From f6d6d4fcd180f8e47bf6b13fc6cce1e6c156d0ea Mon Sep 17 00:00:00 2001 From: Christoph Hellwig Date: Wed, 11 Jan 2006 15:40:13 +1100 Subject: [PATCH] [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 Signed-off-by: Nathan Scott --- fs/xfs/linux-2.6/xfs_aops.c | 776 +++++++++++++++++++---------------- fs/xfs/linux-2.6/xfs_aops.h | 10 + fs/xfs/linux-2.6/xfs_iops.h | 5 - fs/xfs/linux-2.6/xfs_linux.h | 4 - 4 files changed, 431 insertions(+), 364 deletions(-) diff --git a/fs/xfs/linux-2.6/xfs_aops.c b/fs/xfs/linux-2.6/xfs_aops.c index 3f6b9e29850c..e99d04d3fe82 100644 --- a/fs/xfs/linux-2.6/xfs_aops.c +++ b/fs/xfs/linux-2.6/xfs_aops.c @@ -43,8 +43,6 @@ #include 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 @@ xfs_page_trace( 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 @@ xfs_finish_ioend( 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 @@ xfs_end_bio_unwritten( 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 @@ xfs_end_bio_unwritten( */ STATIC xfs_ioend_t * xfs_alloc_ioend( - struct inode *inode) + struct inode *inode, + unsigned int type) { xfs_ioend_t *ioend; @@ -162,45 +191,25 @@ xfs_alloc_ioend( */ 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_offset_to_map( 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 @@ xfs_offset_to_map( 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 @@ xfs_map_at_offset( 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 @@ xfs_probe_unmapped_page( 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 @@ xfs_probe_unmapped_cluster( } /* - * 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 @@ xfs_probe_delalloc_page( 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 @@ xfs_probe_delalloc_page( 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 @@ xfs_convert_page( 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 @@ xfs_cluster_write( 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 @@ xfs_page_state_convert( 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 @@ xfs_page_state_convert( } } - 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 @@ xfs_page_state_convert( * 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 @@ xfs_page_state_convert( } 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 @@ xfs_page_state_convert( * us to try again. */ if (err != -EAGAIN) { - if (!unmapped) { + if (!unmapped) block_invalidatepage(page, 0); - } ClearPageUptodate(page); } return err; @@ -1094,7 +1160,7 @@ linvfs_direct_IO( 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, diff --git a/fs/xfs/linux-2.6/xfs_aops.h b/fs/xfs/linux-2.6/xfs_aops.h index 4720758a9ade..55339dd5a30d 100644 --- a/fs/xfs/linux-2.6/xfs_aops.h +++ b/fs/xfs/linux-2.6/xfs_aops.h @@ -23,14 +23,24 @@ extern mempool_t *xfs_ioend_pool; typedef void (*xfs_ioend_func_t)(void *); +/* + * xfs_ioend struct manages large extent writes for XFS. + * It can manage several multi-page bio's at once. + */ typedef struct xfs_ioend { + struct xfs_ioend *io_list; /* next ioend in chain */ + unsigned int io_type; /* delalloc / unwritten */ unsigned int io_uptodate; /* I/O status register */ atomic_t io_remaining; /* hold count */ struct vnode *io_vnode; /* file being written to */ struct buffer_head *io_buffer_head;/* buffer linked list head */ + struct buffer_head *io_buffer_tail;/* buffer linked list tail */ size_t io_size; /* size of the extent */ xfs_off_t io_offset; /* offset in the file */ struct work_struct io_work; /* xfsdatad work queue */ } xfs_ioend_t; +extern struct address_space_operations linvfs_aops; +extern int linvfs_get_block(struct inode *, sector_t, struct buffer_head *, int); + #endif /* __XFS_IOPS_H__ */ diff --git a/fs/xfs/linux-2.6/xfs_iops.h b/fs/xfs/linux-2.6/xfs_iops.h index ee784b63acbf..6899a6b4a50a 100644 --- a/fs/xfs/linux-2.6/xfs_iops.h +++ b/fs/xfs/linux-2.6/xfs_iops.h @@ -26,11 +26,6 @@ extern struct file_operations linvfs_file_operations; extern struct file_operations linvfs_invis_file_operations; extern struct file_operations linvfs_dir_operations; -extern struct address_space_operations linvfs_aops; - -extern int linvfs_get_block(struct inode *, sector_t, struct buffer_head *, int); -extern void linvfs_unwritten_done(struct buffer_head *, int); - extern int xfs_ioctl(struct bhv_desc *, struct inode *, struct file *, int, unsigned int, void __user *); diff --git a/fs/xfs/linux-2.6/xfs_linux.h b/fs/xfs/linux-2.6/xfs_linux.h index 95efe948a095..67389b745526 100644 --- a/fs/xfs/linux-2.6/xfs_linux.h +++ b/fs/xfs/linux-2.6/xfs_linux.h @@ -110,10 +110,6 @@ * delalloc and these ondisk-uninitialised buffers. */ BUFFER_FNS(PrivateStart, unwritten); -static inline void set_buffer_unwritten_io(struct buffer_head *bh) -{ - bh->b_end_io = linvfs_unwritten_done; -} #define restricted_chown xfs_params.restrict_chown.val #define irix_sgid_inherit xfs_params.sgid_inherit.val -- GitLab