diff options
Diffstat (limited to 'fs/btrfs/inode.c')
-rw-r--r-- | fs/btrfs/inode.c | 584 |
1 files changed, 539 insertions, 45 deletions
diff --git a/fs/btrfs/inode.c b/fs/btrfs/inode.c index bf4bed6ca4d..9797592dc86 100644 --- a/fs/btrfs/inode.c +++ b/fs/btrfs/inode.c @@ -49,6 +49,7 @@ #include "compat.h" #include "tree-log.h" #include "ref-cache.h" +#include "compression.h" struct btrfs_iget_args { u64 ino; @@ -83,6 +84,7 @@ static unsigned char btrfs_type_by_mode[S_IFMT >> S_SHIFT] = { }; static void btrfs_truncate(struct inode *inode); +static int btrfs_finish_ordered_io(struct inode *inode, u64 start, u64 end); /* * a very lame attempt at stopping writes when the FS is 85% full. There @@ -114,57 +116,374 @@ int btrfs_check_free_space(struct btrfs_root *root, u64 num_required, } /* + * this does all the hard work for inserting an inline extent into + * the btree. The caller should have done a btrfs_drop_extents so that + * no overlapping inline items exist in the btree + */ +static int noinline insert_inline_extent(struct btrfs_trans_handle *trans, + struct btrfs_root *root, struct inode *inode, + u64 start, size_t size, size_t compressed_size, + struct page **compressed_pages) +{ + struct btrfs_key key; + struct btrfs_path *path; + struct extent_buffer *leaf; + struct page *page = NULL; + char *kaddr; + unsigned long ptr; + struct btrfs_file_extent_item *ei; + int err = 0; + int ret; + size_t cur_size = size; + size_t datasize; + unsigned long offset; + int use_compress = 0; + + if (compressed_size && compressed_pages) { + use_compress = 1; + cur_size = compressed_size; + } + + path = btrfs_alloc_path(); if (!path) + return -ENOMEM; + + btrfs_set_trans_block_group(trans, inode); + + key.objectid = inode->i_ino; + key.offset = start; + btrfs_set_key_type(&key, BTRFS_EXTENT_DATA_KEY); + inode_add_bytes(inode, size); + datasize = btrfs_file_extent_calc_inline_size(cur_size); + + inode_add_bytes(inode, size); + ret = btrfs_insert_empty_item(trans, root, path, &key, + datasize); + BUG_ON(ret); + if (ret) { + err = ret; + printk("got bad ret %d\n", ret); + goto fail; + } + leaf = path->nodes[0]; + ei = btrfs_item_ptr(leaf, path->slots[0], + struct btrfs_file_extent_item); + btrfs_set_file_extent_generation(leaf, ei, trans->transid); + btrfs_set_file_extent_type(leaf, ei, BTRFS_FILE_EXTENT_INLINE); + btrfs_set_file_extent_encryption(leaf, ei, 0); + btrfs_set_file_extent_other_encoding(leaf, ei, 0); + btrfs_set_file_extent_ram_bytes(leaf, ei, size); + ptr = btrfs_file_extent_inline_start(ei); + + if (use_compress) { + struct page *cpage; + int i = 0; + while(compressed_size > 0) { + cpage = compressed_pages[i]; + cur_size = min(compressed_size, + PAGE_CACHE_SIZE); + + kaddr = kmap(cpage); + write_extent_buffer(leaf, kaddr, ptr, cur_size); + kunmap(cpage); + + i++; + ptr += cur_size; + compressed_size -= cur_size; + } + btrfs_set_file_extent_compression(leaf, ei, + BTRFS_COMPRESS_ZLIB); + } else { + page = find_get_page(inode->i_mapping, + start >> PAGE_CACHE_SHIFT); + btrfs_set_file_extent_compression(leaf, ei, 0); + kaddr = kmap_atomic(page, KM_USER0); + offset = start & (PAGE_CACHE_SIZE - 1); + write_extent_buffer(leaf, kaddr + offset, ptr, size); + kunmap_atomic(kaddr, KM_USER0); + page_cache_release(page); + } + btrfs_mark_buffer_dirty(leaf); + btrfs_free_path(path); + + BTRFS_I(inode)->disk_i_size = inode->i_size; + btrfs_update_inode(trans, root, inode); + return 0; +fail: + btrfs_free_path(path); + return err; +} + + +/* + * conditionally insert an inline extent into the file. This + * does the checks required to make sure the data is small enough + * to fit as an inline extent. + */ +static int cow_file_range_inline(struct btrfs_trans_handle *trans, + struct btrfs_root *root, + struct inode *inode, u64 start, u64 end, + size_t compressed_size, + struct page **compressed_pages) +{ + u64 isize = i_size_read(inode); + u64 actual_end = min(end + 1, isize); + u64 inline_len = actual_end - start; + u64 aligned_end = (end + root->sectorsize - 1) & + ~((u64)root->sectorsize - 1); + u64 hint_byte; + u64 data_len = inline_len; + int ret; + + if (compressed_size) + data_len = compressed_size; + + if (start > 0 || + data_len >= BTRFS_MAX_INLINE_DATA_SIZE(root) || + (!compressed_size && + (actual_end & (root->sectorsize - 1)) == 0) || + end + 1 < isize || + data_len > root->fs_info->max_inline) { + return 1; + } + + mutex_lock(&BTRFS_I(inode)->extent_mutex); + ret = btrfs_drop_extents(trans, root, inode, start, + aligned_end, aligned_end, &hint_byte); + BUG_ON(ret); + + if (isize > actual_end) + inline_len = min_t(u64, isize, actual_end); + ret = insert_inline_extent(trans, root, inode, start, + inline_len, compressed_size, + compressed_pages); + BUG_ON(ret); + btrfs_drop_extent_cache(inode, start, aligned_end, 0); + mutex_unlock(&BTRFS_I(inode)->extent_mutex); + return 0; +} + +/* * when extent_io.c finds a delayed allocation range in the file, * the call backs end up in this code. The basic idea is to * allocate extents on disk for the range, and create ordered data structs * in ram to track those extents. + * + * locked_page is the page that writepage had locked already. We use + * it to make sure we don't do extra locks or unlocks. + * + * *page_started is set to one if we unlock locked_page and do everything + * required to start IO on it. It may be clean and already done with + * IO when we return. */ -static int cow_file_range(struct inode *inode, u64 start, u64 end) +static int cow_file_range(struct inode *inode, struct page *locked_page, + u64 start, u64 end, int *page_started) { struct btrfs_root *root = BTRFS_I(inode)->root; struct btrfs_trans_handle *trans; u64 alloc_hint = 0; u64 num_bytes; + unsigned long ram_size; + u64 orig_start; + u64 disk_num_bytes; u64 cur_alloc_size; u64 blocksize = root->sectorsize; - u64 orig_num_bytes; + u64 actual_end; struct btrfs_key ins; struct extent_map *em; struct extent_map_tree *em_tree = &BTRFS_I(inode)->extent_tree; int ret = 0; + struct page **pages = NULL; + unsigned long nr_pages; + unsigned long nr_pages_ret = 0; + unsigned long total_compressed = 0; + unsigned long total_in = 0; + unsigned long max_compressed = 128 * 1024; + unsigned long max_uncompressed = 256 * 1024; + int i; + int will_compress; trans = btrfs_join_transaction(root, 1); BUG_ON(!trans); btrfs_set_trans_block_group(trans, inode); + orig_start = start; + + /* + * compression made this loop a bit ugly, but the basic idea is to + * compress some pages but keep the total size of the compressed + * extent relatively small. If compression is off, this goto target + * is never used. + */ +again: + will_compress = 0; + nr_pages = (end >> PAGE_CACHE_SHIFT) - (start >> PAGE_CACHE_SHIFT) + 1; + nr_pages = min(nr_pages, (128 * 1024UL) / PAGE_CACHE_SIZE); + actual_end = min_t(u64, i_size_read(inode), end + 1); + total_compressed = actual_end - start; + + /* we want to make sure that amount of ram required to uncompress + * an extent is reasonable, so we limit the total size in ram + * of a compressed extent to 256k + */ + total_compressed = min(total_compressed, max_uncompressed); num_bytes = (end - start + blocksize) & ~(blocksize - 1); num_bytes = max(blocksize, num_bytes); - orig_num_bytes = num_bytes; + disk_num_bytes = num_bytes; + total_in = 0; + ret = 0; - if (alloc_hint == EXTENT_MAP_INLINE) - goto out; + /* we do compression for mount -o compress and when the + * inode has not been flagged as nocompress + */ + if (!btrfs_test_flag(inode, NOCOMPRESS) && + btrfs_test_opt(root, COMPRESS)) { + WARN_ON(pages); + pages = kmalloc(sizeof(struct page *) * nr_pages, GFP_NOFS); + + /* we want to make sure the amount of IO required to satisfy + * a random read is reasonably small, so we limit the size + * of a compressed extent to 128k + */ + ret = btrfs_zlib_compress_pages(inode->i_mapping, start, + total_compressed, pages, + nr_pages, &nr_pages_ret, + &total_in, + &total_compressed, + max_compressed); + + if (!ret) { + unsigned long offset = total_compressed & + (PAGE_CACHE_SIZE - 1); + struct page *page = pages[nr_pages_ret - 1]; + char *kaddr; + + /* zero the tail end of the last page, we might be + * sending it down to disk + */ + if (offset) { + kaddr = kmap_atomic(page, KM_USER0); + memset(kaddr + offset, 0, + PAGE_CACHE_SIZE - offset); + kunmap_atomic(kaddr, KM_USER0); + } + will_compress = 1; + } + } + if (start == 0) { + /* lets try to make an inline extent */ + if (ret || total_in < (end - start + 1)) { + /* we didn't compress the entire range, try + * to make an uncompressed inline extent. This + * is almost sure to fail, but maybe inline sizes + * will get bigger later + */ + ret = cow_file_range_inline(trans, root, inode, + start, end, 0, NULL); + } else { + ret = cow_file_range_inline(trans, root, inode, + start, end, + total_compressed, pages); + } + if (ret == 0) { + extent_clear_unlock_delalloc(inode, + &BTRFS_I(inode)->io_tree, + start, end, NULL, + 1, 1, 1); + *page_started = 1; + ret = 0; + goto free_pages_out; + } + } + + if (will_compress) { + /* + * we aren't doing an inline extent round the compressed size + * up to a block size boundary so the allocator does sane + * things + */ + total_compressed = (total_compressed + blocksize - 1) & + ~(blocksize - 1); + + /* + * one last check to make sure the compression is really a + * win, compare the page count read with the blocks on disk + */ + total_in = (total_in + PAGE_CACHE_SIZE - 1) & + ~(PAGE_CACHE_SIZE - 1); + if (total_compressed >= total_in) { + will_compress = 0; + } else { + disk_num_bytes = total_compressed; + num_bytes = total_in; + } + } + if (!will_compress && pages) { + /* + * the compression code ran but failed to make things smaller, + * free any pages it allocated and our page pointer array + */ + for (i = 0; i < nr_pages_ret; i++) { + page_cache_release(pages[i]); + } + kfree(pages); + pages = NULL; + total_compressed = 0; + nr_pages_ret = 0; + + /* flag the file so we don't compress in the future */ + btrfs_set_flag(inode, NOCOMPRESS); + } + + BUG_ON(disk_num_bytes > + btrfs_super_total_bytes(&root->fs_info->super_copy)); - BUG_ON(num_bytes > btrfs_super_total_bytes(&root->fs_info->super_copy)); mutex_lock(&BTRFS_I(inode)->extent_mutex); btrfs_drop_extent_cache(inode, start, start + num_bytes - 1, 0); mutex_unlock(&BTRFS_I(inode)->extent_mutex); - while(num_bytes > 0) { - cur_alloc_size = min(num_bytes, root->fs_info->max_extent); + while(disk_num_bytes > 0) { + unsigned long min_bytes; + + /* + * the max size of a compressed extent is pretty small, + * make the code a little less complex by forcing + * the allocator to find a whole compressed extent at once + */ + if (will_compress) + min_bytes = disk_num_bytes; + else + min_bytes = root->sectorsize; + + cur_alloc_size = min(disk_num_bytes, root->fs_info->max_extent); ret = btrfs_reserve_extent(trans, root, cur_alloc_size, - root->sectorsize, 0, alloc_hint, + min_bytes, 0, alloc_hint, (u64)-1, &ins, 1); if (ret) { WARN_ON(1); - goto out; + goto free_pages_out_fail; } em = alloc_extent_map(GFP_NOFS); em->start = start; - em->len = ins.offset; + + if (will_compress) { + ram_size = num_bytes; + em->len = num_bytes; + } else { + /* ramsize == disk size */ + ram_size = ins.offset; + em->len = ins.offset; + } + em->block_start = ins.objectid; + em->block_len = ins.offset; em->bdev = root->fs_info->fs_devices->latest_bdev; + mutex_lock(&BTRFS_I(inode)->extent_mutex); set_bit(EXTENT_FLAG_PINNED, &em->flags); + + if (will_compress) + set_bit(EXTENT_FLAG_COMPRESSED, &em->flags); + while(1) { spin_lock(&em_tree->lock); ret = add_extent_mapping(em_tree, em); @@ -174,26 +493,95 @@ static int cow_file_range(struct inode *inode, u64 start, u64 end) break; } btrfs_drop_extent_cache(inode, start, - start + ins.offset - 1, 0); + start + ram_size - 1, 0); } mutex_unlock(&BTRFS_I(inode)->extent_mutex); cur_alloc_size = ins.offset; ret = btrfs_add_ordered_extent(inode, start, ins.objectid, - ins.offset, 0); + ram_size, cur_alloc_size, 0, + will_compress); BUG_ON(ret); - if (num_bytes < cur_alloc_size) { - printk("num_bytes %Lu cur_alloc %Lu\n", num_bytes, + + if (disk_num_bytes < cur_alloc_size) { + printk("num_bytes %Lu cur_alloc %Lu\n", disk_num_bytes, cur_alloc_size); break; } + + if (will_compress) { + /* + * we're doing compression, we and we need to + * submit the compressed extents down to the device. + * + * We lock down all the file pages, clearing their + * dirty bits and setting them writeback. Everyone + * that wants to modify the page will wait on the + * ordered extent above. + * + * The writeback bits on the file pages are + * cleared when the compressed pages are on disk + */ + btrfs_end_transaction(trans, root); + + if (start <= page_offset(locked_page) && + page_offset(locked_page) < start + ram_size) { + *page_started = 1; + } + + extent_clear_unlock_delalloc(inode, + &BTRFS_I(inode)->io_tree, + start, + start + ram_size - 1, + NULL, 1, 1, 0); + + ret = btrfs_submit_compressed_write(inode, start, + ram_size, ins.objectid, + cur_alloc_size, pages, + nr_pages_ret); + + BUG_ON(ret); + trans = btrfs_join_transaction(root, 1); + if (start + ram_size < end) { + start += ram_size; + alloc_hint = ins.objectid + ins.offset; + /* pages will be freed at end_bio time */ + pages = NULL; + goto again; + } else { + /* we've written everything, time to go */ + break; + } + } + /* we're not doing compressed IO, don't unlock the first + * page (which the caller expects to stay locked), don't + * clear any dirty bits and don't set any writeback bits + */ + extent_clear_unlock_delalloc(inode, &BTRFS_I(inode)->io_tree, + start, start + ram_size - 1, + locked_page, 0, 0, 0); + disk_num_bytes -= cur_alloc_size; num_bytes -= cur_alloc_size; alloc_hint = ins.objectid + ins.offset; start += cur_alloc_size; } + + ret = 0; out: btrfs_end_transaction(trans, root); + return ret; + +free_pages_out_fail: + extent_clear_unlock_delalloc(inode, &BTRFS_I(inode)->io_tree, + start, end, locked_page, 0, 0, 0); +free_pages_out: + for (i = 0; i < nr_pages_ret; i++) + page_cache_release(pages[i]); + if (pages) + kfree(pages); + + goto out; } /* @@ -203,7 +591,8 @@ out: * If no cow copies or snapshots exist, we write directly to the existing * blocks on disk */ -static int run_delalloc_nocow(struct inode *inode, u64 start, u64 end) +static int run_delalloc_nocow(struct inode *inode, struct page *locked_page, + u64 start, u64 end, int *page_started) { u64 extent_start; u64 extent_end; @@ -260,6 +649,11 @@ again: extent_end = extent_start + extent_num_bytes; err = 0; + if (btrfs_file_extent_compression(leaf, item) || + btrfs_file_extent_encryption(leaf,item) || + btrfs_file_extent_other_encoding(leaf, item)) + goto not_found; + if (loops && start != extent_start) goto not_found; @@ -284,7 +678,8 @@ again: bytenr += btrfs_file_extent_offset(leaf, item); extent_num_bytes = min(end + 1, extent_end) - start; ret = btrfs_add_ordered_extent(inode, start, bytenr, - extent_num_bytes, 1); + extent_num_bytes, + extent_num_bytes, 1, 0); if (ret) { err = ret; goto out; @@ -300,7 +695,8 @@ again: not_found: btrfs_end_transaction(trans, root); btrfs_free_path(path); - return cow_file_range(inode, start, end); + return cow_file_range(inode, locked_page, start, end, + page_started); } out: WARN_ON(err); @@ -312,16 +708,19 @@ out: /* * extent_io.c call back to do delayed allocation processing */ -static int run_delalloc_range(struct inode *inode, u64 start, u64 end) +static int run_delalloc_range(struct inode *inode, struct page *locked_page, + u64 start, u64 end, int *page_started) { struct btrfs_root *root = BTRFS_I(inode)->root; int ret; if (btrfs_test_opt(root, NODATACOW) || btrfs_test_flag(inode, NODATACOW)) - ret = run_delalloc_nocow(inode, start, end); + ret = run_delalloc_nocow(inode, locked_page, start, end, + page_started); else - ret = cow_file_range(inode, start, end); + ret = cow_file_range(inode, locked_page, start, end, + page_started); return ret; } @@ -383,7 +782,8 @@ int btrfs_clear_bit_hook(struct inode *inode, u64 start, u64 end, * we don't create bios that span stripes or chunks */ int btrfs_merge_bio_hook(struct page *page, unsigned long offset, - size_t size, struct bio *bio) + size_t size, struct bio *bio, + unsigned long bio_flags) { struct btrfs_root *root = BTRFS_I(page->mapping->host)->root; struct btrfs_mapping_tree *map_tree; @@ -413,7 +813,7 @@ int btrfs_merge_bio_hook(struct page *page, unsigned long offset, * are inserted into the btree */ int __btrfs_submit_bio_hook(struct inode *inode, int rw, struct bio *bio, - int mirror_num) + int mirror_num, unsigned long bio_flags) { struct btrfs_root *root = BTRFS_I(inode)->root; int ret = 0; @@ -429,7 +829,7 @@ int __btrfs_submit_bio_hook(struct inode *inode, int rw, struct bio *bio, * or reading the csums from the tree before a read */ int btrfs_submit_bio_hook(struct inode *inode, int rw, struct bio *bio, - int mirror_num) + int mirror_num, unsigned long bio_flags) { struct btrfs_root *root = BTRFS_I(inode)->root; int ret = 0; @@ -444,11 +844,17 @@ int btrfs_submit_bio_hook(struct inode *inode, int rw, struct bio *bio, if (!(rw & (1 << BIO_RW))) { btrfs_lookup_bio_sums(root, inode, bio); + + if (bio_flags & EXTENT_BIO_COMPRESSED) { + return btrfs_submit_compressed_read(inode, bio, + mirror_num, bio_flags); + } + goto mapit; } return btrfs_wq_submit_bio(BTRFS_I(inode)->root->fs_info, inode, rw, bio, mirror_num, - __btrfs_submit_bio_hook); + bio_flags, __btrfs_submit_bio_hook); mapit: return btrfs_map_bio(root, rw, bio, mirror_num, 0); } @@ -539,7 +945,7 @@ out_page: * good idea. This causes problems because we want to make sure COW * properly happens and the data=ordered rules are followed. * - * In our case any range that doesn't have the EXTENT_ORDERED bit set + * In our case any range that doesn't have the ORDERED bit set * hasn't been properly setup for IO. We kick off an async process * to fix it up. The async helper will wait for ordered extents, set * the delalloc bit and make it safe to write the page. @@ -632,10 +1038,21 @@ static int btrfs_finish_ordered_io(struct inode *inode, u64 start, u64 end) btrfs_set_file_extent_disk_bytenr(leaf, extent_item, ordered_extent->start); btrfs_set_file_extent_disk_num_bytes(leaf, extent_item, - ordered_extent->len); + ordered_extent->disk_len); btrfs_set_file_extent_offset(leaf, extent_item, 0); + + if (test_bit(BTRFS_ORDERED_COMPRESSED, &ordered_extent->flags)) + btrfs_set_file_extent_compression(leaf, extent_item, 1); + else + btrfs_set_file_extent_compression(leaf, extent_item, 0); + btrfs_set_file_extent_encryption(leaf, extent_item, 0); + btrfs_set_file_extent_other_encoding(leaf, extent_item, 0); + + /* ram bytes = extent_num_bytes for now */ btrfs_set_file_extent_num_bytes(leaf, extent_item, ordered_extent->len); + btrfs_set_file_extent_ram_bytes(leaf, extent_item, + ordered_extent->len); btrfs_mark_buffer_dirty(leaf); btrfs_drop_extent_cache(inode, ordered_extent->file_offset, @@ -644,7 +1061,7 @@ static int btrfs_finish_ordered_io(struct inode *inode, u64 start, u64 end) mutex_unlock(&BTRFS_I(inode)->extent_mutex); ins.objectid = ordered_extent->start; - ins.offset = ordered_extent->len; + ins.offset = ordered_extent->disk_len; ins.type = BTRFS_EXTENT_ITEM_KEY; ret = btrfs_alloc_reserved_extent(trans, root, leaf->start, root->root_key.objectid, @@ -714,6 +1131,7 @@ int btrfs_io_failed_hook(struct bio *failed_bio, int ret; int rw; u64 logical; + unsigned long bio_flags = 0; ret = get_state_private(failure_tree, start, &private); if (ret) { @@ -738,6 +1156,8 @@ int btrfs_io_failed_hook(struct bio *failed_bio, } logical = start - em->start; logical = em->block_start + logical; + if (test_bit(EXTENT_FLAG_COMPRESSED, &em->flags)) + bio_flags = EXTENT_BIO_COMPRESSED; failrec->logical = logical; free_extent_map(em); set_extent_bits(failure_tree, start, end, EXTENT_LOCKED | @@ -781,7 +1201,8 @@ int btrfs_io_failed_hook(struct bio *failed_bio, rw = READ; BTRFS_I(inode)->io_tree.ops->submit_bio_hook(inode, rw, bio, - failrec->last_mirror); + failrec->last_mirror, + bio_flags); return 0; } @@ -1644,10 +2065,8 @@ search_again: item_end += btrfs_file_extent_num_bytes(leaf, fi); } else if (extent_type == BTRFS_FILE_EXTENT_INLINE) { - struct btrfs_item *item = btrfs_item_nr(leaf, - path->slots[0]); item_end += btrfs_file_extent_inline_len(leaf, - item); + fi); } item_end--; } @@ -1715,7 +2134,14 @@ search_again: root_owner = btrfs_header_owner(leaf); } } else if (extent_type == BTRFS_FILE_EXTENT_INLINE) { - if (!del_item) { + /* + * we can't truncate inline items that have had + * special encodings + */ + if (!del_item && + btrfs_file_extent_compression(leaf, fi) == 0 && + btrfs_file_extent_encryption(leaf, fi) == 0 && + btrfs_file_extent_other_encoding(leaf, fi) == 0) { u32 size = new_size - found_key.offset; if (root->ref_cows) { @@ -1926,7 +2352,8 @@ static int btrfs_setattr(struct dentry *dentry, struct iattr *attr) err = btrfs_insert_file_extent(trans, root, inode->i_ino, hole_start, 0, 0, - hole_size, 0); + hole_size, 0, hole_size, + 0, 0, 0); btrfs_drop_extent_cache(inode, hole_start, (u64)-1, 0); btrfs_check_file(root, inode); @@ -2894,11 +3321,50 @@ static int merge_extent_mapping(struct extent_map_tree *em_tree, start_diff = map_start - em->start; em->start = map_start; em->len = map_len; - if (em->block_start < EXTENT_MAP_LAST_BYTE) + if (em->block_start < EXTENT_MAP_LAST_BYTE && + !test_bit(EXTENT_FLAG_COMPRESSED, &em->flags)) { em->block_start += start_diff; + em->block_len -= start_diff; + } return add_extent_mapping(em_tree, em); } +static noinline int uncompress_inline(struct btrfs_path *path, + struct inode *inode, struct page *page, + size_t pg_offset, u64 extent_offset, + struct btrfs_file_extent_item *item) +{ + int ret; + struct extent_buffer *leaf = path->nodes[0]; + char *tmp; + size_t max_size; + unsigned long inline_size; + unsigned long ptr; + + WARN_ON(pg_offset != 0); + max_size = btrfs_file_extent_ram_bytes(leaf, item); + inline_size = btrfs_file_extent_inline_item_len(leaf, + btrfs_item_nr(leaf, path->slots[0])); + tmp = kmalloc(inline_size, GFP_NOFS); + ptr = btrfs_file_extent_inline_start(item); + + read_extent_buffer(leaf, tmp, ptr, inline_size); + + max_size = min(PAGE_CACHE_SIZE, max_size); + ret = btrfs_zlib_decompress(tmp, page, extent_offset, + inline_size, max_size); + if (ret) { + char *kaddr = kmap_atomic(page, KM_USER0); + unsigned long copy_size = min_t(u64, + PAGE_CACHE_SIZE - pg_offset, + max_size - extent_offset); + memset(kaddr + pg_offset, 0, copy_size); + kunmap_atomic(kaddr, KM_USER0); + } + kfree(tmp); + return 0; +} + /* * a bit scary, this does extent mapping from logical file offset to the disk. * the ugly parts come from merging extents from the disk with the @@ -2927,6 +3393,7 @@ struct extent_map *btrfs_get_extent(struct inode *inode, struct page *page, struct extent_map_tree *em_tree = &BTRFS_I(inode)->extent_tree; struct extent_io_tree *io_tree = &BTRFS_I(inode)->io_tree; struct btrfs_trans_handle *trans = NULL; + int compressed; again: spin_lock(&em_tree->lock); @@ -2951,6 +3418,7 @@ again: em->bdev = root->fs_info->fs_devices->latest_bdev; em->start = EXTENT_MAP_HOLE; em->len = (u64)-1; + em->block_len = (u64)-1; if (!path) { path = btrfs_alloc_path(); @@ -2983,6 +3451,7 @@ again: found_type = btrfs_file_extent_type(leaf, item); extent_start = found_key.offset; + compressed = btrfs_file_extent_compression(leaf, item); if (found_type == BTRFS_FILE_EXTENT_REG) { extent_end = extent_start + btrfs_file_extent_num_bytes(leaf, item); @@ -3005,10 +3474,18 @@ again: em->block_start = EXTENT_MAP_HOLE; goto insert; } - bytenr += btrfs_file_extent_offset(leaf, item); - em->block_start = bytenr; em->start = extent_start; em->len = extent_end - extent_start; + if (compressed) { + set_bit(EXTENT_FLAG_COMPRESSED, &em->flags); + em->block_start = bytenr; + em->block_len = btrfs_file_extent_disk_num_bytes(leaf, + item); + } else { + bytenr += btrfs_file_extent_offset(leaf, item); + em->block_start = bytenr; + em->block_len = em->len; + } goto insert; } else if (found_type == BTRFS_FILE_EXTENT_INLINE) { u64 page_start; @@ -3018,8 +3495,7 @@ again: size_t extent_offset; size_t copy_size; - size = btrfs_file_extent_inline_len(leaf, btrfs_item_nr(leaf, - path->slots[0])); + size = btrfs_file_extent_inline_len(leaf, item); extent_end = (extent_start + size + root->sectorsize - 1) & ~((u64)root->sectorsize - 1); if (start < extent_start || start >= extent_end) { @@ -3035,9 +3511,10 @@ again: } em->block_start = EXTENT_MAP_INLINE; - if (!page) { + if (!page || create) { em->start = extent_start; - em->len = size; + em->len = (size + root->sectorsize - 1) & + ~((u64)root->sectorsize - 1); goto out; } @@ -3048,11 +3525,22 @@ again: em->start = extent_start + extent_offset; em->len = (copy_size + root->sectorsize - 1) & ~((u64)root->sectorsize - 1); - map = kmap(page); + if (compressed) + set_bit(EXTENT_FLAG_COMPRESSED, &em->flags); ptr = btrfs_file_extent_inline_start(item) + extent_offset; if (create == 0 && !PageUptodate(page)) { - read_extent_buffer(leaf, map + pg_offset, ptr, - copy_size); + if (btrfs_file_extent_compression(leaf, item) == + BTRFS_COMPRESS_ZLIB) { + ret = uncompress_inline(path, inode, page, + pg_offset, + extent_offset, item); + BUG_ON(ret); + } else { + map = kmap(page); + read_extent_buffer(leaf, map + pg_offset, ptr, + copy_size); + kunmap(page); + } flush_dcache_page(page); } else if (create && PageUptodate(page)) { if (!trans) { @@ -3063,11 +3551,12 @@ again: trans = btrfs_join_transaction(root, 1); goto again; } + map = kmap(page); write_extent_buffer(leaf, map + pg_offset, ptr, copy_size); + kunmap(page); btrfs_mark_buffer_dirty(leaf); } - kunmap(page); set_extent_uptodate(io_tree, em->start, extent_map_end(em) - 1, GFP_NOFS); goto insert; @@ -3779,6 +4268,11 @@ static int btrfs_symlink(struct inode *dir, struct dentry *dentry, btrfs_set_file_extent_generation(leaf, ei, trans->transid); btrfs_set_file_extent_type(leaf, ei, BTRFS_FILE_EXTENT_INLINE); + btrfs_set_file_extent_encryption(leaf, ei, 0); + btrfs_set_file_extent_compression(leaf, ei, 0); + btrfs_set_file_extent_other_encoding(leaf, ei, 0); + btrfs_set_file_extent_ram_bytes(leaf, ei, name_len); + ptr = btrfs_file_extent_inline_start(ei); write_extent_buffer(leaf, symname, ptr, name_len); btrfs_mark_buffer_dirty(leaf); |