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linux/fs/ocfs2/move_extents.c
Al Viro f6a5690324 ocfs2: deal with __user misannotations 
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2012-05-29 23:28:35 -04:00

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/* -*- mode: c; c-basic-offset: 8; -*-
* vim: noexpandtab sw=8 ts=8 sts=0:
*
* move_extents.c
*
* Copyright (C) 2011 Oracle. All rights reserved.
*
* This program is free software; you can redistribute it and/or
* modify it under the terms of the GNU General Public
* License version 2 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 for more details.
*/
#include <linux/fs.h>
#include <linux/types.h>
#include <linux/mount.h>
#include <linux/swap.h>
#include <cluster/masklog.h>
#include "ocfs2.h"
#include "ocfs2_ioctl.h"
#include "alloc.h"
#include "aops.h"
#include "dlmglue.h"
#include "extent_map.h"
#include "inode.h"
#include "journal.h"
#include "suballoc.h"
#include "uptodate.h"
#include "super.h"
#include "dir.h"
#include "buffer_head_io.h"
#include "sysfile.h"
#include "refcounttree.h"
#include "move_extents.h"
struct ocfs2_move_extents_context {
struct inode *inode;
struct file *file;
int auto_defrag;
int partial;
int credits;
u32 new_phys_cpos;
u32 clusters_moved;
u64 refcount_loc;
struct ocfs2_move_extents *range;
struct ocfs2_extent_tree et;
struct ocfs2_alloc_context *meta_ac;
struct ocfs2_alloc_context *data_ac;
struct ocfs2_cached_dealloc_ctxt dealloc;
};
static int __ocfs2_move_extent(handle_t *handle,
struct ocfs2_move_extents_context *context,
u32 cpos, u32 len, u32 p_cpos, u32 new_p_cpos,
int ext_flags)
{
int ret = 0, index;
struct inode *inode = context->inode;
struct ocfs2_super *osb = OCFS2_SB(inode->i_sb);
struct ocfs2_extent_rec *rec, replace_rec;
struct ocfs2_path *path = NULL;
struct ocfs2_extent_list *el;
u64 ino = ocfs2_metadata_cache_owner(context->et.et_ci);
u64 old_blkno = ocfs2_clusters_to_blocks(inode->i_sb, p_cpos);
ret = ocfs2_duplicate_clusters_by_page(handle, context->file, cpos,
p_cpos, new_p_cpos, len);
if (ret) {
mlog_errno(ret);
goto out;
}
memset(&replace_rec, 0, sizeof(replace_rec));
replace_rec.e_cpos = cpu_to_le32(cpos);
replace_rec.e_leaf_clusters = cpu_to_le16(len);
replace_rec.e_blkno = cpu_to_le64(ocfs2_clusters_to_blocks(inode->i_sb,
new_p_cpos));
path = ocfs2_new_path_from_et(&context->et);
if (!path) {
ret = -ENOMEM;
mlog_errno(ret);
goto out;
}
ret = ocfs2_find_path(INODE_CACHE(inode), path, cpos);
if (ret) {
mlog_errno(ret);
goto out;
}
el = path_leaf_el(path);
index = ocfs2_search_extent_list(el, cpos);
if (index == -1 || index >= le16_to_cpu(el->l_next_free_rec)) {
ocfs2_error(inode->i_sb,
"Inode %llu has an extent at cpos %u which can no "
"longer be found.\n",
(unsigned long long)ino, cpos);
ret = -EROFS;
goto out;
}
rec = &el->l_recs[index];
BUG_ON(ext_flags != rec->e_flags);
/*
* after moving/defraging to new location, the extent is not going
* to be refcounted anymore.
*/
replace_rec.e_flags = ext_flags & ~OCFS2_EXT_REFCOUNTED;
ret = ocfs2_journal_access_di(handle, INODE_CACHE(inode),
context->et.et_root_bh,
OCFS2_JOURNAL_ACCESS_WRITE);
if (ret) {
mlog_errno(ret);
goto out;
}
ret = ocfs2_split_extent(handle, &context->et, path, index,
&replace_rec, context->meta_ac,
&context->dealloc);
if (ret) {
mlog_errno(ret);
goto out;
}
ocfs2_journal_dirty(handle, context->et.et_root_bh);
context->new_phys_cpos = new_p_cpos;
/*
* need I to append truncate log for old clusters?
*/
if (old_blkno) {
if (ext_flags & OCFS2_EXT_REFCOUNTED)
ret = ocfs2_decrease_refcount(inode, handle,
ocfs2_blocks_to_clusters(osb->sb,
old_blkno),
len, context->meta_ac,
&context->dealloc, 1);
else
ret = ocfs2_truncate_log_append(osb, handle,
old_blkno, len);
}
out:
return ret;
}
/*
* lock allocators, and reserving appropriate number of bits for
* meta blocks and data clusters.
*
* in some cases, we don't need to reserve clusters, just let data_ac
* be NULL.
*/
static int ocfs2_lock_allocators_move_extents(struct inode *inode,
struct ocfs2_extent_tree *et,
u32 clusters_to_move,
u32 extents_to_split,
struct ocfs2_alloc_context **meta_ac,
struct ocfs2_alloc_context **data_ac,
int extra_blocks,
int *credits)
{
int ret, num_free_extents;
unsigned int max_recs_needed = 2 * extents_to_split + clusters_to_move;
struct ocfs2_super *osb = OCFS2_SB(inode->i_sb);
num_free_extents = ocfs2_num_free_extents(osb, et);
if (num_free_extents < 0) {
ret = num_free_extents;
mlog_errno(ret);
goto out;
}
if (!num_free_extents ||
(ocfs2_sparse_alloc(osb) && num_free_extents < max_recs_needed))
extra_blocks += ocfs2_extend_meta_needed(et->et_root_el);
ret = ocfs2_reserve_new_metadata_blocks(osb, extra_blocks, meta_ac);
if (ret) {
mlog_errno(ret);
goto out;
}
if (data_ac) {
ret = ocfs2_reserve_clusters(osb, clusters_to_move, data_ac);
if (ret) {
mlog_errno(ret);
goto out;
}
}
*credits += ocfs2_calc_extend_credits(osb->sb, et->et_root_el,
clusters_to_move + 2);
mlog(0, "reserve metadata_blocks: %d, data_clusters: %u, credits: %d\n",
extra_blocks, clusters_to_move, *credits);
out:
if (ret) {
if (*meta_ac) {
ocfs2_free_alloc_context(*meta_ac);
*meta_ac = NULL;
}
}
return ret;
}
/*
* Using one journal handle to guarantee the data consistency in case
* crash happens anywhere.
*
* XXX: defrag can end up with finishing partial extent as requested,
* due to not enough contiguous clusters can be found in allocator.
*/
static int ocfs2_defrag_extent(struct ocfs2_move_extents_context *context,
u32 cpos, u32 phys_cpos, u32 *len, int ext_flags)
{
int ret, credits = 0, extra_blocks = 0, partial = context->partial;
handle_t *handle;
struct inode *inode = context->inode;
struct ocfs2_super *osb = OCFS2_SB(inode->i_sb);
struct inode *tl_inode = osb->osb_tl_inode;
struct ocfs2_refcount_tree *ref_tree = NULL;
u32 new_phys_cpos, new_len;
u64 phys_blkno = ocfs2_clusters_to_blocks(inode->i_sb, phys_cpos);
if ((ext_flags & OCFS2_EXT_REFCOUNTED) && *len) {
BUG_ON(!(OCFS2_I(inode)->ip_dyn_features &
OCFS2_HAS_REFCOUNT_FL));
BUG_ON(!context->refcount_loc);
ret = ocfs2_lock_refcount_tree(osb, context->refcount_loc, 1,
&ref_tree, NULL);
if (ret) {
mlog_errno(ret);
return ret;
}
ret = ocfs2_prepare_refcount_change_for_del(inode,
context->refcount_loc,
phys_blkno,
*len,
&credits,
&extra_blocks);
if (ret) {
mlog_errno(ret);
goto out;
}
}
ret = ocfs2_lock_allocators_move_extents(inode, &context->et, *len, 1,
&context->meta_ac,
&context->data_ac,
extra_blocks, &credits);
if (ret) {
mlog_errno(ret);
goto out;
}
/*
* should be using allocation reservation strategy there?
*
* if (context->data_ac)
* context->data_ac->ac_resv = &OCFS2_I(inode)->ip_la_data_resv;
*/
mutex_lock(&tl_inode->i_mutex);
if (ocfs2_truncate_log_needs_flush(osb)) {
ret = __ocfs2_flush_truncate_log(osb);
if (ret < 0) {
mlog_errno(ret);
goto out_unlock_mutex;
}
}
handle = ocfs2_start_trans(osb, credits);
if (IS_ERR(handle)) {
ret = PTR_ERR(handle);
mlog_errno(ret);
goto out_unlock_mutex;
}
ret = __ocfs2_claim_clusters(handle, context->data_ac, 1, *len,
&new_phys_cpos, &new_len);
if (ret) {
mlog_errno(ret);
goto out_commit;
}
/*
* allowing partial extent moving is kind of 'pros and cons', it makes
* whole defragmentation less likely to fail, on the contrary, the bad
* thing is it may make the fs even more fragmented after moving, let
* userspace make a good decision here.
*/
if (new_len != *len) {
mlog(0, "len_claimed: %u, len: %u\n", new_len, *len);
if (!partial) {
context->range->me_flags &= ~OCFS2_MOVE_EXT_FL_COMPLETE;
ret = -ENOSPC;
goto out_commit;
}
}
mlog(0, "cpos: %u, phys_cpos: %u, new_phys_cpos: %u\n", cpos,
phys_cpos, new_phys_cpos);
ret = __ocfs2_move_extent(handle, context, cpos, new_len, phys_cpos,
new_phys_cpos, ext_flags);
if (ret)
mlog_errno(ret);
if (partial && (new_len != *len))
*len = new_len;
/*
* Here we should write the new page out first if we are
* in write-back mode.
*/
ret = ocfs2_cow_sync_writeback(inode->i_sb, context->inode, cpos, *len);
if (ret)
mlog_errno(ret);
out_commit:
ocfs2_commit_trans(osb, handle);
out_unlock_mutex:
mutex_unlock(&tl_inode->i_mutex);
if (context->data_ac) {
ocfs2_free_alloc_context(context->data_ac);
context->data_ac = NULL;
}
if (context->meta_ac) {
ocfs2_free_alloc_context(context->meta_ac);
context->meta_ac = NULL;
}
out:
if (ref_tree)
ocfs2_unlock_refcount_tree(osb, ref_tree, 1);
return ret;
}
/*
* find the victim alloc group, where #blkno fits.
*/
static int ocfs2_find_victim_alloc_group(struct inode *inode,
u64 vict_blkno,
int type, int slot,
int *vict_bit,
struct buffer_head **ret_bh)
{
int ret, i, bits_per_unit = 0;
u64 blkno;
char namebuf[40];
struct ocfs2_super *osb = OCFS2_SB(inode->i_sb);
struct buffer_head *ac_bh = NULL, *gd_bh = NULL;
struct ocfs2_chain_list *cl;
struct ocfs2_chain_rec *rec;
struct ocfs2_dinode *ac_dinode;
struct ocfs2_group_desc *bg;
ocfs2_sprintf_system_inode_name(namebuf, sizeof(namebuf), type, slot);
ret = ocfs2_lookup_ino_from_name(osb->sys_root_inode, namebuf,
strlen(namebuf), &blkno);
if (ret) {
ret = -ENOENT;
goto out;
}
ret = ocfs2_read_blocks_sync(osb, blkno, 1, &ac_bh);
if (ret) {
mlog_errno(ret);
goto out;
}
ac_dinode = (struct ocfs2_dinode *)ac_bh->b_data;
cl = &(ac_dinode->id2.i_chain);
rec = &(cl->cl_recs[0]);
if (type == GLOBAL_BITMAP_SYSTEM_INODE)
bits_per_unit = osb->s_clustersize_bits -
inode->i_sb->s_blocksize_bits;
/*
* 'vict_blkno' was out of the valid range.
*/
if ((vict_blkno < le64_to_cpu(rec->c_blkno)) ||
(vict_blkno >= (le32_to_cpu(ac_dinode->id1.bitmap1.i_total) <<
bits_per_unit))) {
ret = -EINVAL;
goto out;
}
for (i = 0; i < le16_to_cpu(cl->cl_next_free_rec); i++) {
rec = &(cl->cl_recs[i]);
if (!rec)
continue;
bg = NULL;
do {
if (!bg)
blkno = le64_to_cpu(rec->c_blkno);
else
blkno = le64_to_cpu(bg->bg_next_group);
if (gd_bh) {
brelse(gd_bh);
gd_bh = NULL;
}
ret = ocfs2_read_blocks_sync(osb, blkno, 1, &gd_bh);
if (ret) {
mlog_errno(ret);
goto out;
}
bg = (struct ocfs2_group_desc *)gd_bh->b_data;
if (vict_blkno < (le64_to_cpu(bg->bg_blkno) +
le16_to_cpu(bg->bg_bits))) {
*ret_bh = gd_bh;
*vict_bit = (vict_blkno - blkno) >>
bits_per_unit;
mlog(0, "find the victim group: #%llu, "
"total_bits: %u, vict_bit: %u\n",
blkno, le16_to_cpu(bg->bg_bits),
*vict_bit);
goto out;
}
} while (le64_to_cpu(bg->bg_next_group));
}
ret = -EINVAL;
out:
brelse(ac_bh);
/*
* caller has to release the gd_bh properly.
*/
return ret;
}
/*
* XXX: helper to validate and adjust moving goal.
*/
static int ocfs2_validate_and_adjust_move_goal(struct inode *inode,
struct ocfs2_move_extents *range)
{
int ret, goal_bit = 0;
struct buffer_head *gd_bh = NULL;
struct ocfs2_group_desc *bg = NULL;
struct ocfs2_super *osb = OCFS2_SB(inode->i_sb);
int c_to_b = 1 << (osb->s_clustersize_bits -
inode->i_sb->s_blocksize_bits);
/*
* make goal become cluster aligned.
*/
range->me_goal = ocfs2_block_to_cluster_start(inode->i_sb,
range->me_goal);
/*
* moving goal is not allowd to start with a group desc blok(#0 blk)
* let's compromise to the latter cluster.
*/
if (range->me_goal == le64_to_cpu(bg->bg_blkno))
range->me_goal += c_to_b;
/*
* validate goal sits within global_bitmap, and return the victim
* group desc
*/
ret = ocfs2_find_victim_alloc_group(inode, range->me_goal,
GLOBAL_BITMAP_SYSTEM_INODE,
OCFS2_INVALID_SLOT,
&goal_bit, &gd_bh);
if (ret)
goto out;
bg = (struct ocfs2_group_desc *)gd_bh->b_data;
/*
* movement is not gonna cross two groups.
*/
if ((le16_to_cpu(bg->bg_bits) - goal_bit) * osb->s_clustersize <
range->me_len) {
ret = -EINVAL;
goto out;
}
/*
* more exact validations/adjustments will be performed later during
* moving operation for each extent range.
*/
mlog(0, "extents get ready to be moved to #%llu block\n",
range->me_goal);
out:
brelse(gd_bh);
return ret;
}
static void ocfs2_probe_alloc_group(struct inode *inode, struct buffer_head *bh,
int *goal_bit, u32 move_len, u32 max_hop,
u32 *phys_cpos)
{
int i, used, last_free_bits = 0, base_bit = *goal_bit;
struct ocfs2_group_desc *gd = (struct ocfs2_group_desc *)bh->b_data;
u32 base_cpos = ocfs2_blocks_to_clusters(inode->i_sb,
le64_to_cpu(gd->bg_blkno));
for (i = base_bit; i < le16_to_cpu(gd->bg_bits); i++) {
used = ocfs2_test_bit(i, (unsigned long *)gd->bg_bitmap);
if (used) {
/*
* we even tried searching the free chunk by jumping
* a 'max_hop' distance, but still failed.
*/
if ((i - base_bit) > max_hop) {
*phys_cpos = 0;
break;
}
if (last_free_bits)
last_free_bits = 0;
continue;
} else
last_free_bits++;
if (last_free_bits == move_len) {
*goal_bit = i;
*phys_cpos = base_cpos + i;
break;
}
}
mlog(0, "found phys_cpos: %u to fit the wanted moving.\n", *phys_cpos);
}
static int ocfs2_alloc_dinode_update_counts(struct inode *inode,
handle_t *handle,
struct buffer_head *di_bh,
u32 num_bits,
u16 chain)
{
int ret;
u32 tmp_used;
struct ocfs2_dinode *di = (struct ocfs2_dinode *) di_bh->b_data;
struct ocfs2_chain_list *cl =
(struct ocfs2_chain_list *) &di->id2.i_chain;
ret = ocfs2_journal_access_di(handle, INODE_CACHE(inode), di_bh,
OCFS2_JOURNAL_ACCESS_WRITE);
if (ret < 0) {
mlog_errno(ret);
goto out;
}
tmp_used = le32_to_cpu(di->id1.bitmap1.i_used);
di->id1.bitmap1.i_used = cpu_to_le32(num_bits + tmp_used);
le32_add_cpu(&cl->cl_recs[chain].c_free, -num_bits);
ocfs2_journal_dirty(handle, di_bh);
out:
return ret;
}
static inline int ocfs2_block_group_set_bits(handle_t *handle,
struct inode *alloc_inode,
struct ocfs2_group_desc *bg,
struct buffer_head *group_bh,
unsigned int bit_off,
unsigned int num_bits)
{
int status;
void *bitmap = bg->bg_bitmap;
int journal_type = OCFS2_JOURNAL_ACCESS_WRITE;
/* All callers get the descriptor via
* ocfs2_read_group_descriptor(). Any corruption is a code bug. */
BUG_ON(!OCFS2_IS_VALID_GROUP_DESC(bg));
BUG_ON(le16_to_cpu(bg->bg_free_bits_count) < num_bits);
mlog(0, "block_group_set_bits: off = %u, num = %u\n", bit_off,
num_bits);
if (ocfs2_is_cluster_bitmap(alloc_inode))
journal_type = OCFS2_JOURNAL_ACCESS_UNDO;
status = ocfs2_journal_access_gd(handle,
INODE_CACHE(alloc_inode),
group_bh,
journal_type);
if (status < 0) {
mlog_errno(status);
goto bail;
}
le16_add_cpu(&bg->bg_free_bits_count, -num_bits);
if (le16_to_cpu(bg->bg_free_bits_count) > le16_to_cpu(bg->bg_bits)) {
ocfs2_error(alloc_inode->i_sb, "Group descriptor # %llu has bit"
" count %u but claims %u are freed. num_bits %d",
(unsigned long long)le64_to_cpu(bg->bg_blkno),
le16_to_cpu(bg->bg_bits),
le16_to_cpu(bg->bg_free_bits_count), num_bits);
return -EROFS;
}
while (num_bits--)
ocfs2_set_bit(bit_off++, bitmap);
ocfs2_journal_dirty(handle, group_bh);
bail:
return status;
}
static int ocfs2_move_extent(struct ocfs2_move_extents_context *context,
u32 cpos, u32 phys_cpos, u32 *new_phys_cpos,
u32 len, int ext_flags)
{
int ret, credits = 0, extra_blocks = 0, goal_bit = 0;
handle_t *handle;
struct inode *inode = context->inode;
struct ocfs2_super *osb = OCFS2_SB(inode->i_sb);
struct inode *tl_inode = osb->osb_tl_inode;
struct inode *gb_inode = NULL;
struct buffer_head *gb_bh = NULL;
struct buffer_head *gd_bh = NULL;
struct ocfs2_group_desc *gd;
struct ocfs2_refcount_tree *ref_tree = NULL;
u32 move_max_hop = ocfs2_blocks_to_clusters(inode->i_sb,
context->range->me_threshold);
u64 phys_blkno, new_phys_blkno;
phys_blkno = ocfs2_clusters_to_blocks(inode->i_sb, phys_cpos);
if ((ext_flags & OCFS2_EXT_REFCOUNTED) && len) {
BUG_ON(!(OCFS2_I(inode)->ip_dyn_features &
OCFS2_HAS_REFCOUNT_FL));
BUG_ON(!context->refcount_loc);
ret = ocfs2_lock_refcount_tree(osb, context->refcount_loc, 1,
&ref_tree, NULL);
if (ret) {
mlog_errno(ret);
return ret;
}
ret = ocfs2_prepare_refcount_change_for_del(inode,
context->refcount_loc,
phys_blkno,
len,
&credits,
&extra_blocks);
if (ret) {
mlog_errno(ret);
goto out;
}
}
ret = ocfs2_lock_allocators_move_extents(inode, &context->et, len, 1,
&context->meta_ac,
NULL, extra_blocks, &credits);
if (ret) {
mlog_errno(ret);
goto out;
}
/*
* need to count 2 extra credits for global_bitmap inode and
* group descriptor.
*/
credits += OCFS2_INODE_UPDATE_CREDITS + 1;
/*
* ocfs2_move_extent() didn't reserve any clusters in lock_allocators()
* logic, while we still need to lock the global_bitmap.
*/
gb_inode = ocfs2_get_system_file_inode(osb, GLOBAL_BITMAP_SYSTEM_INODE,
OCFS2_INVALID_SLOT);
if (!gb_inode) {
mlog(ML_ERROR, "unable to get global_bitmap inode\n");
ret = -EIO;
goto out;
}
mutex_lock(&gb_inode->i_mutex);
ret = ocfs2_inode_lock(gb_inode, &gb_bh, 1);
if (ret) {
mlog_errno(ret);
goto out_unlock_gb_mutex;
}
mutex_lock(&tl_inode->i_mutex);
handle = ocfs2_start_trans(osb, credits);
if (IS_ERR(handle)) {
ret = PTR_ERR(handle);
mlog_errno(ret);
goto out_unlock_tl_inode;
}
new_phys_blkno = ocfs2_clusters_to_blocks(inode->i_sb, *new_phys_cpos);
ret = ocfs2_find_victim_alloc_group(inode, new_phys_blkno,
GLOBAL_BITMAP_SYSTEM_INODE,
OCFS2_INVALID_SLOT,
&goal_bit, &gd_bh);
if (ret) {
mlog_errno(ret);
goto out_commit;
}
/*
* probe the victim cluster group to find a proper
* region to fit wanted movement, it even will perfrom
* a best-effort attempt by compromising to a threshold
* around the goal.
*/
ocfs2_probe_alloc_group(inode, gd_bh, &goal_bit, len, move_max_hop,
new_phys_cpos);
if (!*new_phys_cpos) {
ret = -ENOSPC;
goto out_commit;
}
ret = __ocfs2_move_extent(handle, context, cpos, len, phys_cpos,
*new_phys_cpos, ext_flags);
if (ret) {
mlog_errno(ret);
goto out_commit;
}
gd = (struct ocfs2_group_desc *)gd_bh->b_data;
ret = ocfs2_alloc_dinode_update_counts(gb_inode, handle, gb_bh, len,
le16_to_cpu(gd->bg_chain));
if (ret) {
mlog_errno(ret);
goto out_commit;
}
ret = ocfs2_block_group_set_bits(handle, gb_inode, gd, gd_bh,
goal_bit, len);
if (ret)
mlog_errno(ret);
/*
* Here we should write the new page out first if we are
* in write-back mode.
*/
ret = ocfs2_cow_sync_writeback(inode->i_sb, context->inode, cpos, len);
if (ret)
mlog_errno(ret);
out_commit:
ocfs2_commit_trans(osb, handle);
brelse(gd_bh);
out_unlock_tl_inode:
mutex_unlock(&tl_inode->i_mutex);
ocfs2_inode_unlock(gb_inode, 1);
out_unlock_gb_mutex:
mutex_unlock(&gb_inode->i_mutex);
brelse(gb_bh);
iput(gb_inode);
out:
if (context->meta_ac) {
ocfs2_free_alloc_context(context->meta_ac);
context->meta_ac = NULL;
}
if (ref_tree)
ocfs2_unlock_refcount_tree(osb, ref_tree, 1);
return ret;
}
/*
* Helper to calculate the defraging length in one run according to threshold.
*/
static void ocfs2_calc_extent_defrag_len(u32 *alloc_size, u32 *len_defraged,
u32 threshold, int *skip)
{
if ((*alloc_size + *len_defraged) < threshold) {
/*
* proceed defragmentation until we meet the thresh
*/
*len_defraged += *alloc_size;
} else if (*len_defraged == 0) {
/*
* XXX: skip a large extent.
*/
*skip = 1;
} else {
/*
* split this extent to coalesce with former pieces as
* to reach the threshold.
*
* we're done here with one cycle of defragmentation
* in a size of 'thresh', resetting 'len_defraged'
* forces a new defragmentation.
*/
*alloc_size = threshold - *len_defraged;
*len_defraged = 0;
}
}
static int __ocfs2_move_extents_range(struct buffer_head *di_bh,
struct ocfs2_move_extents_context *context)
{
int ret = 0, flags, do_defrag, skip = 0;
u32 cpos, phys_cpos, move_start, len_to_move, alloc_size;
u32 len_defraged = 0, defrag_thresh = 0, new_phys_cpos = 0;
struct inode *inode = context->inode;
struct ocfs2_dinode *di = (struct ocfs2_dinode *)di_bh->b_data;
struct ocfs2_move_extents *range = context->range;
struct ocfs2_super *osb = OCFS2_SB(inode->i_sb);
if ((inode->i_size == 0) || (range->me_len == 0))
return 0;
if (OCFS2_I(inode)->ip_dyn_features & OCFS2_INLINE_DATA_FL)
return 0;
context->refcount_loc = le64_to_cpu(di->i_refcount_loc);
ocfs2_init_dinode_extent_tree(&context->et, INODE_CACHE(inode), di_bh);
ocfs2_init_dealloc_ctxt(&context->dealloc);
/*
* TO-DO XXX:
*
* - xattr extents.
*/
do_defrag = context->auto_defrag;
/*
* extents moving happens in unit of clusters, for the sake
* of simplicity, we may ignore two clusters where 'byte_start'
* and 'byte_start + len' were within.
*/
move_start = ocfs2_clusters_for_bytes(osb->sb, range->me_start);
len_to_move = (range->me_start + range->me_len) >>
osb->s_clustersize_bits;
if (len_to_move >= move_start)
len_to_move -= move_start;
else
len_to_move = 0;
if (do_defrag) {
defrag_thresh = range->me_threshold >> osb->s_clustersize_bits;
if (defrag_thresh <= 1)
goto done;
} else
new_phys_cpos = ocfs2_blocks_to_clusters(inode->i_sb,
range->me_goal);
mlog(0, "Inode: %llu, start: %llu, len: %llu, cstart: %u, clen: %u, "
"thresh: %u\n",
(unsigned long long)OCFS2_I(inode)->ip_blkno,
(unsigned long long)range->me_start,
(unsigned long long)range->me_len,
move_start, len_to_move, defrag_thresh);
cpos = move_start;
while (len_to_move) {
ret = ocfs2_get_clusters(inode, cpos, &phys_cpos, &alloc_size,
&flags);
if (ret) {
mlog_errno(ret);
goto out;
}
if (alloc_size > len_to_move)
alloc_size = len_to_move;
/*
* XXX: how to deal with a hole:
*
* - skip the hole of course
* - force a new defragmentation
*/
if (!phys_cpos) {
if (do_defrag)
len_defraged = 0;
goto next;
}
if (do_defrag) {
ocfs2_calc_extent_defrag_len(&alloc_size, &len_defraged,
defrag_thresh, &skip);
/*
* skip large extents
*/
if (skip) {
skip = 0;
goto next;
}
mlog(0, "#Defrag: cpos: %u, phys_cpos: %u, "
"alloc_size: %u, len_defraged: %u\n",
cpos, phys_cpos, alloc_size, len_defraged);
ret = ocfs2_defrag_extent(context, cpos, phys_cpos,
&alloc_size, flags);
} else {
ret = ocfs2_move_extent(context, cpos, phys_cpos,
&new_phys_cpos, alloc_size,
flags);
new_phys_cpos += alloc_size;
}
if (ret < 0) {
mlog_errno(ret);
goto out;
}
context->clusters_moved += alloc_size;
next:
cpos += alloc_size;
len_to_move -= alloc_size;
}
done:
range->me_flags |= OCFS2_MOVE_EXT_FL_COMPLETE;
out:
range->me_moved_len = ocfs2_clusters_to_bytes(osb->sb,
context->clusters_moved);
range->me_new_offset = ocfs2_clusters_to_bytes(osb->sb,
context->new_phys_cpos);
ocfs2_schedule_truncate_log_flush(osb, 1);
ocfs2_run_deallocs(osb, &context->dealloc);
return ret;
}
static int ocfs2_move_extents(struct ocfs2_move_extents_context *context)
{
int status;
handle_t *handle;
struct inode *inode = context->inode;
struct ocfs2_dinode *di;
struct buffer_head *di_bh = NULL;
struct ocfs2_super *osb = OCFS2_SB(inode->i_sb);
if (!inode)
return -ENOENT;
if (ocfs2_is_hard_readonly(osb) || ocfs2_is_soft_readonly(osb))
return -EROFS;
mutex_lock(&inode->i_mutex);
/*
* This prevents concurrent writes from other nodes
*/
status = ocfs2_rw_lock(inode, 1);
if (status) {
mlog_errno(status);
goto out;
}
status = ocfs2_inode_lock(inode, &di_bh, 1);
if (status) {
mlog_errno(status);
goto out_rw_unlock;
}
/*
* rememer ip_xattr_sem also needs to be held if necessary
*/
down_write(&OCFS2_I(inode)->ip_alloc_sem);
status = __ocfs2_move_extents_range(di_bh, context);
up_write(&OCFS2_I(inode)->ip_alloc_sem);
if (status) {
mlog_errno(status);
goto out_inode_unlock;
}
/*
* We update ctime for these changes
*/
handle = ocfs2_start_trans(osb, OCFS2_INODE_UPDATE_CREDITS);
if (IS_ERR(handle)) {
status = PTR_ERR(handle);
mlog_errno(status);
goto out_inode_unlock;
}
status = ocfs2_journal_access_di(handle, INODE_CACHE(inode), di_bh,
OCFS2_JOURNAL_ACCESS_WRITE);
if (status) {
mlog_errno(status);
goto out_commit;
}
di = (struct ocfs2_dinode *)di_bh->b_data;
inode->i_ctime = CURRENT_TIME;
di->i_ctime = cpu_to_le64(inode->i_ctime.tv_sec);
di->i_ctime_nsec = cpu_to_le32(inode->i_ctime.tv_nsec);
ocfs2_journal_dirty(handle, di_bh);
out_commit:
ocfs2_commit_trans(osb, handle);
out_inode_unlock:
brelse(di_bh);
ocfs2_inode_unlock(inode, 1);
out_rw_unlock:
ocfs2_rw_unlock(inode, 1);
out:
mutex_unlock(&inode->i_mutex);
return status;
}
int ocfs2_ioctl_move_extents(struct file *filp, void __user *argp)
{
int status;
struct inode *inode = filp->f_path.dentry->d_inode;
struct ocfs2_move_extents range;
struct ocfs2_move_extents_context *context = NULL;
status = mnt_want_write_file(filp);
if (status)
return status;
if ((!S_ISREG(inode->i_mode)) || !(filp->f_mode & FMODE_WRITE))
goto out;
if (inode->i_flags & (S_IMMUTABLE|S_APPEND)) {
status = -EPERM;
goto out;
}
context = kzalloc(sizeof(struct ocfs2_move_extents_context), GFP_NOFS);
if (!context) {
status = -ENOMEM;
mlog_errno(status);
goto out;
}
context->inode = inode;
context->file = filp;
if (argp) {
if (copy_from_user(&range, argp, sizeof(range))) {
status = -EFAULT;
goto out;
}
} else {
status = -EINVAL;
goto out;
}
if (range.me_start > i_size_read(inode))
goto out;
if (range.me_start + range.me_len > i_size_read(inode))
range.me_len = i_size_read(inode) - range.me_start;
context->range = &range;
if (range.me_flags & OCFS2_MOVE_EXT_FL_AUTO_DEFRAG) {
context->auto_defrag = 1;
/*
* ok, the default theshold for the defragmentation
* is 1M, since our maximum clustersize was 1M also.
* any thought?
*/
if (!range.me_threshold)
range.me_threshold = 1024 * 1024;
if (range.me_threshold > i_size_read(inode))
range.me_threshold = i_size_read(inode);
if (range.me_flags & OCFS2_MOVE_EXT_FL_PART_DEFRAG)
context->partial = 1;
} else {
/*
* first best-effort attempt to validate and adjust the goal
* (physical address in block), while it can't guarantee later
* operation can succeed all the time since global_bitmap may
* change a bit over time.
*/
status = ocfs2_validate_and_adjust_move_goal(inode, &range);
if (status)
goto out;
}
status = ocfs2_move_extents(context);
if (status)
mlog_errno(status);
out:
/*
* movement/defragmentation may end up being partially completed,
* that's the reason why we need to return userspace the finished
* length and new_offset even if failure happens somewhere.
*/
if (argp) {
if (copy_to_user(argp, &range, sizeof(range)))
status = -EFAULT;
}
kfree(context);
mnt_drop_write_file(filp);
return status;
}
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