diff options
Diffstat (limited to 'fs/ext4/inode.c')
| -rw-r--r-- | fs/ext4/inode.c | 593 |
1 files changed, 365 insertions, 228 deletions
diff --git a/fs/ext4/inode.c b/fs/ext4/inode.c index 2a9ffd5..875db94 100644 --- a/fs/ext4/inode.c +++ b/fs/ext4/inode.c @@ -372,20 +372,21 @@ static int ext4_block_to_path(struct inode *inode, } static int __ext4_check_blockref(const char *function, struct inode *inode, - __le32 *p, unsigned int max) { - - unsigned int maxblocks = ext4_blocks_count(EXT4_SB(inode->i_sb)->s_es); + __le32 *p, unsigned int max) +{ __le32 *bref = p; + unsigned int blk; + while (bref < p+max) { - if (unlikely(le32_to_cpu(*bref) >= maxblocks)) { + blk = le32_to_cpu(*bref++); + if (blk && + unlikely(!ext4_data_block_valid(EXT4_SB(inode->i_sb), + blk, 1))) { ext4_error(inode->i_sb, function, - "block reference %u >= max (%u) " - "in inode #%lu, offset=%d", - le32_to_cpu(*bref), maxblocks, - inode->i_ino, (int)(bref-p)); + "invalid block reference %u " + "in inode #%lu", blk, inode->i_ino); return -EIO; } - bref++; } return 0; } @@ -892,6 +893,10 @@ err_out: } /* + * The ext4_ind_get_blocks() function handles non-extents inodes + * (i.e., using the traditional indirect/double-indirect i_blocks + * scheme) for ext4_get_blocks(). + * * Allocation strategy is simple: if we have to allocate something, we will * have to go the whole way to leaf. So let's do it before attaching anything * to tree, set linkage between the newborn blocks, write them if sync is @@ -909,15 +914,16 @@ err_out: * return = 0, if plain lookup failed. * return < 0, error case. * - * - * Need to be called with - * down_read(&EXT4_I(inode)->i_data_sem) if not allocating file system block - * (ie, create is zero). Otherwise down_write(&EXT4_I(inode)->i_data_sem) + * The ext4_ind_get_blocks() function should be called with + * down_write(&EXT4_I(inode)->i_data_sem) if allocating filesystem + * blocks (i.e., flags has EXT4_GET_BLOCKS_CREATE set) or + * down_read(&EXT4_I(inode)->i_data_sem) if not allocating file system + * blocks. */ -static int ext4_get_blocks_handle(handle_t *handle, struct inode *inode, +static int ext4_ind_get_blocks(handle_t *handle, struct inode *inode, ext4_lblk_t iblock, unsigned int maxblocks, struct buffer_head *bh_result, - int create, int extend_disksize) + int flags) { int err = -EIO; ext4_lblk_t offsets[4]; @@ -927,14 +933,11 @@ static int ext4_get_blocks_handle(handle_t *handle, struct inode *inode, int indirect_blks; int blocks_to_boundary = 0; int depth; - struct ext4_inode_info *ei = EXT4_I(inode); int count = 0; ext4_fsblk_t first_block = 0; - loff_t disksize; - J_ASSERT(!(EXT4_I(inode)->i_flags & EXT4_EXTENTS_FL)); - J_ASSERT(handle != NULL || create == 0); + J_ASSERT(handle != NULL || (flags & EXT4_GET_BLOCKS_CREATE) == 0); depth = ext4_block_to_path(inode, iblock, offsets, &blocks_to_boundary); @@ -963,7 +966,7 @@ static int ext4_get_blocks_handle(handle_t *handle, struct inode *inode, } /* Next simple case - plain lookup or failed read of indirect block */ - if (!create || err == -EIO) + if ((flags & EXT4_GET_BLOCKS_CREATE) == 0 || err == -EIO) goto cleanup; /* @@ -997,19 +1000,7 @@ static int ext4_get_blocks_handle(handle_t *handle, struct inode *inode, if (!err) err = ext4_splice_branch(handle, inode, iblock, partial, indirect_blks, count); - /* - * i_disksize growing is protected by i_data_sem. Don't forget to - * protect it if you're about to implement concurrent - * ext4_get_block() -bzzz - */ - if (!err && extend_disksize) { - disksize = ((loff_t) iblock + count) << inode->i_blkbits; - if (disksize > i_size_read(inode)) - disksize = i_size_read(inode); - if (disksize > ei->i_disksize) - ei->i_disksize = disksize; - } - if (err) + else goto cleanup; set_buffer_new(bh_result); @@ -1120,8 +1111,23 @@ static void ext4_da_update_reserve_space(struct inode *inode, int used) ext4_discard_preallocations(inode); } +static int check_block_validity(struct inode *inode, sector_t logical, + sector_t phys, int len) +{ + if (!ext4_data_block_valid(EXT4_SB(inode->i_sb), phys, len)) { + ext4_error(inode->i_sb, "check_block_validity", + "inode #%lu logical block %llu mapped to %llu " + "(size %d)", inode->i_ino, + (unsigned long long) logical, + (unsigned long long) phys, len); + WARN_ON(1); + return -EIO; + } + return 0; +} + /* - * The ext4_get_blocks_wrap() function try to look up the requested blocks, + * The ext4_get_blocks() function tries to look up the requested blocks, * and returns if the blocks are already mapped. * * Otherwise it takes the write lock of the i_data_sem and allocate blocks @@ -1129,7 +1135,7 @@ static void ext4_da_update_reserve_space(struct inode *inode, int used) * mapped. * * If file type is extents based, it will call ext4_ext_get_blocks(), - * Otherwise, call with ext4_get_blocks_handle() to handle indirect mapping + * Otherwise, call with ext4_ind_get_blocks() to handle indirect mapping * based files * * On success, it returns the number of blocks being mapped or allocate. @@ -1142,9 +1148,9 @@ static void ext4_da_update_reserve_space(struct inode *inode, int used) * * It returns the error in case of allocation failure. */ -int ext4_get_blocks_wrap(handle_t *handle, struct inode *inode, sector_t block, - unsigned int max_blocks, struct buffer_head *bh, - int create, int extend_disksize, int flag) +int ext4_get_blocks(handle_t *handle, struct inode *inode, sector_t block, + unsigned int max_blocks, struct buffer_head *bh, + int flags) { int retval; @@ -1152,21 +1158,28 @@ int ext4_get_blocks_wrap(handle_t *handle, struct inode *inode, sector_t block, clear_buffer_unwritten(bh); /* - * Try to see if we can get the block without requesting - * for new file system block. + * Try to see if we can get the block without requesting a new + * file system block. */ down_read((&EXT4_I(inode)->i_data_sem)); if (EXT4_I(inode)->i_flags & EXT4_EXTENTS_FL) { retval = ext4_ext_get_blocks(handle, inode, block, max_blocks, - bh, 0, 0); + bh, 0); } else { - retval = ext4_get_blocks_handle(handle, - inode, block, max_blocks, bh, 0, 0); + retval = ext4_ind_get_blocks(handle, inode, block, max_blocks, + bh, 0); } up_read((&EXT4_I(inode)->i_data_sem)); + if (retval > 0 && buffer_mapped(bh)) { + int ret = check_block_validity(inode, block, + bh->b_blocknr, retval); + if (ret != 0) + return ret; + } + /* If it is only a block(s) look up */ - if (!create) + if ((flags & EXT4_GET_BLOCKS_CREATE) == 0) return retval; /* @@ -1205,7 +1218,7 @@ int ext4_get_blocks_wrap(handle_t *handle, struct inode *inode, sector_t block, * let the underlying get_block() function know to * avoid double accounting */ - if (flag) + if (flags & EXT4_GET_BLOCKS_DELALLOC_RESERVE) EXT4_I(inode)->i_delalloc_reserved_flag = 1; /* * We need to check for EXT4 here because migrate @@ -1213,10 +1226,10 @@ int ext4_get_blocks_wrap(handle_t *handle, struct inode *inode, sector_t block, */ if (EXT4_I(inode)->i_flags & EXT4_EXTENTS_FL) { retval = ext4_ext_get_blocks(handle, inode, block, max_blocks, - bh, create, extend_disksize); + bh, flags); } else { - retval = ext4_get_blocks_handle(handle, inode, block, - max_blocks, bh, create, extend_disksize); + retval = ext4_ind_get_blocks(handle, inode, block, + max_blocks, bh, flags); if (retval > 0 && buffer_new(bh)) { /* @@ -1229,18 +1242,23 @@ int ext4_get_blocks_wrap(handle_t *handle, struct inode *inode, sector_t block, } } - if (flag) { + if (flags & EXT4_GET_BLOCKS_DELALLOC_RESERVE) EXT4_I(inode)->i_delalloc_reserved_flag = 0; - /* - * Update reserved blocks/metadata blocks - * after successful block allocation - * which were deferred till now - */ - if ((retval > 0) && buffer_delay(bh)) - ext4_da_update_reserve_space(inode, retval); - } + + /* + * Update reserved blocks/metadata blocks after successful + * block allocation which had been deferred till now. + */ + if ((retval > 0) && (flags & EXT4_GET_BLOCKS_UPDATE_RESERVE_SPACE)) + ext4_da_update_reserve_space(inode, retval); up_write((&EXT4_I(inode)->i_data_sem)); + if (retval > 0 && buffer_mapped(bh)) { + int ret = check_block_validity(inode, block, + bh->b_blocknr, retval); + if (ret != 0) + return ret; + } return retval; } @@ -1268,8 +1286,8 @@ int ext4_get_block(struct inode *inode, sector_t iblock, started = 1; } - ret = ext4_get_blocks_wrap(handle, inode, iblock, - max_blocks, bh_result, create, 0, 0); + ret = ext4_get_blocks(handle, inode, iblock, max_blocks, bh_result, + create ? EXT4_GET_BLOCKS_CREATE : 0); if (ret > 0) { bh_result->b_size = (ret << inode->i_blkbits); ret = 0; @@ -1288,17 +1306,19 @@ struct buffer_head *ext4_getblk(handle_t *handle, struct inode *inode, { struct buffer_head dummy; int fatal = 0, err; + int flags = 0; J_ASSERT(handle != NULL || create == 0); dummy.b_state = 0; dummy.b_blocknr = -1000; buffer_trace_init(&dummy.b_history); - err = ext4_get_blocks_wrap(handle, inode, block, 1, - &dummy, create, 1, 0); + if (create) + flags |= EXT4_GET_BLOCKS_CREATE; + err = ext4_get_blocks(handle, inode, block, 1, &dummy, flags); /* - * ext4_get_blocks_handle() returns number of blocks - * mapped. 0 in case of a HOLE. + * ext4_get_blocks() returns number of blocks mapped. 0 in + * case of a HOLE. */ if (err > 0) { if (err > 1) @@ -1439,7 +1459,7 @@ static int ext4_write_begin(struct file *file, struct address_space *mapping, struct page **pagep, void **fsdata) { struct inode *inode = mapping->host; - int ret, needed_blocks = ext4_writepage_trans_blocks(inode); + int ret, needed_blocks; handle_t *handle; int retries = 0; struct page *page; @@ -1450,6 +1470,11 @@ static int ext4_write_begin(struct file *file, struct address_space *mapping, "dev %s ino %lu pos %llu len %u flags %u", inode->i_sb->s_id, inode->i_ino, (unsigned long long) pos, len, flags); + /* + * Reserve one block more for addition to orphan list in case + * we allocate blocks but write fails for some reason + */ + needed_blocks = ext4_writepage_trans_blocks(inode) + 1; index = pos >> PAGE_CACHE_SHIFT; from = pos & (PAGE_CACHE_SIZE - 1); to = from + len; @@ -1483,15 +1508,30 @@ retry: if (ret) { unlock_page(page); - ext4_journal_stop(handle); page_cache_release(page); /* * block_write_begin may have instantiated a few blocks * outside i_size. Trim these off again. Don't need * i_size_read because we hold i_mutex. + * + * Add inode to orphan list in case we crash before + * truncate finishes */ if (pos + len > inode->i_size) + ext4_orphan_add(handle, inode); + + ext4_journal_stop(handle); + if (pos + len > inode->i_size) { vmtruncate(inode, inode->i_size); + /* + * If vmtruncate failed early the inode might + * still be on the orphan list; we need to + * make sure the inode is removed from the + * orphan list in that case. + */ + if (inode->i_nlink) + ext4_orphan_del(NULL, inode); + } } if (ret == -ENOSPC && ext4_should_retry_alloc(inode->i_sb, &retries)) @@ -1509,6 +1549,52 @@ static int write_end_fn(handle_t *handle, struct buffer_head *bh) return ext4_handle_dirty_metadata(handle, NULL, bh); } +static int ext4_generic_write_end(struct file *file, + struct address_space *mapping, + loff_t pos, unsigned len, unsigned copied, + struct page *page, void *fsdata) +{ + int i_size_changed = 0; + struct inode *inode = mapping->host; + handle_t *handle = ext4_journal_current_handle(); + + copied = block_write_end(file, mapping, pos, len, copied, page, fsdata); + + /* + * No need to use i_size_read() here, the i_size + * cannot change under us because we hold i_mutex. + * + * But it's important to update i_size while still holding page lock: + * page writeout could otherwise come in and zero beyond i_size. + */ + if (pos + copied > inode->i_size) { + i_size_write(inode, pos + copied); + i_size_changed = 1; + } + + if (pos + copied > EXT4_I(inode)->i_disksize) { + /* We need to mark inode dirty even if + * new_i_size is less that inode->i_size + * bu greater than i_disksize.(hint delalloc) + */ + ext4_update_i_disksize(inode, (pos + copied)); + i_size_changed = 1; + } + unlock_page(page); + page_cache_release(page); + + /* + * Don't mark the inode dirty under page lock. First, it unnecessarily + * makes the holding time of page lock longer. Second, it forces lock + * ordering of page lock and transaction start for journaling + * filesystems. + */ + if (i_size_changed) + ext4_mark_inode_dirty(handle, inode); + + return copied; +} + /* * We need to pick up the new inode size which generic_commit_write gave us * `file' can be NULL - eg, when called from page_symlink(). @@ -1532,21 +1618,15 @@ static int ext4_ordered_write_end(struct file *file, ret = ext4_jbd2_file_inode(handle, inode); if (ret == 0) { - loff_t new_i_size; - - new_i_size = pos + copied; - if (new_i_size > EXT4_I(inode)->i_disksize) { - ext4_update_i_disksize(inode, new_i_size); - /* We need to mark inode dirty even if - * new_i_size is less that inode->i_size - * bu greater than i_disksize.(hint delalloc) - */ - ext4_mark_inode_dirty(handle, inode); - } - - ret2 = generic_write_end(file, mapping, pos, len, copied, + ret2 = ext4_generic_write_end(file, mapping, pos, len, copied, page, fsdata); copied = ret2; + if (pos + len > inode->i_size) + /* if we have allocated more blocks and copied + * less. We will have blocks allocated outside + * inode->i_size. So truncate them + */ + ext4_orphan_add(handle, inode); if (ret2 < 0) ret = ret2; } @@ -1554,6 +1634,18 @@ static int ext4_ordered_write_end(struct file *file, if (!ret) ret = ret2; + if (pos + len > inode->i_size) { + vmtruncate(inode, inode->i_size); + /* + * If vmtruncate failed early the inode might still be + * on the orphan list; we need to make sure the inode + * is removed from the orphan list in that case. + */ + if (inode->i_nlink) + ext4_orphan_del(NULL, inode); + } + + return ret ? ret : copied; } @@ -1565,25 +1657,21 @@ static int ext4_writeback_write_end(struct file *file, handle_t *handle = ext4_journal_current_handle(); struct inode *inode = mapping->host; int ret = 0, ret2; - loff_t new_i_size; trace_mark(ext4_writeback_write_end, "dev %s ino %lu pos %llu len %u copied %u", inode->i_sb->s_id, inode->i_ino, (unsigned long long) pos, len, copied); - new_i_size = pos + copied; - if (new_i_size > EXT4_I(inode)->i_disksize) { - ext4_update_i_disksize(inode, new_i_size); - /* We need to mark inode dirty even if - * new_i_size is less that inode->i_size - * bu greater than i_disksize.(hint delalloc) - */ - ext4_mark_inode_dirty(handle, inode); - } - - ret2 = generic_write_end(file, mapping, pos, len, copied, + ret2 = ext4_generic_write_end(file, mapping, pos, len, copied, page, fsdata); copied = ret2; + if (pos + len > inode->i_size) + /* if we have allocated more blocks and copied + * less. We will have blocks allocated outside + * inode->i_size. So truncate them + */ + ext4_orphan_add(handle, inode); + if (ret2 < 0) ret = ret2; @@ -1591,6 +1679,17 @@ static int ext4_writeback_write_end(struct file *file, if (!ret) ret = ret2; + if (pos + len > inode->i_size) { + vmtruncate(inode, inode->i_size); + /* + * If vmtruncate failed early the inode might still be + * on the orphan list; we need to make sure the inode + * is removed from the orphan list in that case. + */ + if (inode->i_nlink) + ext4_orphan_del(NULL, inode); + } + return ret ? ret : copied; } @@ -1635,10 +1734,27 @@ static int ext4_journalled_write_end(struct file *file, } unlock_page(page); + page_cache_release(page); + if (pos + len > inode->i_size) + /* if we have allocated more blocks and copied + * less. We will have blocks allocated outside + * inode->i_size. So truncate them + */ + ext4_orphan_add(handle, inode); + ret2 = ext4_journal_stop(handle); if (!ret) ret = ret2; - page_cache_release(page); + if (pos + len > inode->i_size) { + vmtruncate(inode, inode->i_size); + /* + * If vmtruncate failed early the inode might still be + * on the orphan list; we need to make sure the inode + * is removed from the orphan list in that case. + */ + if (inode->i_nlink) + ext4_orphan_del(NULL, inode); + } return ret ? ret : copied; } @@ -1852,7 +1968,7 @@ static int mpage_da_submit_io(struct mpage_da_data *mpd) * @logical - first logical block to start assignment with * * the function goes through all passed space and put actual disk - * block numbers into buffer heads, dropping BH_Delay + * block numbers into buffer heads, dropping BH_Delay and BH_Unwritten */ static void mpage_put_bnr_to_bhs(struct mpage_da_data *mpd, sector_t logical, struct buffer_head *exbh) @@ -1902,16 +2018,24 @@ static void mpage_put_bnr_to_bhs(struct mpage_da_data *mpd, sector_t logical, do { if (cur_logical >= logical + blocks) break; - if (buffer_delay(bh)) { - bh->b_blocknr = pblock; - clear_buffer_delay(bh); - bh->b_bdev = inode->i_sb->s_bdev; - } else if (buffer_unwritten(bh)) { - bh->b_blocknr = pblock; - clear_buffer_unwritten(bh); - set_buffer_mapped(bh); - set_buffer_new(bh); - bh->b_bdev = inode->i_sb->s_bdev; + + if (buffer_delay(bh) || + buffer_unwritten(bh)) { + + BUG_ON(bh->b_bdev != inode->i_sb->s_bdev); + + if (buffer_delay(bh)) { + clear_buffer_delay(bh); + bh->b_blocknr = pblock; + } else { + /* + * unwritten already should have + * blocknr assigned. Verify that + */ + clear_buffer_unwritten(bh); + BUG_ON(bh->b_blocknr != pblock); + } + } else if (buffer_mapped(bh)) BUG_ON(bh->b_blocknr != pblock); @@ -1990,51 +2114,6 @@ static void ext4_print_free_blocks(struct inode *inode) return; } -#define EXT4_DELALLOC_RSVED 1 -static int ext4_da_get_block_write(struct inode *inode, sector_t iblock, - struct buffer_head *bh_result, int create) -{ - int ret; - unsigned max_blocks = bh_result->b_size >> inode->i_blkbits; - loff_t disksize = EXT4_I(inode)->i_disksize; - handle_t *handle = NULL; - - handle = ext4_journal_current_handle(); - BUG_ON(!handle); - ret = ext4_get_blocks_wrap(handle, inode, iblock, max_blocks, - bh_result, create, 0, EXT4_DELALLOC_RSVED); - if (ret <= 0) - return ret; - - bh_result->b_size = (ret << inode->i_blkbits); - - if (ext4_should_order_data(inode)) { - int retval; - retval = ext4_jbd2_file_inode(handle, inode); - if (retval) - /* - * Failed to add inode for ordered mode. Don't - * update file size - */ - return retval; - } - - /* - * Update on-disk size along with block allocation we don't - * use 'extend_disksize' as size may change within already - * allocated block -bzzz - */ - disksize = ((loff_t) iblock + ret) << inode->i_blkbits; - if (disksize > i_size_read(inode)) - disksize = i_size_read(inode); - if (disksize > EXT4_I(inode)->i_disksize) { - ext4_update_i_disksize(inode, disksize); - ret = ext4_mark_inode_dirty(handle, inode); - return ret; - } - return 0; -} - /* * mpage_da_map_blocks - go through given space * @@ -2045,29 +2124,57 @@ static int ext4_da_get_block_write(struct inode *inode, sector_t iblock, */ static int mpage_da_map_blocks(struct mpage_da_data *mpd) { - int err = 0; + int err, blks, get_blocks_flags; struct buffer_head new; - sector_t next; + sector_t next = mpd->b_blocknr; + unsigned max_blocks = mpd->b_size >> mpd->inode->i_blkbits; + loff_t disksize = EXT4_I(mpd->inode)->i_disksize; + handle_t *handle = NULL; /* * We consider only non-mapped and non-allocated blocks */ if ((mpd->b_state & (1 << BH_Mapped)) && - !(mpd->b_state & (1 << BH_Delay))) + !(mpd->b_state & (1 << BH_Delay)) && + !(mpd->b_state & (1 << BH_Unwritten))) return 0; - new.b_state = mpd->b_state; - new.b_blocknr = 0; - new.b_size = mpd->b_size; - next = mpd->b_blocknr; + /* - * If we didn't accumulate anything - * to write simply return + * If we didn't accumulate anything to write simply return */ - if (!new.b_size) + if (!mpd->b_size) return 0; - err = ext4_da_get_block_write(mpd->inode, next, &new, 1); - if (err) { + handle = ext4_journal_current_handle(); + BUG_ON(!handle); + + /* + * Call ext4_get_blocks() to allocate any delayed allocation + * blocks, or to convert an uninitialized extent to be + * initialized (in the case where we have written into + * one or more preallocated blocks). + * + * We pass in the magic EXT4_GET_BLOCKS_DELALLOC_RESERVE to + * indicate that we are on the delayed allocation path. This + * affects functions in many different parts of the allocation + * call path. This flag exists primarily because we don't + * want to change *many* call functions, so ext4_get_blocks() + * will set the magic i_delalloc_reserved_flag once the + * inode's allocation semaphore is taken. + * + * If the blocks in questions were delalloc blocks, set + * EXT4_GET_BLOCKS_DELALLOC_RESERVE so the delalloc accounting + * variables are updated after the blocks have been allocated. + */ + new.b_state = 0; + get_blocks_flags = (EXT4_GET_BLOCKS_CREATE | + EXT4_GET_BLOCKS_DELALLOC_RESERVE); + if (mpd->b_state & (1 << BH_Delay)) + get_blocks_flags |= EXT4_GET_BLOCKS_UPDATE_RESERVE_SPACE; + blks = ext4_get_blocks(handle, mpd->inode, next, max_blocks, + &new, get_blocks_flags); + if (blks < 0) { + err = blks; /* * If get block returns with error we simply * return. Later writepage will redirty the page and @@ -2100,12 +2207,14 @@ static int mpage_da_map_blocks(struct mpage_da_data *mpd) if (err == -ENOSPC) { ext4_print_free_blocks(mpd->inode); } - /* invlaidate all the pages */ + /* invalidate all the pages */ ext4_da_block_invalidatepages(mpd, next, mpd->b_size >> mpd->inode->i_blkbits); return err; } - BUG_ON(new.b_size == 0); + BUG_ON(blks == 0); + + new.b_size = (blks << mpd->inode->i_blkbits); if (buffer_new(&new)) __unmap_underlying_blocks(mpd->inode, &new); @@ -2118,6 +2227,23 @@ static int mpage_da_map_blocks(struct mpage_da_data *mpd) (mpd->b_state & (1 << BH_Unwritten))) mpage_put_bnr_to_bhs(mpd, next, &new); + if (ext4_should_order_data(mpd->inode)) { + err = ext4_jbd2_file_inode(handle, mpd->inode); + if (err) + return err; + } + + /* + * Update on-disk size along with block allocation. + */ + disksize = ((loff_t) next + blks) << mpd->inode->i_blkbits; + if (disksize > i_size_read(mpd->inode)) + disksize = i_size_read(mpd->inode); + if (disksize > EXT4_I(mpd->inode)->i_disksize) { + ext4_update_i_disksize(mpd->inode, disksize); + return ext4_mark_inode_dirty(handle, mpd->inode); + } + return 0; } @@ -2192,6 +2318,17 @@ flush_it: return; } +static int ext4_bh_unmapped_or_delay(handle_t *handle, struct buffer_head *bh) +{ + /* + * unmapped buffer is possible for holes. + * delay buffer is possible with delayed allocation. + * We also need to consider unwritten buffer as unmapped. + */ + return (!buffer_mapped(bh) || buffer_delay(bh) || + buffer_unwritten(bh)) && buffer_dirty(bh); +} + /* * __mpage_da_writepage - finds extent of pages and blocks * @@ -2276,8 +2413,7 @@ static int __mpage_da_writepage(struct page *page, * Otherwise we won't make progress * with the page in ext4_da_writepage */ - if (buffer_dirty(bh) && - (!buffer_mapped(bh) || buffer_delay(bh))) { + if (ext4_bh_unmapped_or_delay(NULL, bh)) { mpage_add_bh_to_extent(mpd, logical, bh->b_size, bh->b_state); @@ -2303,8 +2439,16 @@ static int __mpage_da_writepage(struct page *page, } /* - * this is a special callback for ->write_begin() only - * it's intention is to return mapped block or reserve space + * This is a special get_blocks_t callback which is used by + * ext4_da_write_begin(). It will either return mapped block or + * reserve space for a single block. + * + * For delayed buffer_head we have BH_Mapped, BH_New, BH_Delay set. + * We also have b_blocknr = -1 and b_bdev initialized properly + * + * For unwritten buffer_head we have BH_Mapped, BH_New, BH_Unwritten set. + * We also have b_blocknr = physicalblock mapping unwritten extent and b_bdev + * initialized properly. */ static int ext4_da_get_block_prep(struct inode *inode, sector_t iblock, struct buffer_head *bh_result, int create) @@ -2323,7 +2467,7 @@ static int ext4_da_get_block_prep(struct inode *inode, sector_t iblock, * preallocated blocks are unmapped but should treated * the same as allocated blocks. */ - ret = ext4_get_blocks_wrap(NULL, inode, iblock, 1, bh_result, 0, 0, 0); + ret = ext4_get_blocks(NULL, inode, iblock, 1, bh_result, 0); if ((ret == 0) && !buffer_delay(bh_result)) { /* the block isn't (pre)allocated yet, let's reserve space */ /* @@ -2340,40 +2484,53 @@ static int ext4_da_get_block_prep(struct inode *inode, sector_t iblock, set_buffer_delay(bh_result); } else if (ret > 0) { bh_result->b_size = (ret << inode->i_blkbits); - /* - * With sub-block writes into unwritten extents - * we also need to mark the buffer as new so that - * the unwritten parts of the buffer gets correctly zeroed. - */ - if (buffer_unwritten(bh_result)) + if (buffer_unwritten(bh_result)) { + /* A delayed write to unwritten bh should + * be marked new and mapped. Mapped ensures + * that we don't do get_block multiple times + * when we write to the same offset and new + * ensures that we do proper zero out for + * partial write. + */ set_buffer_new(bh_result); + set_buffer_mapped(bh_result); + } ret = 0; } return ret; } -static int ext4_bh_unmapped_or_delay(handle_t *handle, struct buffer_head *bh) -{ - /* - * unmapped buffer is possible for holes. - * delay buffer is possible with delayed allocation - */ - return ((!buffer_mapped(bh) || buffer_delay(bh)) && buffer_dirty(bh)); -} - -static int ext4_normal_get_block_write(struct inode *inode, sector_t iblock, +/* + * This function is used as a standard get_block_t calback function + * when there is no desire to allocate any blocks. It is used as a + * callback function for block_prepare_write(), nobh_writepage(), and + * block_write_full_page(). These functions should only try to map a + * single block at a time. + * + * Since this function doesn't do block allocations even if the caller + * requests it by passing in create=1, it is critically important that + * any caller checks to make sure that any buffer heads are returned + * by this function are either all already mapped or marked for + * delayed allocation before calling nobh_writepage() or + * block_write_full_page(). Otherwise, b_blocknr could be left + * unitialized, and the page write functions will be taken by + * surprise. + */ +static int noalloc_get_block_write(struct inode *inode, sector_t iblock, struct buffer_head *bh_result, int create) { int ret = 0; unsigned max_blocks = bh_result->b_size >> inode->i_blkbits; + BUG_ON(bh_result->b_size != inode->i_sb->s_blocksize); + /* * we don't want to do block allocation in writepage * so call get_block_wrap with create = 0 */ - ret = ext4_get_blocks_wrap(NULL, inode, iblock, max_blocks, - bh_result, 0, 0, 0); + ret = ext4_get_blocks(NULL, inode, iblock, max_blocks, bh_result, 0); + BUG_ON(create && ret == 0); if (ret > 0) { bh_result->b_size = (ret << inode->i_blkbits); ret = 0; @@ -2382,10 +2539,11 @@ static int ext4_normal_get_block_write(struct inode *inode, sector_t iblock, } /* - * get called vi ext4_da_writepages after taking page lock (have journal handle) - * get called via journal_submit_inode_data_buffers (no journal handle) - * get called via shrink_page_list via pdflush (no journal handle) - * or grab_page_cache when doing write_begin (have journal handle) + * This function can get called via... + * - ext4_da_writepages after taking page lock (have journal handle) + * - journal_submit_inode_data_buffers (no journal handle) + * - shrink_page_list via pdflush (no journal handle) + * - grab_page_cache when doing write_begin (have journal handle) */ static int ext4_da_writepage(struct page *page, struct writeback_control *wbc) @@ -2436,7 +2594,7 @@ static int ext4_da_writepage(struct page *page, * do block allocation here. */ ret = block_prepare_write(page, 0, PAGE_CACHE_SIZE, - ext4_normal_get_block_write); + noalloc_get_block_write); if (!ret) { page_bufs = page_buffers(page); /* check whether all are mapped and non delay */ @@ -2461,11 +2619,10 @@ static int ext4_da_writepage(struct page *page, } if (test_opt(inode->i_sb, NOBH) && ext4_should_writeback_data(inode)) - ret = nobh_writepage(page, ext4_normal_get_block_write, wbc); + ret = nobh_writepage(page, noalloc_get_block_write, wbc); else - ret = block_write_full_page(page, - ext4_normal_get_block_write, - wbc); + ret = block_write_full_page(page, noalloc_get_block_write, + wbc); return ret; } @@ -2777,7 +2934,7 @@ retry: *pagep = page; ret = block_write_begin(file, mapping, pos, len, flags, pagep, fsdata, - ext4_da_get_block_prep); + ext4_da_get_block_prep); if (ret < 0) { unlock_page(page); ext4_journal_stop(handle); @@ -2815,7 +2972,7 @@ static int ext4_da_should_update_i_disksize(struct page *page, for (i = 0; i < idx; i++) bh = bh->b_this_page; - if (!buffer_mapped(bh) || (buffer_delay(bh))) + if (!buffer_mapped(bh) || (buffer_delay(bh)) || buffer_unwritten(bh)) return 0; return 1; } @@ -3085,12 +3242,10 @@ static int __ext4_normal_writepage(struct page *page, struct inode *inode = page->mapping->host; if (test_opt(inode->i_sb, NOBH)) - return nobh_writepage(page, - ext4_normal_get_block_write, wbc); + return nobh_writepage(page, noalloc_get_block_write, wbc); else - return block_write_full_page(page, - ext4_normal_get_block_write, - wbc); + return block_write_full_page(page, noalloc_get_block_write, + wbc); } static int ext4_normal_writepage(struct page *page, @@ -3142,7 +3297,7 @@ static int __ext4_journalled_writepage(struct page *page, int err; ret = block_prepare_write(page, 0, PAGE_CACHE_SIZE, - ext4_normal_get_block_write); + noalloc_get_block_write); if (ret != 0) goto out_unlock; @@ -3227,9 +3382,8 @@ static int ext4_journalled_writepage(struct page *page, * really know unless we go poke around in the buffer_heads. * But block_write_full_page will do the right thing. */ - return block_write_full_page(page, - ext4_normal_get_block_write, - wbc); + return block_write_full_page(page, noalloc_get_block_write, + wbc); } no_write: redirty_page_for_writepage(wbc, page); @@ -3973,7 +4127,8 @@ void ext4_truncate(struct inode *inode) if (!ext4_can_truncate(inode)) return; - if (inode->i_size == 0 && !test_opt(inode->i_sb, NO_AUTO_DA_ALLOC)) + if (ei->i_disksize && inode->i_size == 0 && + !test_opt(inode->i_sb, NO_AUTO_DA_ALLOC)) ei->i_state |= EXT4_STATE_DA_ALLOC_CLOSE; if (EXT4_I(inode)->i_flags & EXT4_EXTENTS_FL) { @@ -4715,25 +4870,6 @@ int ext4_write_inode(struct inode *inode, int wait) return ext4_force_commit(inode->i_sb); } -int __ext4_write_dirty_metadata(struct inode *inode, struct buffer_head *bh) -{ - int err = 0; - - mark_buffer_dirty(bh); - if (inode && inode_needs_sync(inode)) { - sync_dirty_buffer(bh); - if (buffer_req(bh) && !buffer_uptodate(bh)) { - ext4_error(inode->i_sb, __func__, - "IO error syncing inode, " - "inode=%lu, block=%llu", - inode->i_ino, - (unsigned long long)bh->b_blocknr); - err = -EIO; - } - } - return err; -} - /* * ext4_setattr() * @@ -4930,7 +5066,8 @@ static int ext4_index_trans_blocks(struct inode *inode, int nrblocks, int chunk) */ int ext4_meta_trans_blocks(struct inode *inode, int nrblocks, int chunk) { - int groups, gdpblocks; + ext4_group_t groups, ngroups = ext4_get_groups_count(inode->i_sb); + int gdpblocks; int idxblocks; int ret = 0; @@ -4957,8 +5094,8 @@ int ext4_meta_trans_blocks(struct inode *inode, int nrblocks, int chunk) groups += nrblocks; gdpblocks = groups; - if (groups > EXT4_SB(inode->i_sb)->s_groups_count) - groups = EXT4_SB(inode->i_sb)->s_groups_count; + if (groups > ngroups) + groups = ngroups; if (groups > EXT4_SB(inode->i_sb)->s_gdb_count) gdpblocks = EXT4_SB(inode->i_sb)->s_gdb_count; @@ -4998,7 +5135,7 @@ int ext4_writepage_trans_blocks(struct inode *inode) * Calculate the journal credits for a chunk of data modification. * * This is called from DIO, fallocate or whoever calling - * ext4_get_blocks_wrap() to map/allocate a chunk of contigous disk blocks. + * ext4_get_blocks() to map/allocate a chunk of contigous disk blocks. * * journal buffers for data blocks are not included here, as DIO * and fallocate do no need to journal data buffers. |