/* * direct.c - NILFS direct block pointer. * * Copyright (C) 2006-2008 Nippon Telegraph and Telephone Corporation. * * This program is free software; you can redistribute it and/or modify * it under the terms of the GNU General Public License as published by * the Free Software Foundation; either version 2 of the License, or * (at your option) any later version. * * 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 for more details. * * 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., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA * * Written by Koji Sato <koji@osrg.net>. */ #include <linux/errno.h> #include "nilfs.h" #include "page.h" #include "direct.h" #include "alloc.h" #include "dat.h" static inline __le64 *nilfs_direct_dptrs(const struct nilfs_bmap *direct) { return (__le64 *) ((struct nilfs_direct_node *)direct->b_u.u_data + 1); } static inline __u64 nilfs_direct_get_ptr(const struct nilfs_bmap *direct, __u64 key) { return le64_to_cpu(*(nilfs_direct_dptrs(direct) + key)); } static inline void nilfs_direct_set_ptr(struct nilfs_bmap *direct, __u64 key, __u64 ptr) { *(nilfs_direct_dptrs(direct) + key) = cpu_to_le64(ptr); } static int nilfs_direct_lookup(const struct nilfs_bmap *direct, __u64 key, int level, __u64 *ptrp) { __u64 ptr; if (key > NILFS_DIRECT_KEY_MAX || level != 1) return -ENOENT; ptr = nilfs_direct_get_ptr(direct, key); if (ptr == NILFS_BMAP_INVALID_PTR) return -ENOENT; *ptrp = ptr; return 0; } static int nilfs_direct_lookup_contig(const struct nilfs_bmap *direct, __u64 key, __u64 *ptrp, unsigned maxblocks) { struct inode *dat = NULL; __u64 ptr, ptr2; sector_t blocknr; int ret, cnt; if (key > NILFS_DIRECT_KEY_MAX) return -ENOENT; ptr = nilfs_direct_get_ptr(direct, key); if (ptr == NILFS_BMAP_INVALID_PTR) return -ENOENT; if (NILFS_BMAP_USE_VBN(direct)) { dat = nilfs_bmap_get_dat(direct); ret = nilfs_dat_translate(dat, ptr, &blocknr); if (ret < 0) return ret; ptr = blocknr; } maxblocks = min_t(unsigned, maxblocks, NILFS_DIRECT_KEY_MAX - key + 1); for (cnt = 1; cnt < maxblocks && (ptr2 = nilfs_direct_get_ptr(direct, key + cnt)) != NILFS_BMAP_INVALID_PTR; cnt++) { if (dat) { ret = nilfs_dat_translate(dat, ptr2, &blocknr); if (ret < 0) return ret; ptr2 = blocknr; } if (ptr2 != ptr + cnt) break; } *ptrp = ptr; return cnt; } static __u64 nilfs_direct_find_target_v(const struct nilfs_bmap *direct, __u64 key) { __u64 ptr; ptr = nilfs_bmap_find_target_seq(direct, key); if (ptr != NILFS_BMAP_INVALID_PTR) /* sequential access */ return ptr; else /* block group */ return nilfs_bmap_find_target_in_group(direct); } static int nilfs_direct_insert(struct nilfs_bmap *bmap, __u64 key, __u64 ptr) { union nilfs_bmap_ptr_req req; struct inode *dat = NULL; struct buffer_head *bh; int ret; if (key > NILFS_DIRECT_KEY_MAX) return -ENOENT; if (nilfs_direct_get_ptr(bmap, key) != NILFS_BMAP_INVALID_PTR) return -EEXIST; if (NILFS_BMAP_USE_VBN(bmap)) { req.bpr_ptr = nilfs_direct_find_target_v(bmap, key); dat = nilfs_bmap_get_dat(bmap); } ret = nilfs_bmap_prepare_alloc_ptr(bmap, &req, dat); if (!ret) { /* ptr must be a pointer to a buffer head. */ bh = (struct buffer_head *)((unsigned long)ptr); set_buffer_nilfs_volatile(bh); nilfs_bmap_commit_alloc_ptr(bmap, &req, dat); nilfs_direct_set_ptr(bmap, key, req.bpr_ptr); if (!nilfs_bmap_dirty(bmap)) nilfs_bmap_set_dirty(bmap); if (NILFS_BMAP_USE_VBN(bmap)) nilfs_bmap_set_target_v(bmap, key, req.bpr_ptr); nilfs_bmap_add_blocks(bmap, 1); } return ret; } static int nilfs_direct_delete(struct nilfs_bmap *bmap, __u64 key) { union nilfs_bmap_ptr_req req; struct inode *dat; int ret; if (key > NILFS_DIRECT_KEY_MAX || nilfs_direct_get_ptr(bmap, key) == NILFS_BMAP_INVALID_PTR) return -ENOENT; dat = NILFS_BMAP_USE_VBN(bmap) ? nilfs_bmap_get_dat(bmap) : NULL; req.bpr_ptr = nilfs_direct_get_ptr(bmap, key); ret = nilfs_bmap_prepare_end_ptr(bmap, &req, dat); if (!ret) { nilfs_bmap_commit_end_ptr(bmap, &req, dat); nilfs_direct_set_ptr(bmap, key, NILFS_BMAP_INVALID_PTR); nilfs_bmap_sub_blocks(bmap, 1); } return ret; } static int nilfs_direct_last_key(const struct nilfs_bmap *direct, __u64 *keyp) { __u64 key, lastkey; lastkey = NILFS_DIRECT_KEY_MAX + 1; for (key = NILFS_DIRECT_KEY_MIN; key <= NILFS_DIRECT_KEY_MAX; key++) if (nilfs_direct_get_ptr(direct, key) != NILFS_BMAP_INVALID_PTR) lastkey = key; if (lastkey == NILFS_DIRECT_KEY_MAX + 1) return -ENOENT; *keyp = lastkey; return 0; } static int nilfs_direct_check_insert(const struct nilfs_bmap *bmap, __u64 key) { return key > NILFS_DIRECT_KEY_MAX; } static int nilfs_direct_gather_data(struct nilfs_bmap *direct, __u64 *keys, __u64 *ptrs, int nitems) { __u64 key; __u64 ptr; int n; if (nitems > NILFS_DIRECT_NBLOCKS) nitems = NILFS_DIRECT_NBLOCKS; n = 0; for (key = 0; key < nitems; key++) { ptr = nilfs_direct_get_ptr(direct, key); if (ptr != NILFS_BMAP_INVALID_PTR) { keys[n] = key; ptrs[n] = ptr; n++; } } return n; } int nilfs_direct_delete_and_convert(struct nilfs_bmap *bmap, __u64 key, __u64 *keys, __u64 *ptrs, int n) { __le64 *dptrs; int ret, i, j; /* no need to allocate any resource for conversion */ /* delete */ ret = bmap->b_ops->bop_delete(bmap, key); if (ret < 0) return ret; /* free resources */ if (bmap->b_ops->bop_clear != NULL) bmap->b_ops->bop_clear(bmap); /* convert */ dptrs = nilfs_direct_dptrs(bmap); for (i = 0, j = 0; i < NILFS_DIRECT_NBLOCKS; i++) { if ((j < n) && (i == keys[j])) { dptrs[i] = (i != key) ? cpu_to_le64(ptrs[j]) : NILFS_BMAP_INVALID_PTR; j++; } else dptrs[i] = NILFS_BMAP_INVALID_PTR; } nilfs_direct_init(bmap); return 0; } static int nilfs_direct_propagate(struct nilfs_bmap *bmap, struct buffer_head *bh) { struct nilfs_palloc_req oldreq, newreq; struct inode *dat; __u64 key; __u64 ptr; int ret; if (!NILFS_BMAP_USE_VBN(bmap)) return 0; dat = nilfs_bmap_get_dat(bmap); key = nilfs_bmap_data_get_key(bmap, bh); ptr = nilfs_direct_get_ptr(bmap, key); if (!buffer_nilfs_volatile(bh)) { oldreq.pr_entry_nr = ptr; newreq.pr_entry_nr = ptr; ret = nilfs_dat_prepare_update(dat, &oldreq, &newreq); if (ret < 0) return ret; nilfs_dat_commit_update(dat, &oldreq, &newreq, bmap->b_ptr_type == NILFS_BMAP_PTR_VS); set_buffer_nilfs_volatile(bh); nilfs_direct_set_ptr(bmap, key, newreq.pr_entry_nr); } else ret = nilfs_dat_mark_dirty(dat, ptr); return ret; } static int nilfs_direct_assign_v(struct nilfs_bmap *direct, __u64 key, __u64 ptr, struct buffer_head **bh, sector_t blocknr, union nilfs_binfo *binfo) { struct inode *dat = nilfs_bmap_get_dat(direct); union nilfs_bmap_ptr_req req; int ret; req.bpr_ptr = ptr; ret = nilfs_dat_prepare_start(dat, &req.bpr_req); if (!ret) { nilfs_dat_commit_start(dat, &req.bpr_req, blocknr); binfo->bi_v.bi_vblocknr = cpu_to_le64(ptr); binfo->bi_v.bi_blkoff = cpu_to_le64(key); } return ret; } static int nilfs_direct_assign_p(struct nilfs_bmap *direct, __u64 key, __u64 ptr, struct buffer_head **bh, sector_t blocknr, union nilfs_binfo *binfo) { nilfs_direct_set_ptr(direct, key, blocknr); binfo->bi_dat.bi_blkoff = cpu_to_le64(key); binfo->bi_dat.bi_level = 0; return 0; } static int nilfs_direct_assign(struct nilfs_bmap *bmap, struct buffer_head **bh, sector_t blocknr, union nilfs_binfo *binfo) { __u64 key; __u64 ptr; key = nilfs_bmap_data_get_key(bmap, *bh); if (unlikely(key > NILFS_DIRECT_KEY_MAX)) { printk(KERN_CRIT "%s: invalid key: %llu\n", __func__, (unsigned long long)key); return -EINVAL; } ptr = nilfs_direct_get_ptr(bmap, key); if (unlikely(ptr == NILFS_BMAP_INVALID_PTR)) { printk(KERN_CRIT "%s: invalid pointer: %llu\n", __func__, (unsigned long long)ptr); return -EINVAL; } return NILFS_BMAP_USE_VBN(bmap) ? nilfs_direct_assign_v(bmap, key, ptr, bh, blocknr, binfo) : nilfs_direct_assign_p(bmap, key, ptr, bh, blocknr, binfo); } static const struct nilfs_bmap_operations nilfs_direct_ops = { .bop_lookup = nilfs_direct_lookup, .bop_lookup_contig = nilfs_direct_lookup_contig, .bop_insert = nilfs_direct_insert, .bop_delete = nilfs_direct_delete, .bop_clear = NULL, .bop_propagate = nilfs_direct_propagate, .bop_lookup_dirty_buffers = NULL, .bop_assign = nilfs_direct_assign, .bop_mark = NULL, .bop_last_key = nilfs_direct_last_key, .bop_check_insert = nilfs_direct_check_insert, .bop_check_delete = NULL, .bop_gather_data = nilfs_direct_gather_data, }; int nilfs_direct_init(struct nilfs_bmap *bmap) { bmap->b_ops = &nilfs_direct_ops; return 0; }