--- /dev/null
+/*
+ * 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_inode_add_blocks(bmap->b_inode, 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_inode_sub_blocks(bmap->b_inode, 1);
+ }
+ return ret;
+}
+
+static int nilfs_direct_seek_key(const struct nilfs_bmap *direct, __u64 start,
+ __u64 *keyp)
+{
+ __u64 key;
+
+ for (key = start; key <= NILFS_DIRECT_KEY_MAX; key++) {
+ if (nilfs_direct_get_ptr(direct, key) !=
+ NILFS_BMAP_INVALID_PTR) {
+ *keyp = key;
+ return 0;
+ }
+ }
+ return -ENOENT;
+}
+
+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_seek_key = nilfs_direct_seek_key,
+ .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;
+}
Code Review / kvmfornfv.git / blobdiff