_bits);
+
+ ASSERT(bn || (iomapp->iomap_flags & IOMAP_REALTIME));
ASSERT((bn << sector_shift) >= iomapp->iomap_bn);
lock_buffer(bh);
}
/*
- * Look for a page at index which is unlocked and not mapped
- * yet - clustering for mmap write case.
+ * Look for a page at index that is suitable for clustering.
*/
STATIC unsigned int
-xfs_probe_unmapped_page(
- struct address_space *mapping,
- pgoff_t index,
- unsigned int pg_offset)
+xfs_probe_page(
+ struct page *page,
+ unsigned int pg_offset,
+ int mapped)
{
- struct page *page;
int ret = 0;
- page = find_trylock_page(mapping, index);
- if (!page)
- return 0;
if (PageWriteback(page))
- goto out;
+ return 0;
if (page->mapping && PageDirty(page)) {
if (page_has_buffers(page)) {
bh = head = page_buffers(page);
do {
- if (buffer_mapped(bh) || !buffer_uptodate(bh))
+ 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 = PAGE_CACHE_SIZE;
+ ret = mapped ? 0 : PAGE_CACHE_SIZE;
}
-out:
- unlock_page(page);
return ret;
}
STATIC size_t
-xfs_probe_unmapped_cluster(
+xfs_probe_cluster(
struct inode *inode,
struct page *startpage,
struct buffer_head *bh,
- struct buffer_head *head)
+ struct buffer_head *head,
+ int mapped)
{
- size_t len, total = 0;
+ struct pagevec pvec;
pgoff_t tindex, tlast, tloff;
- unsigned int pg_offset;
- struct address_space *mapping = inode->i_mapping;
+ size_t total = 0;
+ int done = 0, i;
/* First sum forwards in this page */
do {
- if (buffer_mapped(bh))
- break;
+ if (!buffer_uptodate(bh) || (mapped != buffer_mapped(bh)))
+ return total;
total += bh->b_size;
} while ((bh = bh->b_this_page) != head);
- /* If we reached the end of the page, sum forwards in
- * following pages.
- */
- if (bh == head) {
- tlast = i_size_read(inode) >> PAGE_CACHE_SHIFT;
- /* Prune this back to avoid pathological behavior */
- tloff = min(tlast, startpage->index + 64);
- for (tindex = startpage->index + 1; tindex < tloff; tindex++) {
- len = xfs_probe_unmapped_page(mapping, tindex,
- PAGE_CACHE_SIZE);
- if (!len)
- return total;
+ /* if we reached the end of the page, sum forwards in following pages */
+ tlast = i_size_read(inode) >> PAGE_CACHE_SHIFT;
+ tindex = startpage->index + 1;
+
+ /* Prune this back to avoid pathological behavior */
+ tloff = min(tlast, startpage->index + 64);
+
+ pagevec_init(&pvec, 0);
+ while (!done && tindex <= tloff) {
+ unsigned len = min_t(pgoff_t, PAGEVEC_SIZE, tlast - tindex + 1);
+
+ if (!pagevec_lookup(&pvec, inode->i_mapping, tindex, len))
+ break;
+
+ for (i = 0; i < pagevec_count(&pvec); i++) {
+ struct page *page = pvec.pages[i];
+ size_t pg_offset, len = 0;
+
+ if (tindex == tlast) {
+ pg_offset =
+ i_size_read(inode) & (PAGE_CACHE_SIZE - 1);
+ if (!pg_offset) {
+ done = 1;
+ break;
+ }
+ } else
+ pg_offset = PAGE_CACHE_SIZE;
+
+ if (page->index == tindex && !TestSetPageLocked(page)) {
+ len = xfs_probe_page(page, pg_offset, mapped);
+ unlock_page(page);
+ }
+
+ if (!len) {
+ done = 1;
+ break;
+ }
+
total += len;
+ tindex++;
}
- if (tindex == tlast &&
- (pg_offset = i_size_read(inode) & (PAGE_CACHE_SIZE - 1))) {
- total += xfs_probe_unmapped_page(mapping,
- tindex, pg_offset);
- }
+
+ pagevec_release(&pvec);
+ cond_resched();
}
+
return total;
}
/*
- * 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.
+ * Test if a given page is suitable for writing as part of an unwritten
+ * or delayed allocate extent.
*/
-STATIC struct page *
-xfs_probe_delayed_page(
- struct inode *inode,
- pgoff_t index,
+STATIC int
+xfs_is_delayed_page(
+ struct page *page,
unsigned int type)
{
- struct page *page;
-
- page = find_trylock_page(inode->i_mapping, index);
- if (!page)
- return NULL;
if (PageWriteback(page))
- goto out;
+ return 0;
if (page->mapping && page_has_buffers(page)) {
struct buffer_head *bh, *head;
acceptable = (type == IOMAP_UNWRITTEN);
else if (buffer_delay(bh))
acceptable = (type == IOMAP_DELAY);
+ else if (buffer_mapped(bh))
+ acceptable = (type == 0);
else
break;
} while ((bh = bh->b_this_page) != head);
if (acceptable)
- return page;
+ return 1;
}
-out:
- unlock_page(page);
- return NULL;
+ return 0;
}
/*
xfs_convert_page(
struct inode *inode,
struct page *page,
- xfs_iomap_t *iomapp,
+ loff_t tindex,
+ xfs_iomap_t *mp,
xfs_ioend_t **ioendp,
struct writeback_control *wbc,
- void *private,
int startio,
int all_bh)
{
struct buffer_head *bh, *head;
- xfs_iomap_t *mp = iomapp, *tmp;
- unsigned long p_offset, end_offset;
+ xfs_off_t end_offset;
+ unsigned long p_offset;
unsigned int type;
int bbits = inode->i_blkbits;
int len, page_dirty;
int count = 0, done = 0, uptodate = 1;
+ xfs_off_t offset = page_offset(page);
- end_offset = (i_size_read(inode) & (PAGE_CACHE_SIZE - 1));
+ if (page->index != tindex)
+ goto fail;
+ if (TestSetPageLocked(page))
+ goto fail;
+ if (PageWriteback(page))
+ goto fail_unlock_page;
+ if (page->mapping != inode->i_mapping)
+ goto fail_unlock_page;
+ if (!xfs_is_delayed_page(page, (*ioendp)->io_type))
+ goto fail_unlock_page;
/*
* 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,
+ i_size_read(inode));
+
len = 1 << inode->i_blkbits;
- end_offset = max(end_offset, PAGE_CACHE_SIZE);
- end_offset = roundup(end_offset, len);
- page_dirty = end_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;
- p_offset = 0;
bh = head = page_buffers(page);
do {
- if (p_offset >= end_offset)
+ if (offset >= end_offset)
break;
if (!buffer_uptodate(bh))
uptodate = 0;
continue;
}
- 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)) {
+ if (buffer_unwritten(bh) || buffer_delay(bh)) {
+ if (buffer_unwritten(bh))
+ type = IOMAP_UNWRITTEN;
+ else
+ type = IOMAP_DELAY;
+
+ if (!xfs_iomap_valid(mp, offset)) {
done = 1;
- } else if (startio) {
+ continue;
+ }
+
+ ASSERT(!(mp->iomap_flags & IOMAP_HOLE));
+ ASSERT(!(mp->iomap_flags & IOMAP_DELAY));
+
+ xfs_map_at_offset(bh, offset, bbits, mp);
+ if (startio) {
+ xfs_add_to_ioend(inode, bh, offset,
+ type, ioendp, done);
+ } else {
+ set_buffer_dirty(bh);
+ unlock_buffer(bh);
+ mark_buffer_dirty(bh);
+ }
+ page_dirty--;
+ count++;
+ } else {
+ type = 0;
+ if (buffer_mapped(bh) && all_bh && startio) {
lock_buffer(bh);
- xfs_add_to_ioend(inode, bh, p_offset,
+ xfs_add_to_ioend(inode, bh, offset,
type, ioendp, done);
count++;
page_dirty--;
+ } else {
+ done = 1;
}
- continue;
- }
- 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));
-
- xfs_map_at_offset(page, bh, p_offset, bbits, tmp, *ioendp);
- if (startio) {
- 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 (p_offset += len, (bh = bh->b_this_page) != head);
+ } while (offset += len, (bh = bh->b_this_page) != head);
if (uptodate && bh == head)
SetPageUptodate(page);
if (startio) {
- if (count)
+ if (count) {
+ struct backing_dev_info *bdi;
+
+ bdi = inode->i_mapping->backing_dev_info;
wbc->nr_to_write--;
+ if (bdi_write_congested(bdi)) {
+ wbc->encountered_congestion = 1;
+ done = 1;
+ } else if (wbc->nr_to_write <= 0) {
+ done = 1;
+ }
+ }
xfs_start_page_writeback(page, wbc, !page_dirty, count);
}
return done;
+ fail_unlock_page:
+ unlock_page(page);
+ fail:
+ return 1;
}
/*
int all_bh,
pgoff_t tlast)
{
- struct page *page;
- unsigned int type = (*ioendp)->io_type;
- int done;
+ struct pagevec pvec;
+ int done = 0, i;
- for (done = 0; tindex <= tlast && !done; tindex++) {
- page = xfs_probe_delayed_page(inode, tindex, type);
- if (!page)
+ pagevec_init(&pvec, 0);
+ while (!done && tindex <= tlast) {
+ unsigned len = min_t(pgoff_t, PAGEVEC_SIZE, tlast - tindex + 1);
+
+ if (!pagevec_lookup(&pvec, inode->i_mapping, tindex, len))
break;
- done = xfs_convert_page(inode, page, iomapp, ioendp,
- wbc, NULL, startio, all_bh);
+
+ for (i = 0; i < pagevec_count(&pvec); i++) {
+ done = xfs_convert_page(inode, pvec.pages[i], tindex++,
+ iomapp, ioendp, wbc, startio, all_bh);
+ if (done)
+ break;
+ }
+
+ pagevec_release(&pvec);
+ cond_resched();
}
}
int unmapped) /* also implies page uptodate */
{
struct buffer_head *bh, *head;
- xfs_iomap_t *iomp, iomap;
+ xfs_iomap_t 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 flags, len, err, done = 1;
- int uptodate = 1;
+ ssize_t size, len;
+ int flags, err, iomap_valid = 0, uptodate = 1;
int page_dirty, count = 0, trylock_flag = 0;
+ int all_bh = unmapped;
/* wait for other IO threads? */
- if (startio && wbc->sync_mode != WB_SYNC_NONE)
+ if (startio && (wbc->sync_mode == WB_SYNC_NONE && wbc->nonblocking))
trylock_flag |= BMAPI_TRYLOCK;
/* Is this page beyond the end of the file? */
p_offset = p_offset ? roundup(p_offset, len) : PAGE_CACHE_SIZE;
page_dirty = p_offset / len;
- iomp = NULL;
bh = head = page_buffers(page);
offset = page_offset(page);
+ flags = -1;
+ type = 0;
- /* TODO: fix up "done" variable and iomap pointer (boolean) */
/* TODO: cleanup count and page_dirty */
do {
if (!buffer_uptodate(bh))
uptodate = 0;
if (!(PageUptodate(page) || buffer_uptodate(bh)) && !startio) {
- done = 1;
+ /*
+ * the iomap is actually still valid, but the ioend
+ * isn't. shouldn't happen too often.
+ */
+ iomap_valid = 0;
continue;
}
- if (iomp) {
- iomp = xfs_offset_to_map(page, &iomap, p_offset);
- done = (iomp == NULL);
- }
+ if (iomap_valid)
+ iomap_valid = xfs_iomap_valid(&iomap, offset);
/*
* First case, map an unwritten extent and prepare for
*
* Second case, allocate space for a delalloc buffer.
* We can return EAGAIN here in the release page case.
- */
- if (buffer_unwritten(bh) || buffer_delay(bh)) {
+ *
+ * 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))) {
+ /*
+ * Make sure we don't use a read-only iomap
+ */
+ if (flags == BMAPI_READ)
+ iomap_valid = 0;
+
if (buffer_unwritten(bh)) {
type = IOMAP_UNWRITTEN;
flags = BMAPI_WRITE|BMAPI_IGNSTATE;
- } else {
+ } else if (buffer_delay(bh)) {
type = IOMAP_DELAY;
flags = BMAPI_ALLOCATE;
if (!startio)
flags |= trylock_flag;
+ } else {
+ type = IOMAP_NEW;
+ flags = BMAPI_WRITE|BMAPI_MMAP;
}
- if (!iomp) {
- done = 1;
- err = xfs_map_blocks(inode, offset, len, &iomap,
- flags);
+ if (!iomap_valid) {
+ if (type == IOMAP_NEW) {
+ size = xfs_probe_cluster(inode,
+ page, bh, head, 0);
+ } else {
+ size = len;
+ }
+
+ err = xfs_map_blocks(inode, offset, size,
+ &iomap, flags);
if (err)
goto error;
- iomp = xfs_offset_to_map(page, &iomap,
- p_offset);
- done = (iomp == NULL);
+ iomap_valid = xfs_iomap_valid(&iomap, offset);
}
- if (iomp) {
- xfs_map_at_offset(page, bh, p_offset,
- inode->i_blkbits, iomp, ioend);
+ if (iomap_valid) {
+ xfs_map_at_offset(bh, offset,
+ inode->i_blkbits, &iomap);
if (startio) {
- xfs_add_to_ioend(inode, bh, p_offset,
- type, &ioend, done);
+ xfs_add_to_ioend(inode, bh, offset,
+ type, &ioend,
+ !iomap_valid);
} else {
set_buffer_dirty(bh);
unlock_buffer(bh);
}
page_dirty--;
count++;
- } else {
- done = 1;
}
- } else if ((buffer_uptodate(bh) || PageUptodate(page)) &&
- (unmapped || startio)) {
+ } else if (buffer_uptodate(bh) && startio) {
+ /*
+ * we got here because the buffer is already mapped.
+ * That means it must already have extents allocated
+ * underneath it. Map the extent by reading it.
+ */
+ if (!iomap_valid || type != 0) {
+ flags = BMAPI_READ;
+ size = xfs_probe_cluster(inode, page, bh,
+ head, 1);
+ err = xfs_map_blocks(inode, offset, size,
+ &iomap, flags);
+ if (err)
+ goto error;
+ iomap_valid = xfs_iomap_valid(&iomap, offset);
+ }
type = 0;
- if (!buffer_mapped(bh)) {
-
- /*
- * Getting here implies an unmapped buffer
- * was found, and we are in a path where we
- * 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,
- size, &iomap,
- BMAPI_WRITE|BMAPI_MMAP);
- 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,
- ioend);
- if (startio) {
- 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)) {
- ASSERT(buffer_mapped(bh));
- xfs_add_to_ioend(inode,
- bh, p_offset, type,
- &ioend, done);
- page_dirty--;
- count++;
- } else {
- done = 1;
- }
+ if (!test_and_set_bit(BH_Lock, &bh->b_state)) {
+ ASSERT(buffer_mapped(bh));
+ if (iomap_valid)
+ all_bh = 1;
+ xfs_add_to_ioend(inode, bh, offset, type,
+ &ioend, !iomap_valid);
+ page_dirty--;
+ count++;
} else {
- done = 1;
+ iomap_valid = 0;
}
+ } else if ((buffer_uptodate(bh) || PageUptodate(page)) &&
+ (unmapped || startio)) {
+ iomap_valid = 0;
}
if (!iohead)
if (startio)
xfs_start_page_writeback(page, wbc, 1, count);
- if (ioend && iomp && !done) {
- offset = (iomp->iomap_offset + iomp->iomap_bsize - 1) >>
+ if (ioend && iomap_valid) {
+ offset = (iomap.iomap_offset + iomap.iomap_bsize - 1) >>
PAGE_CACHE_SHIFT;
tlast = min_t(pgoff_t, offset, last_index);
- xfs_cluster_write(inode, page->index + 1, iomp, &ioend,
- wbc, startio, unmapped, tlast);
+ xfs_cluster_write(inode, page->index + 1, &iomap, &ioend,
+ wbc, startio, all_bh, tlast);
}
if (iohead)
.commit_write = generic_commit_write,
.bmap = linvfs_bmap,
.direct_IO = linvfs_direct_IO,
+ .migratepage = buffer_migrate_page,
};
projects / linux-2.6-omap-h63xx.git / blobdiff