From d635711daa98be86d4c7fd01499c34f566b54ccb Mon Sep 17 00:00:00 2001 From: =?UTF-8?q?Andr=C3=A9=20Fabian=20Silva=20Delgado?= Date: Fri, 10 Jun 2016 05:30:17 -0300 Subject: Linux-libre 4.6.2-gnu --- fs/ext4/extents.c | 128 +++++++++++++++++++++++++++--------------------------- 1 file changed, 63 insertions(+), 65 deletions(-) (limited to 'fs/ext4/extents.c') diff --git a/fs/ext4/extents.c b/fs/ext4/extents.c index 3753ceb0b..95bf4679a 100644 --- a/fs/ext4/extents.c +++ b/fs/ext4/extents.c @@ -15,7 +15,7 @@ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the * GNU General Public License for more details. * - * You should have received a copy of the GNU General Public Licens + * You should have received a copy of the GNU General Public License * along with this program; if not, write to the Free Software * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111- */ @@ -1736,6 +1736,12 @@ ext4_can_extents_be_merged(struct inode *inode, struct ext4_extent *ex1, */ if (ext1_ee_len + ext2_ee_len > EXT_INIT_MAX_LEN) return 0; + /* + * The check for IO to unwritten extent is somewhat racy as we + * increment i_unwritten / set EXT4_STATE_DIO_UNWRITTEN only after + * dropping i_data_sem. But reserved blocks should save us in that + * case. + */ if (ext4_ext_is_unwritten(ex1) && (ext4_test_inode_state(inode, EXT4_STATE_DIO_UNWRITTEN) || atomic_read(&EXT4_I(inode)->i_unwritten) || @@ -2293,59 +2299,69 @@ static int ext4_fill_fiemap_extents(struct inode *inode, } /* - * ext4_ext_put_gap_in_cache: - * calculate boundaries of the gap that the requested block fits into - * and cache this gap + * ext4_ext_determine_hole - determine hole around given block + * @inode: inode we lookup in + * @path: path in extent tree to @lblk + * @lblk: pointer to logical block around which we want to determine hole + * + * Determine hole length (and start if easily possible) around given logical + * block. We don't try too hard to find the beginning of the hole but @path + * actually points to extent before @lblk, we provide it. + * + * The function returns the length of a hole starting at @lblk. We update @lblk + * to the beginning of the hole if we managed to find it. */ -static void -ext4_ext_put_gap_in_cache(struct inode *inode, struct ext4_ext_path *path, - ext4_lblk_t block) +static ext4_lblk_t ext4_ext_determine_hole(struct inode *inode, + struct ext4_ext_path *path, + ext4_lblk_t *lblk) { int depth = ext_depth(inode); - ext4_lblk_t len; - ext4_lblk_t lblock; struct ext4_extent *ex; - struct extent_status es; + ext4_lblk_t len; ex = path[depth].p_ext; if (ex == NULL) { /* there is no extent yet, so gap is [0;-] */ - lblock = 0; + *lblk = 0; len = EXT_MAX_BLOCKS; - ext_debug("cache gap(whole file):"); - } else if (block < le32_to_cpu(ex->ee_block)) { - lblock = block; - len = le32_to_cpu(ex->ee_block) - block; - ext_debug("cache gap(before): %u [%u:%u]", - block, - le32_to_cpu(ex->ee_block), - ext4_ext_get_actual_len(ex)); - } else if (block >= le32_to_cpu(ex->ee_block) + } else if (*lblk < le32_to_cpu(ex->ee_block)) { + len = le32_to_cpu(ex->ee_block) - *lblk; + } else if (*lblk >= le32_to_cpu(ex->ee_block) + ext4_ext_get_actual_len(ex)) { ext4_lblk_t next; - lblock = le32_to_cpu(ex->ee_block) - + ext4_ext_get_actual_len(ex); + *lblk = le32_to_cpu(ex->ee_block) + ext4_ext_get_actual_len(ex); next = ext4_ext_next_allocated_block(path); - ext_debug("cache gap(after): [%u:%u] %u", - le32_to_cpu(ex->ee_block), - ext4_ext_get_actual_len(ex), - block); - BUG_ON(next == lblock); - len = next - lblock; + BUG_ON(next == *lblk); + len = next - *lblk; } else { BUG(); } + return len; +} - ext4_es_find_delayed_extent_range(inode, lblock, lblock + len - 1, &es); +/* + * ext4_ext_put_gap_in_cache: + * calculate boundaries of the gap that the requested block fits into + * and cache this gap + */ +static void +ext4_ext_put_gap_in_cache(struct inode *inode, ext4_lblk_t hole_start, + ext4_lblk_t hole_len) +{ + struct extent_status es; + + ext4_es_find_delayed_extent_range(inode, hole_start, + hole_start + hole_len - 1, &es); if (es.es_len) { /* There's delayed extent containing lblock? */ - if (es.es_lblk <= lblock) + if (es.es_lblk <= hole_start) return; - len = min(es.es_lblk - lblock, len); + hole_len = min(es.es_lblk - hole_start, hole_len); } - ext_debug(" -> %u:%u\n", lblock, len); - ext4_es_insert_extent(inode, lblock, len, ~0, EXTENT_STATUS_HOLE); + ext_debug(" -> %u:%u\n", hole_start, hole_len); + ext4_es_insert_extent(inode, hole_start, hole_len, ~0, + EXTENT_STATUS_HOLE); } /* @@ -3927,7 +3943,7 @@ get_reserved_cluster_alloc(struct inode *inode, ext4_lblk_t lblk_start, static int convert_initialized_extent(handle_t *handle, struct inode *inode, struct ext4_map_blocks *map, - struct ext4_ext_path **ppath, int flags, + struct ext4_ext_path **ppath, unsigned int allocated) { struct ext4_ext_path *path = *ppath; @@ -4007,7 +4023,6 @@ ext4_ext_handle_unwritten_extents(handle_t *handle, struct inode *inode, struct ext4_ext_path *path = *ppath; int ret = 0; int err = 0; - ext4_io_end_t *io = ext4_inode_aio(inode); ext_debug("ext4_ext_handle_unwritten_extents: inode %lu, logical " "block %llu, max_blocks %u, flags %x, allocated %u\n", @@ -4030,15 +4045,6 @@ ext4_ext_handle_unwritten_extents(handle_t *handle, struct inode *inode, flags | EXT4_GET_BLOCKS_CONVERT); if (ret <= 0) goto out; - /* - * Flag the inode(non aio case) or end_io struct (aio case) - * that this IO needs to conversion to written when IO is - * completed - */ - if (io) - ext4_set_io_unwritten_flag(inode, io); - else - ext4_set_inode_state(inode, EXT4_STATE_DIO_UNWRITTEN); map->m_flags |= EXT4_MAP_UNWRITTEN; goto out; } @@ -4283,9 +4289,7 @@ int ext4_ext_map_blocks(handle_t *handle, struct inode *inode, unsigned int allocated = 0, offset = 0; unsigned int allocated_clusters = 0; struct ext4_allocation_request ar; - ext4_io_end_t *io = ext4_inode_aio(inode); ext4_lblk_t cluster_offset; - int set_unwritten = 0; bool map_from_cluster = false; ext_debug("blocks %u/%u requested for inode %lu\n", @@ -4347,7 +4351,7 @@ int ext4_ext_map_blocks(handle_t *handle, struct inode *inode, (flags & EXT4_GET_BLOCKS_CONVERT_UNWRITTEN)) { allocated = convert_initialized_extent( handle, inode, map, &path, - flags, allocated); + allocated); goto out2; } else if (!ext4_ext_is_unwritten(ex)) goto out; @@ -4368,11 +4372,22 @@ int ext4_ext_map_blocks(handle_t *handle, struct inode *inode, * we couldn't try to create block if create flag is zero */ if ((flags & EXT4_GET_BLOCKS_CREATE) == 0) { + ext4_lblk_t hole_start, hole_len; + + hole_start = map->m_lblk; + hole_len = ext4_ext_determine_hole(inode, path, &hole_start); /* * put just found gap into cache to speed up * subsequent requests */ - ext4_ext_put_gap_in_cache(inode, path, map->m_lblk); + ext4_ext_put_gap_in_cache(inode, hole_start, hole_len); + + /* Update hole_len to reflect hole size after map->m_lblk */ + if (hole_start != map->m_lblk) + hole_len -= map->m_lblk - hole_start; + map->m_pblk = 0; + map->m_len = min_t(unsigned int, map->m_len, hole_len); + goto out2; } @@ -4482,15 +4497,6 @@ got_allocated_blocks: if (flags & EXT4_GET_BLOCKS_UNWRIT_EXT){ ext4_ext_mark_unwritten(&newex); map->m_flags |= EXT4_MAP_UNWRITTEN; - /* - * io_end structure was created for every IO write to an - * unwritten extent. To avoid unnecessary conversion, - * here we flag the IO that really needs the conversion. - * For non asycn direct IO case, flag the inode state - * that we need to perform conversion when IO is done. - */ - if (flags & EXT4_GET_BLOCKS_PRE_IO) - set_unwritten = 1; } err = 0; @@ -4501,14 +4507,6 @@ got_allocated_blocks: err = ext4_ext_insert_extent(handle, inode, &path, &newex, flags); - if (!err && set_unwritten) { - if (io) - ext4_set_io_unwritten_flag(inode, io); - else - ext4_set_inode_state(inode, - EXT4_STATE_DIO_UNWRITTEN); - } - if (err && free_on_err) { int fb_flags = flags & EXT4_GET_BLOCKS_DELALLOC_RESERVE ? EXT4_FREE_BLOCKS_NO_QUOT_UPDATE : 0; -- cgit v1.2.3