diff options
-rw-r--r-- | drivers/md/bitmap.c | 213 | ||||
-rw-r--r-- | drivers/md/bitmap.h | 7 |
2 files changed, 118 insertions, 102 deletions
diff --git a/drivers/md/bitmap.c b/drivers/md/bitmap.c index 17e2b472e16..c7784a98567 100644 --- a/drivers/md/bitmap.c +++ b/drivers/md/bitmap.c @@ -883,6 +883,8 @@ void bitmap_unplug(struct bitmap *bitmap) need_write = test_page_attr(bitmap, page, BITMAP_PAGE_NEEDWRITE); clear_page_attr(bitmap, page, BITMAP_PAGE_DIRTY); clear_page_attr(bitmap, page, BITMAP_PAGE_NEEDWRITE); + if (dirty || need_write) + clear_page_attr(bitmap, page, BITMAP_PAGE_PENDING); if (dirty) wait = 1; spin_unlock_irqrestore(&bitmap->lock, flags); @@ -1086,6 +1088,17 @@ static void bitmap_count_page(struct bitmap *bitmap, sector_t offset, int inc) bitmap->bp[page].count += inc; bitmap_checkfree(bitmap, page); } + +static void bitmap_set_pending(struct bitmap *bitmap, sector_t offset) +{ + sector_t chunk = offset >> bitmap->chunkshift; + unsigned long page = chunk >> PAGE_COUNTER_SHIFT; + struct bitmap_page *bp = &bitmap->bp[page]; + + if (!bp->pending) + bp->pending = 1; +} + static bitmap_counter_t *bitmap_get_counter(struct bitmap *bitmap, sector_t offset, sector_t *blocks, int create); @@ -1099,8 +1112,8 @@ void bitmap_daemon_work(struct mddev *mddev) { struct bitmap *bitmap; unsigned long j; + unsigned long nextpage; unsigned long flags; - struct page *page = NULL, *lastpage = NULL; sector_t blocks; void *paddr; @@ -1124,114 +1137,120 @@ void bitmap_daemon_work(struct mddev *mddev) } bitmap->allclean = 1; + /* Any file-page which is PENDING now needs to be written. + * So set NEEDWRITE now, then after we make any last-minute changes + * we will write it. + */ spin_lock_irqsave(&bitmap->lock, flags); + if (!bitmap->filemap) + /* error or shutdown */ + goto out; + + for (j = 0; j < bitmap->file_pages; j++) + if (test_page_attr(bitmap, bitmap->filemap[j], + BITMAP_PAGE_PENDING)) { + set_page_attr(bitmap, bitmap->filemap[j], + BITMAP_PAGE_NEEDWRITE); + clear_page_attr(bitmap, bitmap->filemap[j], + BITMAP_PAGE_PENDING); + } + + if (bitmap->need_sync && + mddev->bitmap_info.external == 0) { + /* Arrange for superblock update as well as + * other changes */ + bitmap_super_t *sb; + bitmap->need_sync = 0; + sb = kmap_atomic(bitmap->sb_page); + sb->events_cleared = + cpu_to_le64(bitmap->events_cleared); + kunmap_atomic(sb); + set_page_attr(bitmap, bitmap->sb_page, BITMAP_PAGE_NEEDWRITE); + } + /* Now look at the bitmap counters and if any are '2' or '1', + * decrement and handle accordingly. + */ + nextpage = 0; for (j = 0; j < bitmap->chunks; j++) { bitmap_counter_t *bmc; - if (!bitmap->filemap) - /* error or shutdown */ - break; - page = filemap_get_page(bitmap, j); - - if (page != lastpage) { - /* skip this page unless it's marked as needing cleaning */ - if (!test_page_attr(bitmap, page, BITMAP_PAGE_PENDING)) { - int need_write = test_page_attr(bitmap, page, - BITMAP_PAGE_NEEDWRITE); - if (need_write) - clear_page_attr(bitmap, page, BITMAP_PAGE_NEEDWRITE); - - spin_unlock_irqrestore(&bitmap->lock, flags); - if (need_write) - write_page(bitmap, page, 0); - spin_lock_irqsave(&bitmap->lock, flags); - j |= (PAGE_BITS - 1); + if (j == nextpage) { + nextpage += PAGE_COUNTER_RATIO; + if (!bitmap->bp[j >> PAGE_COUNTER_SHIFT].pending) { + j |= PAGE_COUNTER_MASK; continue; } - - /* grab the new page, sync and release the old */ - if (lastpage != NULL) { - if (test_page_attr(bitmap, lastpage, - BITMAP_PAGE_NEEDWRITE)) { - clear_page_attr(bitmap, lastpage, - BITMAP_PAGE_NEEDWRITE); - spin_unlock_irqrestore(&bitmap->lock, flags); - write_page(bitmap, lastpage, 0); - } else { - set_page_attr(bitmap, lastpage, - BITMAP_PAGE_NEEDWRITE); - bitmap->allclean = 0; - spin_unlock_irqrestore(&bitmap->lock, flags); - } - } else - spin_unlock_irqrestore(&bitmap->lock, flags); - lastpage = page; - - /* We are possibly going to clear some bits, so make - * sure that events_cleared is up-to-date. - */ - if (bitmap->need_sync && - mddev->bitmap_info.external == 0) { - bitmap_super_t *sb; - bitmap->need_sync = 0; - sb = kmap_atomic(bitmap->sb_page); - sb->events_cleared = - cpu_to_le64(bitmap->events_cleared); - kunmap_atomic(sb); - write_page(bitmap, bitmap->sb_page, 1); - } - spin_lock_irqsave(&bitmap->lock, flags); - if (!bitmap->need_sync) - clear_page_attr(bitmap, page, BITMAP_PAGE_PENDING); - else - bitmap->allclean = 0; + bitmap->bp[j >> PAGE_COUNTER_SHIFT].pending = 0; } bmc = bitmap_get_counter(bitmap, (sector_t)j << bitmap->chunkshift, &blocks, 0); - if (!bmc) + + if (!bmc) { j |= PAGE_COUNTER_MASK; - else if (*bmc) { - if (*bmc == 1 && !bitmap->need_sync) { - /* we can clear the bit */ - *bmc = 0; - bitmap_count_page(bitmap, - (sector_t)j << bitmap->chunkshift, - -1); - - /* clear the bit */ - paddr = kmap_atomic(page); - if (bitmap->flags & BITMAP_HOSTENDIAN) - clear_bit(file_page_offset(bitmap, j), - paddr); - else - __clear_bit_le( - file_page_offset(bitmap, - j), - paddr); - kunmap_atomic(paddr); - } else if (*bmc <= 2) { - *bmc = 1; /* maybe clear the bit next time */ - set_page_attr(bitmap, page, BITMAP_PAGE_PENDING); + continue; + } + if (*bmc == 1 && !bitmap->need_sync) { + /* We can clear the bit */ + struct page *page; + *bmc = 0; + bitmap_count_page( + bitmap, + (sector_t)j << bitmap->chunkshift, + -1); + + page = filemap_get_page(bitmap, j); + paddr = kmap_atomic(page); + if (bitmap->flags & BITMAP_HOSTENDIAN) + clear_bit(file_page_offset(bitmap, j), + paddr); + else + __clear_bit_le(file_page_offset(bitmap, j), + paddr); + kunmap_atomic(paddr); + if (!test_page_attr(bitmap, page, + BITMAP_PAGE_NEEDWRITE)) { + set_page_attr(bitmap, page, + BITMAP_PAGE_PENDING); bitmap->allclean = 0; } + } else if (*bmc && *bmc <= 2) { + *bmc = 1; + bitmap_set_pending( + bitmap, + (sector_t)j << bitmap->chunkshift); + bitmap->allclean = 0; } } - spin_unlock_irqrestore(&bitmap->lock, flags); - /* now sync the final page */ - if (lastpage != NULL) { - spin_lock_irqsave(&bitmap->lock, flags); - if (test_page_attr(bitmap, lastpage, BITMAP_PAGE_NEEDWRITE)) { - clear_page_attr(bitmap, lastpage, BITMAP_PAGE_NEEDWRITE); - spin_unlock_irqrestore(&bitmap->lock, flags); - write_page(bitmap, lastpage, 0); - } else { - set_page_attr(bitmap, lastpage, BITMAP_PAGE_NEEDWRITE); - bitmap->allclean = 0; + /* Now start writeout on any page in NEEDWRITE that isn't DIRTY. + * DIRTY pages need to be written by bitmap_unplug so it can wait + * for them. + * If we find any DIRTY page we stop there and let bitmap_unplug + * handle all the rest. This is important in the case where + * the first blocking holds the superblock and it has been updated. + * We mustn't write any other blocks before the superblock. + */ + for (j = 0; j < bitmap->file_pages; j++) { + struct page *page = bitmap->filemap[j]; + + if (test_page_attr(bitmap, page, + BITMAP_PAGE_DIRTY)) + /* bitmap_unplug will handle the rest */ + break; + if (test_page_attr(bitmap, page, + BITMAP_PAGE_NEEDWRITE)) { + clear_page_attr(bitmap, page, + BITMAP_PAGE_NEEDWRITE); spin_unlock_irqrestore(&bitmap->lock, flags); + write_page(bitmap, page, 0); + spin_lock_irqsave(&bitmap->lock, flags); + if (!bitmap->filemap) + break; } } +out: + spin_unlock_irqrestore(&bitmap->lock, flags); done: if (bitmap->allclean == 0) @@ -1386,11 +1405,7 @@ void bitmap_endwrite(struct bitmap *bitmap, sector_t offset, unsigned long secto (*bmc)--; if (*bmc <= 2) { - set_page_attr(bitmap, - filemap_get_page( - bitmap, - offset >> bitmap->chunkshift), - BITMAP_PAGE_PENDING); + bitmap_set_pending(bitmap, offset); bitmap->allclean = 0; } spin_unlock_irqrestore(&bitmap->lock, flags); @@ -1476,9 +1491,7 @@ void bitmap_end_sync(struct bitmap *bitmap, sector_t offset, sector_t *blocks, i *bmc |= NEEDED_MASK; else { if (*bmc <= 2) { - set_page_attr(bitmap, - filemap_get_page(bitmap, offset >> bitmap->chunkshift), - BITMAP_PAGE_PENDING); + bitmap_set_pending(bitmap, offset); bitmap->allclean = 0; } } @@ -1551,11 +1564,9 @@ static void bitmap_set_memory_bits(struct bitmap *bitmap, sector_t offset, int n return; } if (!*bmc) { - struct page *page; *bmc = 2 | (needed ? NEEDED_MASK : 0); bitmap_count_page(bitmap, offset, 1); - page = filemap_get_page(bitmap, offset >> bitmap->chunkshift); - set_page_attr(bitmap, page, BITMAP_PAGE_PENDING); + bitmap_set_pending(bitmap, offset); bitmap->allclean = 0; } spin_unlock_irq(&bitmap->lock); diff --git a/drivers/md/bitmap.h b/drivers/md/bitmap.h index b44b0aba2d4..79e17983473 100644 --- a/drivers/md/bitmap.h +++ b/drivers/md/bitmap.h @@ -160,9 +160,14 @@ struct bitmap_page { */ unsigned int hijacked:1; /* + * If any counter in this page is '1' or '2' - and so could be + * cleared then that page is marked as 'pending' + */ + unsigned int pending:1; + /* * count of dirty bits on the page */ - unsigned int count:31; + unsigned int count:30; }; /* the main bitmap structure - one per mddev */ |