diff options
Diffstat (limited to 'fs/btrfs/extent_map.c')
| -rw-r--r-- | fs/btrfs/extent_map.c | 672 |
1 files changed, 656 insertions, 16 deletions
diff --git a/fs/btrfs/extent_map.c b/fs/btrfs/extent_map.c index 0ab368e091f9..55fefdfab84c 100644 --- a/fs/btrfs/extent_map.c +++ b/fs/btrfs/extent_map.c @@ -26,16 +26,6 @@ struct tree_entry { struct rb_node rb_node; }; -/* bits for the extent state */ -#define EXTENT_DIRTY 1 -#define EXTENT_WRITEBACK (1 << 1) -#define EXTENT_UPTODATE (1 << 2) -#define EXTENT_LOCKED (1 << 3) -#define EXTENT_NEW (1 << 4) -#define EXTENT_DELALLOC (1 << 5) - -#define EXTENT_IOBITS (EXTENT_LOCKED | EXTENT_WRITEBACK) - void __init extent_map_init(void) { extent_map_cache = btrfs_cache_create("extent_map", @@ -223,7 +213,8 @@ int add_extent_mapping(struct extent_map_tree *tree, if (rb) prev = rb_entry(rb, struct extent_map, rb_node); if (prev && prev->end + 1 == em->start && - ((em->block_start == 0 && prev->block_start == 0) || + ((em->block_start == EXTENT_MAP_HOLE && + prev->block_start == EXTENT_MAP_HOLE) || (em->block_start == prev->block_end + 1))) { em->start = prev->start; em->block_start = prev->block_start; @@ -926,6 +917,40 @@ int set_range_writeback(struct extent_map_tree *tree, u64 start, u64 end) } EXPORT_SYMBOL(set_range_writeback); +int find_first_extent_bit(struct extent_map_tree *tree, u64 start, + u64 *start_ret, u64 *end_ret, int bits) +{ + struct rb_node *node; + struct extent_state *state; + int ret = 1; + + write_lock_irq(&tree->lock); + /* + * this search will find all the extents that end after + * our range starts. + */ + node = tree_search(&tree->state, start); + if (!node || IS_ERR(node)) { + goto out; + } + + while(1) { + state = rb_entry(node, struct extent_state, rb_node); + if (state->state & bits) { + *start_ret = state->start; + *end_ret = state->end; + ret = 0; + } + node = rb_next(node); + if (!node) + break; + } +out: + write_unlock_irq(&tree->lock); + return ret; +} +EXPORT_SYMBOL(find_first_extent_bit); + u64 find_lock_delalloc_range(struct extent_map_tree *tree, u64 start, u64 lock_start, u64 *end, u64 max_bytes) { @@ -1450,7 +1475,7 @@ int extent_read_full_page(struct extent_map_tree *tree, struct page *page, em = NULL; /* we've found a hole, just zero and go on */ - if (block_start == 0) { + if (block_start == EXTENT_MAP_HOLE) { zero_user_page(page, page_offset, iosize, KM_USER0); set_extent_uptodate(tree, cur, cur + iosize - 1, GFP_NOFS); @@ -1593,7 +1618,8 @@ int extent_write_full_page(struct extent_map_tree *tree, struct page *page, free_extent_map(em); em = NULL; - if (block_start == 0 || block_start == EXTENT_MAP_INLINE) { + if (block_start == EXTENT_MAP_HOLE || + block_start == EXTENT_MAP_INLINE) { clear_extent_dirty(tree, cur, cur + iosize - 1, GFP_NOFS); cur = cur + iosize; @@ -1630,7 +1656,6 @@ int extent_write_full_page(struct extent_map_tree *tree, struct page *page, nr++; } done: - WARN_ON(test_range_bit(tree, start, page_end, EXTENT_DIRTY, 0)); unlock_extent(tree, start, page_end, GFP_NOFS); unlock_page(page); return 0; @@ -1827,8 +1852,623 @@ sector_t extent_bmap(struct address_space *mapping, sector_t iblock, // XXX(hch): block 0 is valid in some cases, e.g. XFS RT device if (em->block_start == EXTENT_MAP_INLINE || - em->block_start == 0) - return 0; + em->block_start == EXTENT_MAP_HOLE) + return 0; return (em->block_start + start - em->start) >> inode->i_blkbits; } + +struct extent_buffer *alloc_extent_buffer(struct extent_map_tree *tree, + u64 start, unsigned long len, + gfp_t mask) +{ + unsigned long num_pages = ((start + len - 1) >> PAGE_CACHE_SHIFT) - + (start >> PAGE_CACHE_SHIFT) + 1; + unsigned long i; + unsigned long index = start >> PAGE_CACHE_SHIFT; + struct extent_buffer *eb; + struct page *p; + struct address_space *mapping = tree->mapping; + int uptodate = 0; + + eb = kzalloc(EXTENT_BUFFER_SIZE(num_pages), mask); + if (!eb || IS_ERR(eb)) + return NULL; + + eb->start = start; + eb->len = len; + atomic_set(&eb->refs, 1); + + for (i = 0; i < num_pages; i++, index++) { + p = find_or_create_page(mapping, index, mask | __GFP_HIGHMEM); + if (!p) + goto fail; + eb->pages[i] = p; + if (!PageUptodate(p)) + uptodate = 0; + unlock_page(p); + } + if (uptodate) + eb->flags |= EXTENT_UPTODATE; + return eb; +fail: + free_extent_buffer(eb); + return NULL; +} +EXPORT_SYMBOL(alloc_extent_buffer); + +struct extent_buffer *find_extent_buffer(struct extent_map_tree *tree, + u64 start, unsigned long len, + gfp_t mask) +{ + unsigned long num_pages = ((start + len - 1) >> PAGE_CACHE_SHIFT) - + (start >> PAGE_CACHE_SHIFT) + 1; + unsigned long i; + unsigned long index = start >> PAGE_CACHE_SHIFT; + struct extent_buffer *eb; + struct page *p; + struct address_space *mapping = tree->mapping; + + eb = kzalloc(EXTENT_BUFFER_SIZE(num_pages), mask); + if (!eb || IS_ERR(eb)) + return NULL; + + eb->start = start; + eb->len = len; + atomic_set(&eb->refs, 1); + + for (i = 0; i < num_pages; i++, index++) { + p = find_get_page(mapping, index); + if (!p) + goto fail; + eb->pages[i] = p; + } + return eb; +fail: + free_extent_buffer(eb); + return NULL; +} +EXPORT_SYMBOL(find_extent_buffer); + +void free_extent_buffer(struct extent_buffer *eb) +{ + unsigned long i; + unsigned long num_pages; + + if (!eb) + return; + + if (!atomic_dec_and_test(&eb->refs)) + return; + + num_pages = ((eb->start + eb->len - 1) >> PAGE_CACHE_SHIFT) - + (eb->start >> PAGE_CACHE_SHIFT) + 1; + + for (i = 0; i < num_pages; i++) { + if (eb->pages[i]) + page_cache_release(eb->pages[i]); + } + kfree(eb); +} +EXPORT_SYMBOL(free_extent_buffer); + +int clear_extent_buffer_dirty(struct extent_map_tree *tree, + struct extent_buffer *eb) +{ + int set; + unsigned long i; + unsigned long num_pages; + struct page *page; + + u64 start = eb->start; + u64 end = start + eb->len - 1; + + set = clear_extent_dirty(tree, start, end, GFP_NOFS); + num_pages = ((eb->start + eb->len - 1) >> PAGE_CACHE_SHIFT) - + (eb->start >> PAGE_CACHE_SHIFT) + 1; + + for (i = 0; i < num_pages; i++) { + page = eb->pages[i]; + lock_page(page); + /* + * if we're on the last page or the first page and the + * block isn't aligned on a page boundary, do extra checks + * to make sure we don't clean page that is partially dirty + */ + if ((i == 0 && (eb->start & (PAGE_CACHE_SIZE - 1))) || + ((i == num_pages - 1) && + ((eb->start + eb->len - 1) & (PAGE_CACHE_SIZE - 1)))) { + start = page->index << PAGE_CACHE_SHIFT; + end = start + PAGE_CACHE_SIZE - 1; + if (test_range_bit(tree, start, end, + EXTENT_DIRTY, 0)) { + unlock_page(page); + continue; + } + } + clear_page_dirty_for_io(page); + unlock_page(page); + } + return 0; +} +EXPORT_SYMBOL(clear_extent_buffer_dirty); + +int wait_on_extent_buffer_writeback(struct extent_map_tree *tree, + struct extent_buffer *eb) +{ + return wait_on_extent_writeback(tree, eb->start, + eb->start + eb->len - 1); +} +EXPORT_SYMBOL(wait_on_extent_buffer_writeback); + +int set_extent_buffer_dirty(struct extent_map_tree *tree, + struct extent_buffer *eb) +{ + return set_range_dirty(tree, eb->start, eb->start + eb->len - 1); +} +EXPORT_SYMBOL(set_extent_buffer_dirty); + +int set_extent_buffer_uptodate(struct extent_map_tree *tree, + struct extent_buffer *eb) +{ + unsigned long i; + struct page *page; + unsigned long num_pages; + + num_pages = ((eb->start + eb->len - 1) >> PAGE_CACHE_SHIFT) - + (eb->start >> PAGE_CACHE_SHIFT) + 1; + + set_extent_uptodate(tree, eb->start, eb->start + eb->len - 1, + GFP_NOFS); + for (i = 0; i < num_pages; i++) { + page = eb->pages[i]; + if ((i == 0 && (eb->start & (PAGE_CACHE_SIZE - 1))) || + ((i == num_pages - 1) && + ((eb->start + eb->len - 1) & (PAGE_CACHE_SIZE - 1)))) { + check_page_uptodate(tree, page); + continue; + } + SetPageUptodate(page); + } + return 0; +} +EXPORT_SYMBOL(set_extent_buffer_uptodate); + +int extent_buffer_uptodate(struct extent_map_tree *tree, + struct extent_buffer *eb) +{ + if (eb->flags & EXTENT_UPTODATE) + return 1; + return test_range_bit(tree, eb->start, eb->start + eb->len - 1, + EXTENT_UPTODATE, 1); +} +EXPORT_SYMBOL(extent_buffer_uptodate); + +int read_extent_buffer_pages(struct extent_map_tree *tree, + struct extent_buffer *eb, int wait) +{ + unsigned long i; + struct page *page; + int err; + int ret = 0; + unsigned long num_pages; + + if (eb->flags & EXTENT_UPTODATE) + return 0; + + if (test_range_bit(tree, eb->start, eb->start + eb->len - 1, + EXTENT_UPTODATE, 1)) { + return 0; + } + + num_pages = ((eb->start + eb->len - 1) >> PAGE_CACHE_SHIFT) - + (eb->start >> PAGE_CACHE_SHIFT) + 1; + for (i = 0; i < num_pages; i++) { + page = eb->pages[i]; + if (PageUptodate(page)) { + continue; + } + if (!wait) { + if (TestSetPageLocked(page)) { + continue; + } + } else { + lock_page(page); + } + if (!PageUptodate(page)) { + err = page->mapping->a_ops->readpage(NULL, page); + if (err) { + ret = err; + } + } else { + unlock_page(page); + } + } + + if (ret || !wait) { + return ret; + } + + for (i = 0; i < num_pages; i++) { + page = eb->pages[i]; + wait_on_page_locked(page); + if (!PageUptodate(page)) { + ret = -EIO; + } + } + eb->flags |= EXTENT_UPTODATE; + return ret; +} +EXPORT_SYMBOL(read_extent_buffer_pages); + +void read_extent_buffer(struct extent_buffer *eb, void *dstv, + unsigned long start, + unsigned long len) +{ + size_t cur; + size_t offset; + struct page *page; + char *kaddr; + char *dst = (char *)dstv; + size_t start_offset = eb->start & ((u64)PAGE_CACHE_SIZE - 1); + unsigned long i = (start_offset + start) >> PAGE_CACHE_SHIFT; + + WARN_ON(start > eb->len); + WARN_ON(start + len > eb->start + eb->len); + + page = eb->pages[i]; + offset = start & ((unsigned long)PAGE_CACHE_SIZE - 1); + if (i == 0) + offset += start_offset; + + while(len > 0) { + WARN_ON(!PageUptodate(page)); + + cur = min(len, (PAGE_CACHE_SIZE - offset)); + // kaddr = kmap_atomic(page, KM_USER0); + kaddr = page_address(page); + memcpy(dst, kaddr + offset, cur); + // kunmap_atomic(kaddr, KM_USER0); + + dst += cur; + len -= cur; + offset = 0; + i++; + page = eb->pages[i]; + } +} +EXPORT_SYMBOL(read_extent_buffer); + +int map_extent_buffer(struct extent_buffer *eb, unsigned long start, + char **token, char **map, + unsigned long *map_start, + unsigned long *map_len, int km) +{ + size_t offset; + char *kaddr; + size_t start_offset = eb->start & ((u64)PAGE_CACHE_SIZE - 1); + unsigned long i = (start_offset + start) >> PAGE_CACHE_SHIFT; + + WARN_ON(start > eb->len); + + if (i == 0) { + offset = start_offset; + *map_start = 0; + } else { + offset = 0; + *map_start = (i << PAGE_CACHE_SHIFT) - offset; + } + + // kaddr = kmap_atomic(eb->pages[i], km); + kaddr = page_address(eb->pages[i]); + *token = kaddr; + *map = kaddr + offset; + *map_len = PAGE_CACHE_SIZE - offset; + return 0; +} +EXPORT_SYMBOL(map_extent_buffer); + +void unmap_extent_buffer(struct extent_buffer *eb, char *token, int km) +{ + // kunmap_atomic(token, km); +} +EXPORT_SYMBOL(unmap_extent_buffer); + +int memcmp_extent_buffer(struct extent_buffer *eb, const void *ptrv, + unsigned long start, + unsigned long len) +{ + size_t cur; + size_t offset; + struct page *page; + char *kaddr; + char *ptr = (char *)ptrv; + size_t start_offset = eb->start & ((u64)PAGE_CACHE_SIZE - 1); + unsigned long i = (start_offset + start) >> PAGE_CACHE_SHIFT; + int ret = 0; + + WARN_ON(start > eb->len); + WARN_ON(start + len > eb->start + eb->len); + + page = eb->pages[i]; + offset = start & ((unsigned long)PAGE_CACHE_SIZE - 1); + if (i == 0) + offset += start_offset; + + while(len > 0) { + WARN_ON(!PageUptodate(page)); + + cur = min(len, (PAGE_CACHE_SIZE - offset)); + + // kaddr = kmap_atomic(page, KM_USER0); + kaddr = page_address(page); + ret = memcmp(ptr, kaddr + offset, cur); + // kunmap_atomic(kaddr, KM_USER0); + if (ret) + break; + + ptr += cur; + len -= cur; + offset = 0; + i++; + page = eb->pages[i]; + } + return ret; +} +EXPORT_SYMBOL(memcmp_extent_buffer); + +void write_extent_buffer(struct extent_buffer *eb, const void *srcv, + unsigned long start, unsigned long len) +{ + size_t cur; + size_t offset; + struct page *page; + char *kaddr; + char *src = (char *)srcv; + size_t start_offset = eb->start & ((u64)PAGE_CACHE_SIZE - 1); + unsigned long i = (start_offset + start) >> PAGE_CACHE_SHIFT; + + WARN_ON(start > eb->len); + WARN_ON(start + len > eb->start + eb->len); + + page = eb->pages[i]; + offset = start & ((unsigned long)PAGE_CACHE_SIZE - 1); + if (i == 0) + offset += start_offset; + + while(len > 0) { + WARN_ON(!PageUptodate(page)); + + cur = min(len, PAGE_CACHE_SIZE - offset); + // kaddr = kmap_atomic(page, KM_USER0); + kaddr = page_address(page); + memcpy(kaddr + offset, src, cur); + // kunmap_atomic(kaddr, KM_USER0); + + src += cur; + len -= cur; + offset = 0; + i++; + page = eb->pages[i]; + } +} +EXPORT_SYMBOL(write_extent_buffer); + +void memset_extent_buffer(struct extent_buffer *eb, char c, + unsigned long start, unsigned long len) +{ + size_t cur; + size_t offset; + struct page *page; + char *kaddr; + size_t start_offset = eb->start & ((u64)PAGE_CACHE_SIZE - 1); + unsigned long i = (start_offset + start) >> PAGE_CACHE_SHIFT; + + WARN_ON(start > eb->len); + WARN_ON(start + len > eb->start + eb->len); + + page = eb->pages[i]; + offset = start & ((unsigned long)PAGE_CACHE_SIZE - 1); + if (i == 0) + offset += start_offset; + + while(len > 0) { + WARN_ON(!PageUptodate(page)); + + cur = min(len, PAGE_CACHE_SIZE - offset); + // kaddr = kmap_atomic(page, KM_USER0); + kaddr = page_address(page); + memset(kaddr + offset, c, cur); + // kunmap_atomic(kaddr, KM_USER0); + + len -= cur; + offset = 0; + i++; + page = eb->pages[i]; + } +} +EXPORT_SYMBOL(memset_extent_buffer); + +void copy_extent_buffer(struct extent_buffer *dst, struct extent_buffer *src, + unsigned long dst_offset, unsigned long src_offset, + unsigned long len) +{ + u64 dst_len = dst->len; + size_t cur; + size_t offset; + struct page *page; + char *kaddr; + size_t start_offset = dst->start & ((u64)PAGE_CACHE_SIZE - 1); + unsigned long i = (start_offset + dst_offset) >> PAGE_CACHE_SHIFT; + + WARN_ON(src->len != dst_len); + + offset = dst_offset & ((unsigned long)PAGE_CACHE_SIZE - 1); + if (i == 0) + offset += start_offset; + + while(len > 0) { + page = dst->pages[i]; + WARN_ON(!PageUptodate(page)); + + cur = min(len, (unsigned long)(PAGE_CACHE_SIZE - offset)); + + // kaddr = kmap_atomic(page, KM_USER1); + kaddr = page_address(page); + read_extent_buffer(src, kaddr + offset, src_offset, cur); + // kunmap_atomic(kaddr, KM_USER1); + + src_offset += cur; + len -= cur; + offset = 0; + i++; + } +} +EXPORT_SYMBOL(copy_extent_buffer); + +static void move_pages(struct page *dst_page, struct page *src_page, + unsigned long dst_off, unsigned long src_off, + unsigned long len) +{ + // char *dst_kaddr = kmap_atomic(dst_page, KM_USER0); + char *dst_kaddr = page_address(dst_page); + if (dst_page == src_page) { + memmove(dst_kaddr + dst_off, dst_kaddr + src_off, len); + } else { + // char *src_kaddr = kmap_atomic(src_page, KM_USER1); + char *src_kaddr = page_address(src_page); + char *p = dst_kaddr + dst_off + len; + char *s = src_kaddr + src_off + len; + + while (len--) + *--p = *--s; + + // kunmap_atomic(src_kaddr, KM_USER1); + } + // kunmap_atomic(dst_kaddr, KM_USER0); +} + +static void copy_pages(struct page *dst_page, struct page *src_page, + unsigned long dst_off, unsigned long src_off, + unsigned long len) +{ + //kmap_atomic(dst_page, KM_USER0); + char *dst_kaddr = page_address(dst_page); + char *src_kaddr; + + if (dst_page != src_page) + src_kaddr = page_address(src_page); // kmap_atomic(src_page, KM_USER1); + else + src_kaddr = dst_kaddr; + + memcpy(dst_kaddr + dst_off, src_kaddr + src_off, len); + /* + kunmap_atomic(dst_kaddr, KM_USER0); + if (dst_page != src_page) + kunmap_atomic(src_kaddr, KM_USER1); + */ +} + +void memcpy_extent_buffer(struct extent_buffer *dst, unsigned long dst_offset, + unsigned long src_offset, unsigned long len) +{ + size_t cur; + size_t dst_off_in_page; + size_t src_off_in_page; + size_t start_offset = dst->start & ((u64)PAGE_CACHE_SIZE - 1); + unsigned long dst_i; + unsigned long src_i; + + if (src_offset + len > dst->len) { + printk("memmove bogus src_offset %lu move len %lu len %lu\n", + src_offset, len, dst->len); + BUG_ON(1); + } + if (dst_offset + len > dst->len) { + printk("memmove bogus dst_offset %lu move len %lu len %lu\n", + dst_offset, len, dst->len); + BUG_ON(1); + } + + while(len > 0) { + dst_off_in_page = dst_offset & + ((unsigned long)PAGE_CACHE_SIZE - 1); + src_off_in_page = src_offset & + ((unsigned long)PAGE_CACHE_SIZE - 1); + + dst_i = (start_offset + dst_offset) >> PAGE_CACHE_SHIFT; + src_i = (start_offset + src_offset) >> PAGE_CACHE_SHIFT; + + if (src_i == 0) + src_off_in_page += start_offset; + if (dst_i == 0) + dst_off_in_page += start_offset; + + cur = min(len, (unsigned long)(PAGE_CACHE_SIZE - + src_off_in_page)); + cur = min(cur, (unsigned long)(PAGE_CACHE_SIZE - + dst_off_in_page)); + + copy_pages(dst->pages[dst_i], dst->pages[src_i], + dst_off_in_page, src_off_in_page, cur); + + src_offset += cur; + dst_offset += cur; + len -= cur; + } +} +EXPORT_SYMBOL(memcpy_extent_buffer); + +void memmove_extent_buffer(struct extent_buffer *dst, unsigned long dst_offset, + unsigned long src_offset, unsigned long len) +{ + size_t cur; + size_t dst_off_in_page; + size_t src_off_in_page; + unsigned long dst_end = dst_offset + len - 1; + unsigned long src_end = src_offset + len - 1; + size_t start_offset = dst->start & ((u64)PAGE_CACHE_SIZE - 1); + unsigned long dst_i; + unsigned long src_i; + + if (src_offset + len > dst->len) { + printk("memmove bogus src_offset %lu move len %lu len %lu\n", + src_offset, len, dst->len); + BUG_ON(1); + } + if (dst_offset + len > dst->len) { + printk("memmove bogus dst_offset %lu move len %lu len %lu\n", + dst_offset, len, dst->len); + BUG_ON(1); + } + if (dst_offset < src_offset) { + memcpy_extent_buffer(dst, dst_offset, src_offset, len); + return; + } + while(len > 0) { + dst_i = (start_offset + dst_end) >> PAGE_CACHE_SHIFT; + src_i = (start_offset + src_end) >> PAGE_CACHE_SHIFT; + + dst_off_in_page = dst_end & + ((unsigned long)PAGE_CACHE_SIZE - 1); + src_off_in_page = src_end & + ((unsigned long)PAGE_CACHE_SIZE - 1); + + if (src_i == 0) + src_off_in_page += start_offset; + if (dst_i == 0) + dst_off_in_page += start_offset; + + cur = min(len, src_off_in_page + 1); + cur = min(cur, dst_off_in_page + 1); +// printk("move pages orig dst %lu src %lu len %lu, this %lu %lu %lu\n", dst_offset, src_offset, len, dst_off_in_page - cur + 1, src_off_in_page - cur + 1, cur); + move_pages(dst->pages[dst_i], dst->pages[src_i], + dst_off_in_page - cur + 1, + src_off_in_page - cur + 1, cur); + + dst_end -= cur - 1; + src_end -= cur - 1; + len -= cur; + } +} +EXPORT_SYMBOL(memmove_extent_buffer); |