linux/fs/nilfs2/direct.c

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/*
* 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"
static inline __le64 *nilfs_direct_dptrs(const struct nilfs_direct *direct)
{
return (__le64 *)
((struct nilfs_direct_node *)direct->d_bmap.b_u.u_data + 1);
}
static inline __u64
nilfs_direct_get_ptr(const struct nilfs_direct *direct, __u64 key)
{
return nilfs_bmap_dptr_to_ptr(*(nilfs_direct_dptrs(direct) + key));
}
static inline void nilfs_direct_set_ptr(struct nilfs_direct *direct,
__u64 key, __u64 ptr)
{
*(nilfs_direct_dptrs(direct) + key) = nilfs_bmap_ptr_to_dptr(ptr);
}
static int nilfs_direct_lookup(const struct nilfs_bmap *bmap,
__u64 key, int level, __u64 *ptrp)
{
struct nilfs_direct *direct;
__u64 ptr;
direct = (struct nilfs_direct *)bmap;
if ((key > NILFS_DIRECT_KEY_MAX) ||
(level != 1) || /* XXX: use macro for level 1 */
((ptr = nilfs_direct_get_ptr(direct, key)) ==
NILFS_BMAP_INVALID_PTR))
return -ENOENT;
if (ptrp != NULL)
*ptrp = ptr;
return 0;
}
static __u64
nilfs_direct_find_target_v(const struct nilfs_direct *direct, __u64 key)
{
__u64 ptr;
ptr = nilfs_bmap_find_target_seq(&direct->d_bmap, key);
if (ptr != NILFS_BMAP_INVALID_PTR)
/* sequential access */
return ptr;
else
/* block group */
return nilfs_bmap_find_target_in_group(&direct->d_bmap);
}
static void nilfs_direct_set_target_v(struct nilfs_direct *direct,
__u64 key, __u64 ptr)
{
direct->d_bmap.b_last_allocated_key = key;
direct->d_bmap.b_last_allocated_ptr = ptr;
}
static int nilfs_direct_prepare_insert(struct nilfs_direct *direct,
__u64 key,
union nilfs_bmap_ptr_req *req,
struct nilfs_bmap_stats *stats)
{
int ret;
if (direct->d_ops->dop_find_target != NULL)
req->bpr_ptr = direct->d_ops->dop_find_target(direct, key);
ret = direct->d_bmap.b_pops->bpop_prepare_alloc_ptr(&direct->d_bmap,
req);
if (ret < 0)
return ret;
stats->bs_nblocks = 1;
return 0;
}
static void nilfs_direct_commit_insert(struct nilfs_direct *direct,
union nilfs_bmap_ptr_req *req,
__u64 key, __u64 ptr)
{
struct buffer_head *bh;
/* ptr must be a pointer to a buffer head. */
bh = (struct buffer_head *)((unsigned long)ptr);
set_buffer_nilfs_volatile(bh);
if (direct->d_bmap.b_pops->bpop_commit_alloc_ptr != NULL)
direct->d_bmap.b_pops->bpop_commit_alloc_ptr(
&direct->d_bmap, req);
nilfs_direct_set_ptr(direct, key, req->bpr_ptr);
if (!nilfs_bmap_dirty(&direct->d_bmap))
nilfs_bmap_set_dirty(&direct->d_bmap);
if (direct->d_ops->dop_set_target != NULL)
direct->d_ops->dop_set_target(direct, key, req->bpr_ptr);
}
static int nilfs_direct_insert(struct nilfs_bmap *bmap, __u64 key, __u64 ptr)
{
struct nilfs_direct *direct;
union nilfs_bmap_ptr_req req;
struct nilfs_bmap_stats stats;
int ret;
direct = (struct nilfs_direct *)bmap;
if (key > NILFS_DIRECT_KEY_MAX)
return -ENOENT;
if (nilfs_direct_get_ptr(direct, key) != NILFS_BMAP_INVALID_PTR)
return -EEXIST;
ret = nilfs_direct_prepare_insert(direct, key, &req, &stats);
if (ret < 0)
return ret;
nilfs_direct_commit_insert(direct, &req, key, ptr);
nilfs_bmap_add_blocks(bmap, stats.bs_nblocks);
return 0;
}
static int nilfs_direct_prepare_delete(struct nilfs_direct *direct,
union nilfs_bmap_ptr_req *req,
__u64 key,
struct nilfs_bmap_stats *stats)
{
int ret;
if (direct->d_bmap.b_pops->bpop_prepare_end_ptr != NULL) {
req->bpr_ptr = nilfs_direct_get_ptr(direct, key);
ret = direct->d_bmap.b_pops->bpop_prepare_end_ptr(
&direct->d_bmap, req);
if (ret < 0)
return ret;
}
stats->bs_nblocks = 1;
return 0;
}
static void nilfs_direct_commit_delete(struct nilfs_direct *direct,
union nilfs_bmap_ptr_req *req,
__u64 key)
{
if (direct->d_bmap.b_pops->bpop_commit_end_ptr != NULL)
direct->d_bmap.b_pops->bpop_commit_end_ptr(
&direct->d_bmap, req);
nilfs_direct_set_ptr(direct, key, NILFS_BMAP_INVALID_PTR);
}
static int nilfs_direct_delete(struct nilfs_bmap *bmap, __u64 key)
{
struct nilfs_direct *direct;
union nilfs_bmap_ptr_req req;
struct nilfs_bmap_stats stats;
int ret;
direct = (struct nilfs_direct *)bmap;
if ((key > NILFS_DIRECT_KEY_MAX) ||
nilfs_direct_get_ptr(direct, key) == NILFS_BMAP_INVALID_PTR)
return -ENOENT;
ret = nilfs_direct_prepare_delete(direct, &req, key, &stats);
if (ret < 0)
return ret;
nilfs_direct_commit_delete(direct, &req, key);
nilfs_bmap_sub_blocks(bmap, stats.bs_nblocks);
return 0;
}
static int nilfs_direct_last_key(const struct nilfs_bmap *bmap, __u64 *keyp)
{
struct nilfs_direct *direct;
__u64 key, lastkey;
direct = (struct nilfs_direct *)bmap;
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;
BUG_ON(keyp == NULL);
*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 *bmap,
__u64 *keys, __u64 *ptrs, int nitems)
{
struct nilfs_direct *direct;
__u64 key;
__u64 ptr;
int n;
direct = (struct nilfs_direct *)bmap;
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, __u64 low, __u64 high)
{
struct nilfs_direct *direct;
__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 */
direct = (struct nilfs_direct *)bmap;
dptrs = nilfs_direct_dptrs(direct);
for (i = 0, j = 0; i < NILFS_DIRECT_NBLOCKS; i++) {
if ((j < n) && (i == keys[j])) {
dptrs[i] = (i != key) ?
nilfs_bmap_ptr_to_dptr(ptrs[j]) :
NILFS_BMAP_INVALID_PTR;
j++;
} else
dptrs[i] = NILFS_BMAP_INVALID_PTR;
}
nilfs_direct_init(bmap, low, high);
return 0;
}
static int nilfs_direct_propagate_v(struct nilfs_direct *direct,
struct buffer_head *bh)
{
union nilfs_bmap_ptr_req oldreq, newreq;
__u64 key;
__u64 ptr;
int ret;
key = nilfs_bmap_data_get_key(&direct->d_bmap, bh);
ptr = nilfs_direct_get_ptr(direct, key);
if (!buffer_nilfs_volatile(bh)) {
oldreq.bpr_ptr = ptr;
newreq.bpr_ptr = ptr;
ret = nilfs_bmap_prepare_update(&direct->d_bmap, &oldreq,
&newreq);
if (ret < 0)
return ret;
nilfs_bmap_commit_update(&direct->d_bmap, &oldreq, &newreq);
set_buffer_nilfs_volatile(bh);
nilfs_direct_set_ptr(direct, key, newreq.bpr_ptr);
} else
ret = nilfs_bmap_mark_dirty(&direct->d_bmap, ptr);
return ret;
}
static int nilfs_direct_propagate(const struct nilfs_bmap *bmap,
struct buffer_head *bh)
{
struct nilfs_direct *direct;
direct = (struct nilfs_direct *)bmap;
return (direct->d_ops->dop_propagate != NULL) ?
direct->d_ops->dop_propagate(direct, bh) :
0;
}
static int nilfs_direct_assign_v(struct nilfs_direct *direct,
__u64 key, __u64 ptr,
struct buffer_head **bh,
sector_t blocknr,
union nilfs_binfo *binfo)
{
union nilfs_bmap_ptr_req req;
int ret;
req.bpr_ptr = ptr;
ret = direct->d_bmap.b_pops->bpop_prepare_start_ptr(
&direct->d_bmap, &req);
if (ret < 0)
return ret;
direct->d_bmap.b_pops->bpop_commit_start_ptr(&direct->d_bmap,
&req, blocknr);
binfo->bi_v.bi_vblocknr = nilfs_bmap_ptr_to_dptr(ptr);
binfo->bi_v.bi_blkoff = nilfs_bmap_key_to_dkey(key);
return 0;
}
static int nilfs_direct_assign_p(struct nilfs_direct *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 = nilfs_bmap_key_to_dkey(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)
{
struct nilfs_direct *direct;
__u64 key;
__u64 ptr;
direct = (struct nilfs_direct *)bmap;
key = nilfs_bmap_data_get_key(bmap, *bh);
BUG_ON(key > NILFS_DIRECT_KEY_MAX);
ptr = nilfs_direct_get_ptr(direct, key);
BUG_ON(ptr == NILFS_BMAP_INVALID_PTR);
return direct->d_ops->dop_assign(direct, key, ptr, bh,
blocknr, binfo);
}
static const struct nilfs_bmap_operations nilfs_direct_ops = {
.bop_lookup = nilfs_direct_lookup,
.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,
};
static const struct nilfs_direct_operations nilfs_direct_ops_v = {
.dop_find_target = nilfs_direct_find_target_v,
.dop_set_target = nilfs_direct_set_target_v,
.dop_propagate = nilfs_direct_propagate_v,
.dop_assign = nilfs_direct_assign_v,
};
static const struct nilfs_direct_operations nilfs_direct_ops_p = {
.dop_find_target = NULL,
.dop_set_target = NULL,
.dop_propagate = NULL,
.dop_assign = nilfs_direct_assign_p,
};
int nilfs_direct_init(struct nilfs_bmap *bmap, __u64 low, __u64 high)
{
struct nilfs_direct *direct;
direct = (struct nilfs_direct *)bmap;
bmap->b_ops = &nilfs_direct_ops;
bmap->b_low = low;
bmap->b_high = high;
switch (bmap->b_inode->i_ino) {
case NILFS_DAT_INO:
direct->d_ops = &nilfs_direct_ops_p;
break;
default:
direct->d_ops = &nilfs_direct_ops_v;
break;
}
return 0;
}