static void account_shadow(void *_shadow, unsigned long _sb, u64 ignore,
size_t ignore2)
{
struct logfs_shadow *shadow = _shadow;
struct super_block *sb = (void *)_sb;
struct logfs_super *super = logfs_super(sb);
super->s_free_bytes -= shadow->new_len;
super->s_used_bytes += shadow->new_len;
super->s_dirty_used_bytes -= shadow->new_len;
super->s_free_bytes += shadow->old_len;
super->s_used_bytes -= shadow->old_len;
super->s_dirty_free_bytes -= shadow->old_len;
logfs_set_segment_used(sb, shadow->old_ofs, -shadow->old_len);
logfs_set_segment_used(sb, shadow->new_ofs, shadow->new_len);
log_journal("account_shadow(%llx, %llx, %x) %llx->%llx %x->%x\n",
shadow->ino, shadow->bix, shadow->gc_level,
shadow->old_ofs, shadow->new_ofs,
shadow->old_len, shadow->new_len);
mempool_free(shadow, super->s_shadow_pool);
}
void do_logfs_journal_wl_pass(struct super_block *sb)
{
struct logfs_super *super = logfs_super(sb);
struct logfs_area *area = super->s_journal_area;
u32 segno, ec;
int i, err;
log_journal("Journal requires wear-leveling.\n");
/* Drop old segments */
journal_for_each(i)
if (super->s_journal_seg[i]) {
logfs_set_segment_unreserved(sb,
super->s_journal_seg[i],
super->s_journal_ec[i]);
super->s_journal_seg[i] = 0;
super->s_journal_ec[i] = 0;
}
/* Get new segments */
for (i = 0; i < super->s_no_journal_segs; i++) {
segno = get_best_cand(sb, &super->s_reserve_list, &ec);
super->s_journal_seg[i] = segno;
super->s_journal_ec[i] = ec;
logfs_set_segment_reserved(sb, segno);
}
/* Manually move journal_area */
area->a_segno = super->s_journal_seg[0];
area->a_is_open = 0;
area->a_used_bytes = 0;
/* Write journal */
logfs_write_anchor(sb);
/* Write superblocks */
err = logfs_write_sb(sb);
BUG_ON(err);
}
void do_logfs_journal_wl_pass(struct super_block *sb)
{
struct logfs_super *super = logfs_super(sb);
struct logfs_area *area = super->s_journal_area;
struct btree_head32 *head = &super->s_reserved_segments;
u32 segno, ec;
int i, err;
log_journal("Journal requires wear-leveling.\n");
/* Drop old segments */
journal_for_each(i)
if (super->s_journal_seg[i]) {
btree_remove32(head, super->s_journal_seg[i]);
logfs_set_segment_unreserved(sb,
super->s_journal_seg[i],
super->s_journal_ec[i]);
super->s_journal_seg[i] = 0;
super->s_journal_ec[i] = 0;
}
/* Get new segments */
for (i = 0; i < super->s_no_journal_segs; i++) {
segno = get_best_cand(sb, &super->s_reserve_list, &ec);
super->s_journal_seg[i] = segno;
super->s_journal_ec[i] = ec;
logfs_set_segment_reserved(sb, segno);
<<<<<<< HEAD
err = btree_insert32(head, segno, (void *)1, GFP_NOFS);
=======
static int logfs_read_segment(struct super_block *sb, u32 segno)
{
struct logfs_super *super = logfs_super(sb);
struct logfs_journal_header *jh = super->s_compressed_je;
u64 ofs, seg_ofs = dev_ofs(sb, segno, 0);
u32 h_ofs, last_ofs = 0;
u16 len, datalen, last_len = 0;
int i, err;
for (h_ofs = 0; h_ofs < super->s_segsize; h_ofs += sizeof(*jh)) {
ofs = seg_ofs + h_ofs;
err = __read_je_header(sb, ofs, jh);
if (err)
continue;
if (jh->h_type != cpu_to_be16(JE_COMMIT))
continue;
err = __read_je_payload(sb, ofs, jh);
if (err)
continue;
len = be16_to_cpu(jh->h_len);
datalen = be16_to_cpu(jh->h_datalen);
if ((datalen > sizeof(super->s_je_array)) ||
(datalen % sizeof(__be64)))
continue;
last_ofs = h_ofs;
last_len = datalen;
h_ofs += ALIGN(len, sizeof(*jh)) - sizeof(*jh);
}
if (last_ofs == 0)
return -ENOENT;
ofs = seg_ofs + last_ofs;
log_journal("Read commit from %llx\n", ofs);
err = __read_je(sb, ofs, jh);
BUG_ON(err);
if (err)
return err;
unpack(jh, super->s_je_array);
super->s_no_je = last_len / sizeof(__be64);
for (i = 0; i < super->s_no_je; i++) {
err = read_je(sb, be64_to_cpu(super->s_je_array[i]));
if (err)
return err;
}
super->s_journal_area->a_segno = segno;
return 0;
}
static int logfs_write_obj_aliases(struct super_block *sb)
{
struct logfs_super *super = logfs_super(sb);
int err;
log_journal("logfs_write_obj_aliases: %d aliases to write\n",
super->s_no_object_aliases);
super->s_je_fill = 0;
err = logfs_write_obj_aliases_pagecache(sb);
if (err)
return err;
if (super->s_je_fill)
err = logfs_write_je_buf(sb, super->s_je, JE_OBJ_ALIAS,
super->s_je_fill
* sizeof(struct logfs_obj_alias));
return err;
}
void do_logfs_journal_wl_pass(struct super_block *sb)
{
struct logfs_super *super = logfs_super(sb);
struct logfs_area *area = super->s_journal_area;
struct btree_head32 *head = &super->s_reserved_segments;
u32 segno, ec;
int i, err;
log_journal("Journal requires wear-leveling.\n");
journal_for_each(i)
if (super->s_journal_seg[i]) {
btree_remove32(head, super->s_journal_seg[i]);
logfs_set_segment_unreserved(sb,
super->s_journal_seg[i],
super->s_journal_ec[i]);
super->s_journal_seg[i] = 0;
super->s_journal_ec[i] = 0;
}
for (i = 0; i < super->s_no_journal_segs; i++) {
segno = get_best_cand(sb, &super->s_reserve_list, &ec);
super->s_journal_seg[i] = segno;
super->s_journal_ec[i] = ec;
logfs_set_segment_reserved(sb, segno);
err = btree_insert32(head, segno, (void *)1, GFP_NOFS);
BUG_ON(err);
err = logfs_erase_segment(sb, segno, 1);
BUG_ON(err);
}
freeseg(sb, area->a_segno);
area->a_segno = super->s_journal_seg[0];
area->a_is_open = 0;
area->a_used_bytes = 0;
logfs_write_anchor(sb);
err = logfs_write_sb(sb);
BUG_ON(err);
}
void do_logfs_journal_wl_pass(struct super_block *sb)
{
struct logfs_super *super = logfs_super(sb);
struct logfs_area *area = super->s_journal_area;
struct btree_head32 *head = &super->s_reserved_segments;
u32 segno, ec;
int i, err;
log_journal("Journal requires wear-leveling.\n");
/* Drop old segments */
journal_for_each(i)
if (super->s_journal_seg[i]) {
btree_remove32(head, super->s_journal_seg[i]);
logfs_set_segment_unreserved(sb,
super->s_journal_seg[i],
super->s_journal_ec[i]);
super->s_journal_seg[i] = 0;
super->s_journal_ec[i] = 0;
}
/* Get new segments */
for (i = 0; i < super->s_no_journal_segs; i++) {
segno = get_best_cand(sb, &super->s_reserve_list, &ec);
super->s_journal_seg[i] = segno;
super->s_journal_ec[i] = ec;
logfs_set_segment_reserved(sb, segno);
err = btree_insert32(head, segno, (void *)1, GFP_KERNEL);
BUG_ON(err); /* mempool should prevent this */
err = logfs_erase_segment(sb, segno, 1);
BUG_ON(err); /* FIXME: remount-ro would be nicer */
}
/* Manually move journal_area */
freeseg(sb, area->a_segno);
area->a_segno = super->s_journal_seg[0];
area->a_is_open = 0;
area->a_used_bytes = 0;
/* Write journal */
logfs_write_anchor(sb);
/* Write superblocks */
err = logfs_write_sb(sb);
BUG_ON(err);
}
static void journal_get_free_segment(struct logfs_area *area)
{
struct logfs_super *super = logfs_super(area->a_sb);
int i;
journal_for_each(i) {
if (area->a_segno != super->s_journal_seg[i])
continue;
do {
i++;
if (i == LOGFS_JOURNAL_SEGS)
i = 0;
} while (!super->s_journal_seg[i]);
area->a_segno = super->s_journal_seg[i];
area->a_erase_count = ++(super->s_journal_ec[i]);
log_journal("Journal now at %x (ec %x)\n", area->a_segno,
area->a_erase_count);
return;
}
BUG();
}
/*
* Write all journal entries. The goto logic ensures that all journal entries
* are written whenever a new segment is used. It is ugly and potentially a
* bit wasteful, but robustness is more important. With this we can *always*
* erase all journal segments except the one containing the most recent commit.
*/
void logfs_write_anchor(struct super_block *sb)
{
struct logfs_super *super = logfs_super(sb);
struct logfs_area *area = super->s_journal_area;
int i, err;
if (!(super->s_flags & LOGFS_SB_FLAG_DIRTY))
return;
super->s_flags &= ~LOGFS_SB_FLAG_DIRTY;
BUG_ON(super->s_flags & LOGFS_SB_FLAG_SHUTDOWN);
mutex_lock(&super->s_journal_mutex);
logfs_sync_segments(sb);
account_shadows(sb);
again:
super->s_no_je = 0;
for_each_area(i) {
if (!super->s_area[i]->a_is_open)
continue;
super->s_sum_index = i;
err = logfs_write_je(sb, logfs_write_area);
if (err)
goto again;
}
err = logfs_write_obj_aliases(sb);
if (err)
goto again;
err = logfs_write_je(sb, logfs_write_erasecount);
if (err)
goto again;
err = logfs_write_je(sb, __logfs_write_anchor);
if (err)
goto again;
err = logfs_write_je(sb, logfs_write_dynsb);
if (err)
goto again;
/*
* Order is imperative. First we sync all writes, including the
* non-committed journal writes. Then we write the final commit and
* sync the current journal segment.
* There is a theoretical bug here. Syncing the journal segment will
* write a number of journal entries and the final commit. All these
* are written in a single operation. If the device layer writes the
* data back-to-front, the commit will precede the other journal
* entries, leaving a race window.
* Two fixes are possible. Preferred is to fix the device layer to
* ensure writes happen front-to-back. Alternatively we can insert
* another logfs_sync_area() super->s_devops->sync() combo before
* writing the commit.
*/
super->s_devops->sync(sb);
err = logfs_write_je(sb, logfs_write_commit);
if (err)
goto again;
log_journal("Write commit to %llx\n",
be64_to_cpu(super->s_je_array[super->s_no_je - 1]));
logfs_sync_area(area);
BUG_ON(area->a_used_bytes != area->a_written_bytes);
super->s_devops->sync(sb);
mutex_unlock(&super->s_journal_mutex);
return;
}
