#include "xfs_bmap_util.h"
#include "xfs_bmap_btree.h"
#include "xfs_reflink.h"
-#include <linux/gfp.h>
-#include <linux/mpage.h>
-#include <linux/pagevec.h>
#include <linux/writeback.h>
/*
struct xfs_ioend *ioend;
};
-void
-xfs_count_page_state(
- struct page *page,
- int *delalloc,
- int *unwritten)
-{
- struct buffer_head *bh, *head;
-
- *delalloc = *unwritten = 0;
-
- bh = head = page_buffers(page);
- do {
- if (buffer_unwritten(bh))
- (*unwritten) = 1;
- else if (buffer_delay(bh))
- (*delalloc) = 1;
- } while ((bh = bh->b_this_page) != head);
-}
-
struct block_device *
xfs_find_bdev_for_inode(
struct inode *inode)
struct bio_vec *bvec,
int error)
{
+ struct iomap_page *iop = to_iomap_page(bvec->bv_page);
+
if (error) {
SetPageError(bvec->bv_page);
mapping_set_error(inode->i_mapping, -EIO);
}
- end_page_writeback(bvec->bv_page);
-}
-/*
- * We're now finished for good with this page. Update the page state via the
- * associated buffer_heads, paying attention to the start and end offsets that
- * we need to process on the page.
- *
- * Note that we open code the action in end_buffer_async_write here so that we
- * only have to iterate over the buffers attached to the page once. This is not
- * only more efficient, but also ensures that we only calls end_page_writeback
- * at the end of the iteration, and thus avoids the pitfall of having the page
- * and buffers potentially freed after every call to end_buffer_async_write.
- */
-static void
-xfs_finish_buffer_writeback(
- struct inode *inode,
- struct bio_vec *bvec,
- int error)
-{
- struct buffer_head *head = page_buffers(bvec->bv_page), *bh = head;
- bool busy = false;
- unsigned int off = 0;
- unsigned long flags;
-
- ASSERT(bvec->bv_offset < PAGE_SIZE);
- ASSERT((bvec->bv_offset & (i_blocksize(inode) - 1)) == 0);
- ASSERT(bvec->bv_offset + bvec->bv_len <= PAGE_SIZE);
- ASSERT((bvec->bv_len & (i_blocksize(inode) - 1)) == 0);
-
- local_irq_save(flags);
- bit_spin_lock(BH_Uptodate_Lock, &head->b_state);
- do {
- if (off >= bvec->bv_offset &&
- off < bvec->bv_offset + bvec->bv_len) {
- ASSERT(buffer_async_write(bh));
- ASSERT(bh->b_end_io == NULL);
-
- if (error) {
- mark_buffer_write_io_error(bh);
- clear_buffer_uptodate(bh);
- SetPageError(bvec->bv_page);
- } else {
- set_buffer_uptodate(bh);
- }
- clear_buffer_async_write(bh);
- unlock_buffer(bh);
- } else if (buffer_async_write(bh)) {
- ASSERT(buffer_locked(bh));
- busy = true;
- }
- off += bh->b_size;
- } while ((bh = bh->b_this_page) != head);
- bit_spin_unlock(BH_Uptodate_Lock, &head->b_state);
- local_irq_restore(flags);
+ ASSERT(iop || i_blocksize(inode) == PAGE_SIZE);
+ ASSERT(!iop || atomic_read(&iop->write_count) > 0);
- if (!busy)
+ if (!iop || atomic_dec_and_test(&iop->write_count))
end_page_writeback(bvec->bv_page);
}
next = bio->bi_private;
/* walk each page on bio, ending page IO on them */
- bio_for_each_segment_all(bvec, bio, i) {
- if (page_has_buffers(bvec->bv_page))
- xfs_finish_buffer_writeback(inode, bvec, error);
- else
- xfs_finish_page_writeback(inode, bvec, error);
- }
+ bio_for_each_segment_all(bvec, bio, i)
+ xfs_finish_page_writeback(inode, bvec, error);
bio_put(bio);
}
struct inode *inode,
xfs_off_t offset,
struct page *page,
+ struct iomap_page *iop,
struct xfs_writepage_ctx *wpc,
struct writeback_control *wbc,
struct list_head *iolist)
bdev, sector);
}
- /*
- * If the block doesn't fit into the bio we need to allocate a new
- * one. This shouldn't happen more than once for a given block.
- */
- while (bio_add_page(wpc->ioend->io_bio, page, len, poff) != len)
- xfs_chain_bio(wpc->ioend, wbc, bdev, sector);
+ if (!__bio_try_merge_page(wpc->ioend->io_bio, page, len, poff)) {
+ if (iop)
+ atomic_inc(&iop->write_count);
+ if (bio_full(wpc->ioend->io_bio))
+ xfs_chain_bio(wpc->ioend, wbc, bdev, sector);
+ __bio_add_page(wpc->ioend->io_bio, page, len, poff);
+ }
wpc->ioend->io_size += len;
}
STATIC void
-xfs_map_buffer(
- struct inode *inode,
- struct buffer_head *bh,
- struct xfs_bmbt_irec *imap,
- xfs_off_t offset)
-{
- sector_t bn;
- struct xfs_mount *m = XFS_I(inode)->i_mount;
- xfs_off_t iomap_offset = XFS_FSB_TO_B(m, imap->br_startoff);
- xfs_daddr_t iomap_bn = xfs_fsb_to_db(XFS_I(inode), imap->br_startblock);
-
- ASSERT(imap->br_startblock != HOLESTARTBLOCK);
- ASSERT(imap->br_startblock != DELAYSTARTBLOCK);
-
- bn = (iomap_bn >> (inode->i_blkbits - BBSHIFT)) +
- ((offset - iomap_offset) >> inode->i_blkbits);
-
- ASSERT(bn || XFS_IS_REALTIME_INODE(XFS_I(inode)));
-
- bh->b_blocknr = bn;
- set_buffer_mapped(bh);
-}
-
-STATIC void
-xfs_map_at_offset(
- struct inode *inode,
- struct buffer_head *bh,
- struct xfs_bmbt_irec *imap,
- xfs_off_t offset)
-{
- ASSERT(imap->br_startblock != HOLESTARTBLOCK);
- ASSERT(imap->br_startblock != DELAYSTARTBLOCK);
-
- lock_buffer(bh);
- xfs_map_buffer(inode, bh, imap, offset);
- set_buffer_mapped(bh);
- clear_buffer_delay(bh);
- clear_buffer_unwritten(bh);
-
- /*
- * If this is a realtime file, data may be on a different device.
- * to that pointed to from the buffer_head b_bdev currently. We can't
- * trust that the bufferhead has a already been mapped correctly, so
- * set the bdev now.
- */
- bh->b_bdev = xfs_find_bdev_for_inode(inode);
- bh->b_end_io = NULL;
- set_buffer_async_write(bh);
- set_buffer_uptodate(bh);
- clear_buffer_dirty(bh);
-}
-
-STATIC void
xfs_vm_invalidatepage(
struct page *page,
unsigned int offset,
unsigned int length)
{
- trace_xfs_invalidatepage(page->mapping->host, page, offset,
- length);
-
- /*
- * If we are invalidating the entire page, clear the dirty state from it
- * so that we can check for attempts to release dirty cached pages in
- * xfs_vm_releasepage().
- */
- if (offset == 0 && length >= PAGE_SIZE)
- cancel_dirty_page(page);
- block_invalidatepage(page, offset, length);
+ trace_xfs_invalidatepage(page->mapping->host, page, offset, length);
+ iomap_invalidatepage(page, offset, length);
}
/*
- * If the page has delalloc buffers on it, we need to punch them out before we
- * invalidate the page. If we don't, we leave a stale delalloc mapping on the
- * inode that can trip a BUG() in xfs_get_blocks() later on if a direct IO read
- * is done on that same region - the delalloc extent is returned when none is
- * supposed to be there.
+ * If the page has delalloc blocks on it, we need to punch them out before we
+ * invalidate the page. If we don't, we leave a stale delalloc mapping on the
+ * inode that can trip up a later direct I/O read operation on the same region.
*
- * We prevent this by truncating away the delalloc regions on the page before
- * invalidating it. Because they are delalloc, we can do this without needing a
- * transaction. Indeed - if we get ENOSPC errors, we have to be able to do this
- * truncation without a transaction as there is no space left for block
- * reservation (typically why we see a ENOSPC in writeback).
+ * We prevent this by truncating away the delalloc regions on the page. Because
+ * they are delalloc, we can do this without needing a transaction. Indeed - if
+ * we get ENOSPC errors, we have to be able to do this truncation without a
+ * transaction as there is no space left for block reservation (typically why we
+ * see a ENOSPC in writeback).
*/
STATIC void
xfs_aops_discard_page(
* We implement an immediate ioend submission policy here to avoid needing to
* chain multiple ioends and hence nest mempool allocations which can violate
* forward progress guarantees we need to provide. The current ioend we are
- * adding buffers to is cached on the writepage context, and if the new buffer
+ * adding blocks to is cached on the writepage context, and if the new block
* does not append to the cached ioend it will create a new ioend and cache that
* instead.
*
uint64_t end_offset)
{
LIST_HEAD(submit_list);
+ struct iomap_page *iop = to_iomap_page(page);
+ unsigned len = i_blocksize(inode);
struct xfs_ioend *ioend, *next;
- struct buffer_head *bh = NULL;
- ssize_t len = i_blocksize(inode);
uint64_t file_offset; /* file offset of page */
- unsigned poffset; /* offset into page */
- int error = 0;
- int count = 0;
+ int error = 0, count = 0, i;
- if (page_has_buffers(page))
- bh = page_buffers(page);
+ ASSERT(iop || i_blocksize(inode) == PAGE_SIZE);
+ ASSERT(!iop || atomic_read(&iop->write_count) == 0);
/*
- * Walk the blocks on the page, and if we run off the end of the current
- * map or find the current map invalid, grab a new one. We only use
- * bufferheads here to check per-block state - they no longer control
- * the iteration through the page. This allows us to replace the
- * bufferhead with some other state tracking mechanism in future.
+ * Walk through the page to find areas to write back. If we run off the
+ * end of the current map or find the current map invalid, grab a new
+ * one.
*/
- for (poffset = 0, file_offset = page_offset(page);
- poffset < PAGE_SIZE;
- poffset += len, file_offset += len) {
- /* past the range we are writing, so nothing more to write. */
- if (file_offset >= end_offset)
- break;
-
- if (bh && !buffer_uptodate(bh)) {
- if (PageUptodate(page))
- ASSERT(buffer_mapped(bh));
- bh = bh->b_this_page;
+ for (i = 0, file_offset = page_offset(page);
+ i < (PAGE_SIZE >> inode->i_blkbits) && file_offset < end_offset;
+ i++, file_offset += len) {
+ if (iop && !test_bit(i, iop->uptodate))
continue;
- }
error = xfs_map_blocks(wpc, inode, file_offset);
if (error)
break;
-
- if (wpc->io_type == XFS_IO_HOLE) {
- if (bh)
- bh = bh->b_this_page;
+ if (wpc->io_type == XFS_IO_HOLE)
continue;
- }
-
- if (bh) {
- xfs_map_at_offset(inode, bh, &wpc->imap, file_offset);
- bh = bh->b_this_page;
- }
- xfs_add_to_ioend(inode, file_offset, page, wpc, wbc,
- &submit_list);
+ xfs_add_to_ioend(inode, file_offset, page, iop, wpc, wbc,
+ &submit_list);
count++;
}
ASSERT(!PageWriteback(page));
/*
- * On error, we have to fail the ioend here because we have locked
- * buffers in the ioend. If we don't do this, we'll deadlock
- * invalidating the page as that tries to lock the buffers on the page.
- * Also, because we may have set pages under writeback, we have to make
- * sure we run IO completion to mark the error state of the IO
- * appropriately, so we can't cancel the ioend directly here. That means
- * we have to mark this page as under writeback if we included any
- * buffers from it in the ioend chain so that completion treats it
- * correctly.
+ * On error, we have to fail the ioend here because we may have set
+ * pages under writeback, we have to make sure we run IO completion to
+ * mark the error state of the IO appropriately, so we can't cancel the
+ * ioend directly here. That means we have to mark this page as under
+ * writeback if we included any blocks from it in the ioend chain so
+ * that completion treats it correctly.
*
* If we didn't include the page in the ioend, the on error we can
* simply discard and unlock it as there are no other users of the page
- * or it's buffers right now. The caller will still need to trigger
- * submission of outstanding ioends on the writepage context so they are
- * treated correctly on error.
+ * now. The caller will still need to trigger submission of outstanding
+ * ioends on the writepage context so they are treated correctly on
+ * error.
*/
if (unlikely(error)) {
if (!count) {
}
/*
- * We can end up here with no error and nothing to write if we race with
- * a partial page truncate on a sub-page block sized filesystem.
+ * We can end up here with no error and nothing to write only if we race
+ * with a partial page truncate on a sub-page block sized filesystem.
*/
if (!count)
end_page_writeback(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 any other dirty buffer heads on the page we should flush them.
*/
STATIC int
xfs_do_writepage(
xfs_find_bdev_for_inode(mapping->host), wbc);
}
-/*
- * Called to move a page into cleanable state - and from there
- * to be released. The page should already be clean. We always
- * have buffer heads in this call.
- *
- * Returns 1 if the page is ok to release, 0 otherwise.
- */
STATIC int
xfs_vm_releasepage(
struct page *page,
gfp_t gfp_mask)
{
- int delalloc, unwritten;
-
trace_xfs_releasepage(page->mapping->host, page, 0, 0);
-
- /*
- * mm accommodates an old ext3 case where clean pages might not have had
- * the dirty bit cleared. Thus, it can send actual dirty pages to
- * ->releasepage() via shrink_active_list(). Conversely,
- * block_invalidatepage() can send pages that are still marked dirty but
- * otherwise have invalidated buffers.
- *
- * We want to release the latter to avoid unnecessary buildup of the
- * LRU, so xfs_vm_invalidatepage() clears the page dirty flag on pages
- * that are entirely invalidated and need to be released. Hence the
- * only time we should get dirty pages here is through
- * shrink_active_list() and so we can simply skip those now.
- *
- * warn if we've left any lingering delalloc/unwritten buffers on clean
- * or invalidated pages we are about to release.
- */
- if (PageDirty(page))
- return 0;
-
- xfs_count_page_state(page, &delalloc, &unwritten);
-
- if (WARN_ON_ONCE(delalloc))
- return 0;
- if (WARN_ON_ONCE(unwritten))
- return 0;
-
- return try_to_free_buffers(page);
-}
-
-/*
- * If this is O_DIRECT or the mpage code calling tell them how large the mapping
- * is, so that we can avoid repeated get_blocks calls.
- *
- * If the mapping spans EOF, then we have to break the mapping up as the mapping
- * for blocks beyond EOF must be marked new so that sub block regions can be
- * correctly zeroed. We can't do this for mappings within EOF unless the mapping
- * was just allocated or is unwritten, otherwise the callers would overwrite
- * existing data with zeros. Hence we have to split the mapping into a range up
- * to and including EOF, and a second mapping for beyond EOF.
- */
-static void
-xfs_map_trim_size(
- struct inode *inode,
- sector_t iblock,
- struct buffer_head *bh_result,
- struct xfs_bmbt_irec *imap,
- xfs_off_t offset,
- ssize_t size)
-{
- xfs_off_t mapping_size;
-
- mapping_size = imap->br_startoff + imap->br_blockcount - iblock;
- mapping_size <<= inode->i_blkbits;
-
- ASSERT(mapping_size > 0);
- if (mapping_size > size)
- mapping_size = size;
- if (offset < i_size_read(inode) &&
- (xfs_ufsize_t)offset + mapping_size >= i_size_read(inode)) {
- /* limit mapping to block that spans EOF */
- mapping_size = roundup_64(i_size_read(inode) - offset,
- i_blocksize(inode));
- }
- if (mapping_size > LONG_MAX)
- mapping_size = LONG_MAX;
-
- bh_result->b_size = mapping_size;
-}
-
-static int
-xfs_get_blocks(
- struct inode *inode,
- sector_t iblock,
- struct buffer_head *bh_result,
- int create)
-{
- struct xfs_inode *ip = XFS_I(inode);
- struct xfs_mount *mp = ip->i_mount;
- xfs_fileoff_t offset_fsb, end_fsb;
- int error = 0;
- int lockmode = 0;
- struct xfs_bmbt_irec imap;
- int nimaps = 1;
- xfs_off_t offset;
- ssize_t size;
-
- BUG_ON(create);
-
- if (XFS_FORCED_SHUTDOWN(mp))
- return -EIO;
-
- offset = (xfs_off_t)iblock << inode->i_blkbits;
- ASSERT(bh_result->b_size >= i_blocksize(inode));
- size = bh_result->b_size;
-
- if (offset >= i_size_read(inode))
- return 0;
-
- /*
- * Direct I/O is usually done on preallocated files, so try getting
- * a block mapping without an exclusive lock first.
- */
- lockmode = xfs_ilock_data_map_shared(ip);
-
- ASSERT(offset <= mp->m_super->s_maxbytes);
- if (offset > mp->m_super->s_maxbytes - size)
- size = mp->m_super->s_maxbytes - offset;
- end_fsb = XFS_B_TO_FSB(mp, (xfs_ufsize_t)offset + size);
- offset_fsb = XFS_B_TO_FSBT(mp, offset);
-
- error = xfs_bmapi_read(ip, offset_fsb, end_fsb - offset_fsb, &imap,
- &nimaps, 0);
- if (error)
- goto out_unlock;
- if (!nimaps) {
- trace_xfs_get_blocks_notfound(ip, offset, size);
- goto out_unlock;
- }
-
- trace_xfs_get_blocks_found(ip, offset, size,
- imap.br_state == XFS_EXT_UNWRITTEN ?
- XFS_IO_UNWRITTEN : XFS_IO_OVERWRITE, &imap);
- xfs_iunlock(ip, lockmode);
-
- /* trim mapping down to size requested */
- xfs_map_trim_size(inode, iblock, bh_result, &imap, offset, size);
-
- /*
- * For unwritten extents do not report a disk address in the buffered
- * read case (treat as if we're reading into a hole).
- */
- if (xfs_bmap_is_real_extent(&imap))
- xfs_map_buffer(inode, bh_result, &imap, offset);
-
- /*
- * If this is a realtime file, data may be on a different device.
- * to that pointed to from the buffer_head b_bdev currently.
- */
- bh_result->b_bdev = xfs_find_bdev_for_inode(inode);
- return 0;
-
-out_unlock:
- xfs_iunlock(ip, lockmode);
- return error;
+ return iomap_releasepage(page, gfp_mask);
}
STATIC sector_t
struct page *page)
{
trace_xfs_vm_readpage(page->mapping->host, 1);
- if (i_blocksize(page->mapping->host) == PAGE_SIZE)
- return iomap_readpage(page, &xfs_iomap_ops);
- return mpage_readpage(page, xfs_get_blocks);
+ return iomap_readpage(page, &xfs_iomap_ops);
}
STATIC int
unsigned nr_pages)
{
trace_xfs_vm_readpages(mapping->host, nr_pages);
- if (i_blocksize(mapping->host) == PAGE_SIZE)
- return iomap_readpages(mapping, pages, nr_pages, &xfs_iomap_ops);
- return mpage_readpages(mapping, pages, nr_pages, xfs_get_blocks);
-}
-
-/*
- * This is basically a copy of __set_page_dirty_buffers() with one
- * small tweak: buffers beyond EOF do not get marked dirty. If we mark them
- * dirty, we'll never be able to clean them because we don't write buffers
- * beyond EOF, and that means we can't invalidate pages that span EOF
- * that have been marked dirty. Further, the dirty state can leak into
- * the file interior if the file is extended, resulting in all sorts of
- * bad things happening as the state does not match the underlying data.
- *
- * XXX: this really indicates that bufferheads in XFS need to die. Warts like
- * this only exist because of bufferheads and how the generic code manages them.
- */
-STATIC int
-xfs_vm_set_page_dirty(
- struct page *page)
-{
- struct address_space *mapping = page->mapping;
- struct inode *inode = mapping->host;
- loff_t end_offset;
- loff_t offset;
- int newly_dirty;
-
- if (unlikely(!mapping))
- return !TestSetPageDirty(page);
-
- end_offset = i_size_read(inode);
- offset = page_offset(page);
-
- spin_lock(&mapping->private_lock);
- if (page_has_buffers(page)) {
- struct buffer_head *head = page_buffers(page);
- struct buffer_head *bh = head;
-
- do {
- if (offset < end_offset)
- set_buffer_dirty(bh);
- bh = bh->b_this_page;
- offset += i_blocksize(inode);
- } while (bh != head);
- }
- /*
- * Lock out page->mem_cgroup migration to keep PageDirty
- * synchronized with per-memcg dirty page counters.
- */
- lock_page_memcg(page);
- newly_dirty = !TestSetPageDirty(page);
- spin_unlock(&mapping->private_lock);
-
- if (newly_dirty)
- __set_page_dirty(page, mapping, 1);
- unlock_page_memcg(page);
- if (newly_dirty)
- __mark_inode_dirty(mapping->host, I_DIRTY_PAGES);
- return newly_dirty;
+ return iomap_readpages(mapping, pages, nr_pages, &xfs_iomap_ops);
}
static int
.readpages = xfs_vm_readpages,
.writepage = xfs_vm_writepage,
.writepages = xfs_vm_writepages,
- .set_page_dirty = xfs_vm_set_page_dirty,
+ .set_page_dirty = iomap_set_page_dirty,
.releasepage = xfs_vm_releasepage,
.invalidatepage = xfs_vm_invalidatepage,
.bmap = xfs_vm_bmap,
.direct_IO = noop_direct_IO,
- .migratepage = buffer_migrate_page,
- .is_partially_uptodate = block_is_partially_uptodate,
+ .migratepage = iomap_migrate_page,
+ .is_partially_uptodate = iomap_is_partially_uptodate,
.error_remove_page = generic_error_remove_page,
.swap_activate = xfs_iomap_swapfile_activate,
};
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