From 1defeac9d4fffa3eabc4fba887e8ff5b1da7f361 Mon Sep 17 00:00:00 2001 From: Christoph Hellwig Date: Wed, 11 Jan 2006 20:48:33 +1100 Subject: [PATCH] [XFS] clean up the xfs_offset_to_map interface Currently we pass a struct page and a relative offset into that page around, and returns the current xfs_iomap_t if the block at the specified offset fits into it, or a NULL pointer otherwise. This patch passed the full 64bit offset into the inode that all callers have anyway, and changes the return value to a simple boolean. Also the function gets a more descriptive name: xfs_iomap_valid. SGI-PV: 947118 SGI-Modid: xfs-linux-melb:xfs-kern:203825a Signed-off-by: Christoph Hellwig Signed-off-by: Nathan Scott --- fs/xfs/linux-2.6/xfs_aops.c | 136 +++++++++++++++++--------------------------- 1 file changed, 53 insertions(+), 83 deletions(-) diff --git a/fs/xfs/linux-2.6/xfs_aops.c b/fs/xfs/linux-2.6/xfs_aops.c index e998009..b306e25 100644 --- a/fs/xfs/linux-2.6/xfs_aops.c +++ b/fs/xfs/linux-2.6/xfs_aops.c @@ -228,29 +228,13 @@ xfs_map_blocks( 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; } /* @@ -461,31 +445,23 @@ xfs_add_to_ioend( 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); @@ -569,8 +545,10 @@ xfs_probe_unmapped_cluster( if (tindex == tlast) { pg_offset = i_size_read(inode) & (PAGE_CACHE_SIZE - 1); - if (!pg_offset) + if (!pg_offset) { + done = 1; break; + } } else pg_offset = PAGE_CACHE_SIZE; @@ -585,6 +563,7 @@ xfs_probe_unmapped_cluster( } total += len; + tindex++; } pagevec_release(&pvec); @@ -638,19 +617,19 @@ xfs_convert_page( struct inode *inode, struct page *page, loff_t tindex, - xfs_iomap_t *iomapp, + xfs_iomap_t *mp, xfs_ioend_t **ioendp, struct writeback_control *wbc, int startio, int all_bh) { struct buffer_head *bh, *head; - xfs_iomap_t *mp = iomapp, *tmp; 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; + xfs_off_t f_offset = page_offset(page); if (page->index != tindex) goto fail; @@ -703,15 +682,15 @@ xfs_convert_page( } continue; } - tmp = xfs_offset_to_map(page, mp, p_offset); - if (!tmp) { + + if (!xfs_iomap_valid(mp, f_offset + p_offset)) { done = 1; continue; } - ASSERT(!(tmp->iomap_flags & IOMAP_HOLE)); - ASSERT(!(tmp->iomap_flags & IOMAP_DELAY)); + ASSERT(!(mp->iomap_flags & IOMAP_HOLE)); + ASSERT(!(mp->iomap_flags & IOMAP_DELAY)); - xfs_map_at_offset(page, bh, p_offset, bbits, tmp, *ioendp); + xfs_map_at_offset(bh, f_offset + p_offset, bbits, mp); if (startio) { xfs_add_to_ioend(inode, bh, p_offset, type, ioendp, done); @@ -805,15 +784,14 @@ xfs_page_state_convert( 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; + int flags, len, err, iomap_valid = 0, uptodate = 1; int page_dirty, count = 0, trylock_flag = 0; /* wait for other IO threads? */ @@ -854,11 +832,9 @@ xfs_page_state_convert( 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); - /* TODO: fix up "done" variable and iomap pointer (boolean) */ /* TODO: cleanup count and page_dirty */ do { @@ -867,14 +843,16 @@ xfs_page_state_convert( 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 @@ -894,22 +872,20 @@ xfs_page_state_convert( flags |= trylock_flag; } - if (!iomp) { - done = 1; + if (!iomap_valid) { err = xfs_map_blocks(inode, offset, len, &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); + type, &ioend, + !iomap_valid); } else { set_buffer_dirty(bh); unlock_buffer(bh); @@ -917,8 +893,6 @@ xfs_page_state_convert( } page_dirty--; count++; - } else { - done = 1; } } else if ((buffer_uptodate(bh) || PageUptodate(page)) && (unmapped || startio)) { @@ -931,7 +905,7 @@ xfs_page_state_convert( * was found, and we are in a path where we * need to write the whole page out. */ - if (!iomp) { + if (!iomap_valid) { int size; size = xfs_probe_unmapped_cluster( @@ -939,21 +913,19 @@ xfs_page_state_convert( err = xfs_map_blocks(inode, offset, size, &iomap, BMAPI_WRITE|BMAPI_MMAP); - if (err) { + 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); + &ioend, !iomap_valid); } else { set_buffer_dirty(bh); unlock_buffer(bh); @@ -961,8 +933,6 @@ xfs_page_state_convert( } page_dirty--; count++; - } else { - done = 1; } } else if (startio) { if (buffer_uptodate(bh) && @@ -970,14 +940,14 @@ xfs_page_state_convert( ASSERT(buffer_mapped(bh)); xfs_add_to_ioend(inode, bh, p_offset, type, - &ioend, done); + &ioend, !iomap_valid); page_dirty--; count++; } else { - done = 1; + iomap_valid = 0; } } else { - done = 1; + iomap_valid = 0; } } @@ -992,11 +962,11 @@ xfs_page_state_convert( 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, + xfs_cluster_write(inode, page->index + 1, &iomap, &ioend, wbc, startio, unmapped, tlast); } -- 2.7.4