/* * GPL HEADER START * * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER. * * This program is free software; you can redistribute it and/or modify * it under the terms of the GNU General Public License version 2 only, * as published by the Free Software Foundation. * * This program is distributed in the hope that it will be useful, but * WITHOUT ANY WARRANTY; without even the implied warranty of * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU * General Public License version 2 for more details (a copy is included * in the LICENSE file that accompanied this code). * * You should have received a copy of the GNU General Public License * version 2 along with this program; If not, see * http://www.sun.com/software/products/lustre/docs/GPLv2.pdf * * Please contact Sun Microsystems, Inc., 4150 Network Circle, Santa Clara, * CA 95054 USA or visit www.sun.com if you need additional information or * have any questions. * * GPL HEADER END */ /* * Copyright (c) 2002, 2010, Oracle and/or its affiliates. All rights reserved. * Use is subject to license terms. * * Copyright (c) 2011, 2013, Intel Corporation. */ /* * This file is part of Lustre, http://www.lustre.org/ * Lustre is a trademark of Sun Microsystems, Inc. * * lustre/lvfs/fsfilt_ext3.c * * Author: Andreas Dilger */ #define DEBUG_SUBSYSTEM S_FILTER #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #ifdef HAVE_EXT_PBLOCK /* Name changed to ext4_ext_pblock for kernel 2.6.35 */ #define ext3_ext_pblock(ex) ext_pblock((ex)) #endif /* for kernels 2.6.18 and later */ #define fsfilt_ext3_ext_insert_extent(handle, inode, path, newext, flag) \ ext3_ext_insert_extent(handle, inode, path, newext, flag) #define ext3_mb_discard_inode_preallocations(inode) \ ext3_discard_preallocations(inode) #ifndef EXT3_EXTENTS_FL #define EXT3_EXTENTS_FL 0x00080000 /* Inode uses extents */ #endif #ifndef EXT_ASSERT #define EXT_ASSERT(cond) BUG_ON(!(cond)) #endif #define EXT_GENERATION(inode) (EXT4_I(inode)->i_ext_generation) #define ext3_ext_base inode #define ext3_ext_base2inode(inode) (inode) #define EXT_DEPTH(inode) ext_depth(inode) #define fsfilt_ext3_ext_walk_space(inode, block, num, cb, cbdata) \ ext3_ext_walk_space(inode, block, num, cb, cbdata); struct bpointers { unsigned long *blocks; unsigned long start; int num; int init_num; int create; }; static long ext3_ext_find_goal(struct inode *inode, struct ext3_ext_path *path, unsigned long block, int *aflags) { struct ext3_inode_info *ei = EXT3_I(inode); unsigned long bg_start; unsigned long colour; int depth; if (path) { struct ext3_extent *ex; depth = path->p_depth; /* try to predict block placement */ if ((ex = path[depth].p_ext)) return ext4_ext_pblock(ex) + (block - le32_to_cpu(ex->ee_block)); /* it looks index is empty * try to find starting from index itself */ if (path[depth].p_bh) return path[depth].p_bh->b_blocknr; } /* OK. use inode's group */ bg_start = (ei->i_block_group * EXT3_BLOCKS_PER_GROUP(inode->i_sb)) + le32_to_cpu(EXT3_SB(inode->i_sb)->s_es->s_first_data_block); colour = (current->pid % 16) * (EXT3_BLOCKS_PER_GROUP(inode->i_sb) / 16); return bg_start + colour + block; } #define ll_unmap_underlying_metadata(sb, blocknr) \ unmap_underlying_metadata((sb)->s_bdev, blocknr) #ifndef EXT3_MB_HINT_GROUP_ALLOC static unsigned long new_blocks(handle_t *handle, struct ext3_ext_base *base, struct ext3_ext_path *path, unsigned long block, unsigned long *count, int *err) { unsigned long pblock, goal; int aflags = 0; struct inode *inode = ext3_ext_base2inode(base); goal = ext3_ext_find_goal(inode, path, block, &aflags); aflags |= 2; /* block have been already reserved */ pblock = ext3_mb_new_blocks(handle, inode, goal, count, aflags, err); return pblock; } #else static unsigned long new_blocks(handle_t *handle, struct ext3_ext_base *base, struct ext3_ext_path *path, unsigned long block, unsigned long *count, int *err) { struct inode *inode = ext3_ext_base2inode(base); struct ext3_allocation_request ar; unsigned long pblock; int aflags; /* find neighbour allocated blocks */ ar.lleft = block; *err = ext3_ext_search_left(base, path, &ar.lleft, &ar.pleft); if (*err) return 0; ar.lright = block; *err = ext3_ext_search_right(base, path, &ar.lright, &ar.pright); if (*err) return 0; /* allocate new block */ ar.goal = ext3_ext_find_goal(inode, path, block, &aflags); ar.inode = inode; ar.logical = block; ar.len = *count; ar.flags = EXT3_MB_HINT_DATA; pblock = ext3_mb_new_blocks(handle, &ar, err); *count = ar.len; return pblock; } #endif static int ext3_ext_new_extent_cb(struct ext3_ext_base *base, struct ext3_ext_path *path, struct ext3_ext_cache *cex, #ifdef HAVE_EXT_PREPARE_CB_EXTENT struct ext3_extent *ex, #endif void *cbdata) { struct bpointers *bp = cbdata; struct inode *inode = ext3_ext_base2inode(base); struct ext3_extent nex; unsigned long pblock; unsigned long tgen; int err, i; unsigned long count; handle_t *handle; #ifdef EXT3_EXT_CACHE_EXTENT if (cex->ec_type == EXT3_EXT_CACHE_EXTENT) #else if ((cex->ec_len != 0) && (cex->ec_start != 0)) #endif { err = EXT_CONTINUE; goto map; } if (bp->create == 0) { i = 0; if (cex->ec_block < bp->start) i = bp->start - cex->ec_block; if (i >= cex->ec_len) CERROR("nothing to do?! i = %d, e_num = %u\n", i, cex->ec_len); for (; i < cex->ec_len && bp->num; i++) { *(bp->blocks) = 0; bp->blocks++; bp->num--; bp->start++; } return EXT_CONTINUE; } tgen = EXT_GENERATION(base); count = ext3_ext_calc_credits_for_insert(base, path); handle = ext3_journal_start(inode, count+EXT3_ALLOC_NEEDED+1); if (IS_ERR(handle)) { return PTR_ERR(handle); } if (tgen != EXT_GENERATION(base)) { /* the tree has changed. so path can be invalid at moment */ ext3_journal_stop(handle); return EXT_REPEAT; } /* In 2.6.32 kernel, ext4_ext_walk_space()'s callback func is not * protected by i_data_sem as whole. so we patch it to store * generation to path and now verify the tree hasn't changed */ down_write((&EXT4_I(inode)->i_data_sem)); /* validate extent, make sure the extent tree does not changed */ if (EXT_GENERATION(base) != path[0].p_generation) { /* cex is invalid, try again */ up_write(&EXT4_I(inode)->i_data_sem); ext3_journal_stop(handle); return EXT_REPEAT; } count = cex->ec_len; pblock = new_blocks(handle, base, path, cex->ec_block, &count, &err); if (!pblock) goto out; EXT_ASSERT(count <= cex->ec_len); /* insert new extent */ nex.ee_block = cpu_to_le32(cex->ec_block); ext3_ext_store_pblock(&nex, pblock); nex.ee_len = cpu_to_le16(count); err = fsfilt_ext3_ext_insert_extent(handle, base, path, &nex, 0); if (err) { /* free data blocks we just allocated */ /* not a good idea to call discard here directly, * but otherwise we'd need to call it every free() */ #ifdef EXT3_MB_HINT_GROUP_ALLOC ext3_mb_discard_inode_preallocations(inode); #endif #ifdef HAVE_EXT_FREE_BLOCK_WITH_BUFFER_HEAD /* Introduced in 2.6.32-rc7 */ ext3_free_blocks(handle, inode, NULL, ext4_ext_pblock(&nex), cpu_to_le16(nex.ee_len), 0); #else ext3_free_blocks(handle, inode, ext4_ext_pblock(&nex), cpu_to_le16(nex.ee_len), 0); #endif goto out; } /* * Putting len of the actual extent we just inserted, * we are asking ext3_ext_walk_space() to continue * scaning after that block */ cex->ec_len = le16_to_cpu(nex.ee_len); cex->ec_start = ext4_ext_pblock(&nex); BUG_ON(le16_to_cpu(nex.ee_len) == 0); BUG_ON(le32_to_cpu(nex.ee_block) != cex->ec_block); out: up_write((&EXT4_I(inode)->i_data_sem)); ext3_journal_stop(handle); map: if (err >= 0) { /* map blocks */ if (bp->num == 0) { CERROR("hmm. why do we find this extent?\n"); CERROR("initial space: %lu:%u\n", bp->start, bp->init_num); #ifdef EXT3_EXT_CACHE_EXTENT CERROR("current extent: %u/%u/%llu %d\n", cex->ec_block, cex->ec_len, (unsigned long long)cex->ec_start, cex->ec_type); #else CERROR("current extent: %u/%u/%llu\n", cex->ec_block, cex->ec_len, (unsigned long long)cex->ec_start); #endif } i = 0; if (cex->ec_block < bp->start) i = bp->start - cex->ec_block; if (i >= cex->ec_len) CERROR("nothing to do?! i = %d, e_num = %u\n", i, cex->ec_len); for (; i < cex->ec_len && bp->num; i++) { *(bp->blocks) = cex->ec_start + i; #ifdef EXT3_EXT_CACHE_EXTENT if (cex->ec_type != EXT3_EXT_CACHE_EXTENT) #else if ((cex->ec_len == 0) || (cex->ec_start == 0)) #endif { /* unmap any possible underlying metadata from * the block device mapping. bug 6998. */ ll_unmap_underlying_metadata(inode->i_sb, *(bp->blocks)); } bp->blocks++; bp->num--; bp->start++; } } return err; } int fsfilt_map_nblocks(struct inode *inode, unsigned long block, unsigned long num, unsigned long *blocks, int create) { struct ext3_ext_base *base = inode; struct bpointers bp; int err; CDEBUG(D_OTHER, "blocks %lu-%lu requested for inode %u\n", block, block + num - 1, (unsigned) inode->i_ino); bp.blocks = blocks; bp.start = block; bp.init_num = bp.num = num; bp.create = create; err = fsfilt_ext3_ext_walk_space(base, block, num, ext3_ext_new_extent_cb, &bp); ext3_ext_invalidate_cache(base); return err; } int fsfilt_ext3_map_ext_inode_pages(struct inode *inode, struct page **page, int pages, unsigned long *blocks, int create) { int blocks_per_page = PAGE_CACHE_SIZE >> inode->i_blkbits; int rc = 0, i = 0; struct page *fp = NULL; int clen = 0; CDEBUG(D_OTHER, "inode %lu: map %d pages from %lu\n", inode->i_ino, pages, (*page)->index); /* pages are sorted already. so, we just have to find * contig. space and process them properly */ while (i < pages) { if (fp == NULL) { /* start new extent */ fp = *page++; clen = 1; i++; continue; } else if (fp->index + clen == (*page)->index) { /* continue the extent */ page++; clen++; i++; continue; } /* process found extent */ rc = fsfilt_map_nblocks(inode, fp->index * blocks_per_page, clen * blocks_per_page, blocks, create); if (rc) GOTO(cleanup, rc); /* look for next extent */ fp = NULL; blocks += blocks_per_page * clen; } if (fp) rc = fsfilt_map_nblocks(inode, fp->index * blocks_per_page, clen * blocks_per_page, blocks, create); cleanup: return rc; } int fsfilt_ext3_map_bm_inode_pages(struct inode *inode, struct page **page, int pages, unsigned long *blocks, int create) { int blocks_per_page = PAGE_CACHE_SIZE >> inode->i_blkbits; unsigned long *b; int rc = 0, i; for (i = 0, b = blocks; i < pages; i++, page++) { rc = ext3_map_inode_page(inode, *page, b, create); if (rc) { CERROR("ino %lu, blk %lu create %d: rc %d\n", inode->i_ino, *b, create, rc); break; } b += blocks_per_page; } return rc; } int fsfilt_ext3_map_inode_pages(struct inode *inode, struct page **page, int pages, unsigned long *blocks, int create, struct mutex *optional_mutex) { int rc; if (EXT3_I(inode)->i_flags & EXT3_EXTENTS_FL) { rc = fsfilt_ext3_map_ext_inode_pages(inode, page, pages, blocks, create); return rc; } if (optional_mutex != NULL) mutex_lock(optional_mutex); rc = fsfilt_ext3_map_bm_inode_pages(inode, page, pages, blocks, create); if (optional_mutex != NULL) mutex_unlock(optional_mutex); return rc; } static struct fsfilt_operations fsfilt_ext3_ops = { .fs_type = "ext3", .fs_owner = THIS_MODULE, .fs_map_inode_pages = fsfilt_ext3_map_inode_pages, }; static int __init fsfilt_ext3_init(void) { return fsfilt_register_ops(&fsfilt_ext3_ops); } static void __exit fsfilt_ext3_exit(void) { fsfilt_unregister_ops(&fsfilt_ext3_ops); } module_init(fsfilt_ext3_init); module_exit(fsfilt_ext3_exit); MODULE_AUTHOR("Sun Microsystems, Inc. "); MODULE_DESCRIPTION("Lustre ext3 Filesystem Helper v0.1"); MODULE_LICENSE("GPL");