diff options
Diffstat (limited to 'fs/ext3/inode.c')
| -rw-r--r-- | fs/ext3/inode.c | 105 |
1 files changed, 76 insertions, 29 deletions
diff --git a/fs/ext3/inode.c b/fs/ext3/inode.c index 76e22c9..fcfb10f 100644 --- a/fs/ext3/inode.c +++ b/fs/ext3/inode.c @@ -330,7 +330,7 @@ static int ext3_block_to_path(struct inode *inode, ext3_warning (inode->i_sb, "ext3_block_to_path", "block > big"); } if (boundary) - *boundary = (i_block & (ptrs - 1)) == (final - 1); + *boundary = final - 1 - (i_block & (ptrs - 1)); return n; } @@ -669,11 +669,15 @@ err_out: * akpm: `handle' can be NULL if create == 0. * * The BKL may not be held on entry here. Be sure to take it early. + * return > 0, # of blocks mapped or allocated. + * return = 0, if plain lookup failed. + * return < 0, error case. */ int -ext3_get_block_handle(handle_t *handle, struct inode *inode, sector_t iblock, - struct buffer_head *bh_result, int create, int extend_disksize) +ext3_get_blocks_handle(handle_t *handle, struct inode *inode, sector_t iblock, + unsigned long maxblocks, struct buffer_head *bh_result, + int create, int extend_disksize) { int err = -EIO; int offsets[4]; @@ -681,11 +685,15 @@ ext3_get_block_handle(handle_t *handle, struct inode *inode, sector_t iblock, Indirect *partial; unsigned long goal; int left; - int boundary = 0; - const int depth = ext3_block_to_path(inode, iblock, offsets, &boundary); + int blocks_to_boundary = 0; + int depth; struct ext3_inode_info *ei = EXT3_I(inode); + int count = 0; + unsigned long first_block = 0; + J_ASSERT(handle != NULL || create == 0); + depth = ext3_block_to_path(inode, iblock, offsets, &blocks_to_boundary); if (depth == 0) goto out; @@ -694,8 +702,31 @@ ext3_get_block_handle(handle_t *handle, struct inode *inode, sector_t iblock, /* Simplest case - block found, no allocation needed */ if (!partial) { + first_block = chain[depth - 1].key; clear_buffer_new(bh_result); - goto got_it; + count++; + /*map more blocks*/ + while (count < maxblocks && count <= blocks_to_boundary) { + if (!verify_chain(chain, partial)) { + /* + * Indirect block might be removed by + * truncate while we were reading it. + * Handling of that case: forget what we've + * got now. Flag the err as EAGAIN, so it + * will reread. + */ + err = -EAGAIN; + count = 0; + break; + } + if (le32_to_cpu(*(chain[depth-1].p+count) == + (first_block + count))) + count++; + else + break; + } + if (err != -EAGAIN) + goto got_it; } /* Next simple case - plain lookup or failed read of indirect block */ @@ -723,6 +754,7 @@ ext3_get_block_handle(handle_t *handle, struct inode *inode, sector_t iblock, } partial = ext3_get_branch(inode, depth, offsets, chain, &err); if (!partial) { + count++; mutex_unlock(&ei->truncate_mutex); if (err) goto cleanup; @@ -772,8 +804,9 @@ ext3_get_block_handle(handle_t *handle, struct inode *inode, sector_t iblock, set_buffer_new(bh_result); got_it: map_bh(bh_result, inode->i_sb, le32_to_cpu(chain[depth-1].key)); - if (boundary) + if (blocks_to_boundary == 0) set_buffer_boundary(bh_result); + err = count; /* Clean up and exit */ partial = chain + depth - 1; /* the whole chain */ cleanup: @@ -787,21 +820,6 @@ out: return err; } -static int ext3_get_block(struct inode *inode, sector_t iblock, - struct buffer_head *bh_result, int create) -{ - handle_t *handle = NULL; - int ret; - - if (create) { - handle = ext3_journal_current_handle(); - J_ASSERT(handle != 0); - } - ret = ext3_get_block_handle(handle, inode, iblock, - bh_result, create, 1); - return ret; -} - #define DIO_CREDITS (EXT3_RESERVE_TRANS_BLOCKS + 32) static int @@ -812,9 +830,12 @@ ext3_direct_io_get_blocks(struct inode *inode, sector_t iblock, handle_t *handle = journal_current_handle(); int ret = 0; - if (!handle) + if (!create) goto get_block; /* A read */ + if (max_blocks == 1) + goto get_block; /* A single block get */ + if (handle->h_transaction->t_state == T_LOCKED) { /* * Huge direct-io writes can hold off commits for long @@ -841,13 +862,31 @@ ext3_direct_io_get_blocks(struct inode *inode, sector_t iblock, } get_block: - if (ret == 0) - ret = ext3_get_block_handle(handle, inode, iblock, - bh_result, create, 0); - bh_result->b_size = (1 << inode->i_blkbits); + if (ret == 0) { + ret = ext3_get_blocks_handle(handle, inode, iblock, + max_blocks, bh_result, create, 0); + if (ret > 0) { + bh_result->b_size = (ret << inode->i_blkbits); + ret = 0; + } + } return ret; } +static int ext3_get_blocks(struct inode *inode, sector_t iblock, + unsigned long maxblocks, struct buffer_head *bh_result, + int create) +{ + return ext3_direct_io_get_blocks(inode, iblock, maxblocks, + bh_result, create); +} + +static int ext3_get_block(struct inode *inode, sector_t iblock, + struct buffer_head *bh_result, int create) +{ + return ext3_get_blocks(inode, iblock, 1, bh_result, create); +} + /* * `handle' can be NULL if create is zero */ @@ -862,8 +901,16 @@ struct buffer_head *ext3_getblk(handle_t *handle, struct inode * inode, dummy.b_state = 0; dummy.b_blocknr = -1000; buffer_trace_init(&dummy.b_history); - *errp = ext3_get_block_handle(handle, inode, block, &dummy, create, 1); - if (!*errp && buffer_mapped(&dummy)) { + err = ext3_get_blocks_handle(handle, inode, block, 1, + &dummy, create, 1); + if (err == 1) { + err = 0; + } else if (err >= 0) { + WARN_ON(1); + err = -EIO; + } + *errp = err; + if (!err && buffer_mapped(&dummy)) { struct buffer_head *bh; bh = sb_getblk(inode->i_sb, dummy.b_blocknr); if (!bh) { |
