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Diffstat (limited to 'fs/jbd2/journal.c')
-rw-r--r--fs/jbd2/journal.c124
1 files changed, 68 insertions, 56 deletions
diff --git a/fs/jbd2/journal.c b/fs/jbd2/journal.c
index 03c4b9214f56..1ebf2393bfb7 100644
--- a/fs/jbd2/journal.c
+++ b/fs/jbd2/journal.c
@@ -220,19 +220,12 @@ loop:
* so we don't sleep
*/
DEFINE_WAIT(wait);
- int should_sleep = 1;
prepare_to_wait(&journal->j_wait_commit, &wait,
TASK_INTERRUPTIBLE);
- if (journal->j_commit_sequence != journal->j_commit_request)
- should_sleep = 0;
transaction = journal->j_running_transaction;
- if (transaction && time_after_eq(jiffies,
- transaction->t_expires))
- should_sleep = 0;
- if (journal->j_flags & JBD2_UNMOUNT)
- should_sleep = 0;
- if (should_sleep) {
+ if (transaction == NULL ||
+ time_before(jiffies, transaction->t_expires)) {
write_unlock(&journal->j_state_lock);
schedule();
write_lock(&journal->j_state_lock);
@@ -316,11 +309,8 @@ static void journal_kill_thread(journal_t *journal)
*
* Return value:
* <0: Error
- * >=0: Finished OK
- *
- * On success:
- * Bit 0 set == escape performed on the data
- * Bit 1 set == buffer copy-out performed (kfree the data after IO)
+ * =0: Finished OK without escape
+ * =1: Finished OK with escape
*/
int jbd2_journal_write_metadata_buffer(transaction_t *transaction,
@@ -328,7 +318,6 @@ int jbd2_journal_write_metadata_buffer(transaction_t *transaction,
struct buffer_head **bh_out,
sector_t blocknr)
{
- int need_copy_out = 0;
int done_copy_out = 0;
int do_escape = 0;
char *mapped_data;
@@ -355,7 +344,6 @@ int jbd2_journal_write_metadata_buffer(transaction_t *transaction,
atomic_set(&new_bh->b_count, 1);
spin_lock(&jh_in->b_state_lock);
-repeat:
/*
* If a new transaction has already done a buffer copy-out, then
* we use that version of the data for the commit.
@@ -365,8 +353,8 @@ repeat:
new_folio = virt_to_folio(jh_in->b_frozen_data);
new_offset = offset_in_folio(new_folio, jh_in->b_frozen_data);
} else {
- new_folio = jh2bh(jh_in)->b_folio;
- new_offset = offset_in_folio(new_folio, jh2bh(jh_in)->b_data);
+ new_folio = bh_in->b_folio;
+ new_offset = offset_in_folio(new_folio, bh_in->b_data);
}
mapped_data = kmap_local_folio(new_folio, new_offset);
@@ -383,54 +371,52 @@ repeat:
/*
* Check for escaping
*/
- if (*((__be32 *)mapped_data) == cpu_to_be32(JBD2_MAGIC_NUMBER)) {
- need_copy_out = 1;
+ if (*((__be32 *)mapped_data) == cpu_to_be32(JBD2_MAGIC_NUMBER))
do_escape = 1;
- }
kunmap_local(mapped_data);
/*
* Do we need to do a data copy?
*/
- if (need_copy_out && !done_copy_out) {
+ if (do_escape && !done_copy_out) {
char *tmp;
spin_unlock(&jh_in->b_state_lock);
tmp = jbd2_alloc(bh_in->b_size, GFP_NOFS);
if (!tmp) {
brelse(new_bh);
+ free_buffer_head(new_bh);
return -ENOMEM;
}
spin_lock(&jh_in->b_state_lock);
if (jh_in->b_frozen_data) {
jbd2_free(tmp, bh_in->b_size);
- goto repeat;
+ goto copy_done;
}
jh_in->b_frozen_data = tmp;
memcpy_from_folio(tmp, new_folio, new_offset, bh_in->b_size);
-
- new_folio = virt_to_folio(tmp);
- new_offset = offset_in_folio(new_folio, tmp);
- done_copy_out = 1;
-
/*
* This isn't strictly necessary, as we're using frozen
* data for the escaping, but it keeps consistency with
* b_frozen_data usage.
*/
jh_in->b_frozen_triggers = jh_in->b_triggers;
+
+copy_done:
+ new_folio = virt_to_folio(jh_in->b_frozen_data);
+ new_offset = offset_in_folio(new_folio, jh_in->b_frozen_data);
+ done_copy_out = 1;
}
/*
* Did we need to do an escaping? Now we've done all the
* copying, we can finally do so.
+ * b_frozen_data is from jbd2_alloc() which always provides an
+ * address from the direct kernels mapping.
*/
- if (do_escape) {
- mapped_data = kmap_local_folio(new_folio, new_offset);
- *((unsigned int *)mapped_data) = 0;
- kunmap_local(mapped_data);
- }
+ if (do_escape)
+ *((unsigned int *)jh_in->b_frozen_data) = 0;
folio_set_bh(new_bh, new_folio, new_offset);
new_bh->b_size = bh_in->b_size;
@@ -454,7 +440,7 @@ repeat:
set_buffer_shadow(bh_in);
spin_unlock(&jh_in->b_state_lock);
- return do_escape | (done_copy_out << 1);
+ return do_escape;
}
/*
@@ -789,17 +775,7 @@ EXPORT_SYMBOL(jbd2_fc_end_commit_fallback);
/* Return 1 when transaction with given tid has already committed. */
int jbd2_transaction_committed(journal_t *journal, tid_t tid)
{
- int ret = 1;
-
- read_lock(&journal->j_state_lock);
- if (journal->j_running_transaction &&
- journal->j_running_transaction->t_tid == tid)
- ret = 0;
- if (journal->j_committing_transaction &&
- journal->j_committing_transaction->t_tid == tid)
- ret = 0;
- read_unlock(&journal->j_state_lock);
- return ret;
+ return tid_geq(READ_ONCE(journal->j_commit_sequence), tid);
}
EXPORT_SYMBOL(jbd2_transaction_committed);
@@ -1451,6 +1427,48 @@ static int journal_revoke_records_per_block(journal_t *journal)
return space / record_size;
}
+static int jbd2_journal_get_max_txn_bufs(journal_t *journal)
+{
+ return (journal->j_total_len - journal->j_fc_wbufsize) / 3;
+}
+
+/*
+ * Base amount of descriptor blocks we reserve for each transaction.
+ */
+static int jbd2_descriptor_blocks_per_trans(journal_t *journal)
+{
+ int tag_space = journal->j_blocksize - sizeof(journal_header_t);
+ int tags_per_block;
+
+ /* Subtract UUID */
+ tag_space -= 16;
+ if (jbd2_journal_has_csum_v2or3(journal))
+ tag_space -= sizeof(struct jbd2_journal_block_tail);
+ /* Commit code leaves a slack space of 16 bytes at the end of block */
+ tags_per_block = (tag_space - 16) / journal_tag_bytes(journal);
+ /*
+ * Revoke descriptors are accounted separately so we need to reserve
+ * space for commit block and normal transaction descriptor blocks.
+ */
+ return 1 + DIV_ROUND_UP(jbd2_journal_get_max_txn_bufs(journal),
+ tags_per_block);
+}
+
+/*
+ * Initialize number of blocks each transaction reserves for its bookkeeping
+ * and maximum number of blocks a transaction can use. This needs to be called
+ * after the journal size and the fastcommit area size are initialized.
+ */
+static void jbd2_journal_init_transaction_limits(journal_t *journal)
+{
+ journal->j_revoke_records_per_block =
+ journal_revoke_records_per_block(journal);
+ journal->j_transaction_overhead_buffers =
+ jbd2_descriptor_blocks_per_trans(journal);
+ journal->j_max_transaction_buffers =
+ jbd2_journal_get_max_txn_bufs(journal);
+}
+
/*
* Load the on-disk journal superblock and read the key fields into the
* journal_t.
@@ -1492,8 +1510,8 @@ static int journal_load_superblock(journal_t *journal)
if (jbd2_journal_has_csum_v2or3(journal))
journal->j_csum_seed = jbd2_chksum(journal, ~0, sb->s_uuid,
sizeof(sb->s_uuid));
- journal->j_revoke_records_per_block =
- journal_revoke_records_per_block(journal);
+ /* After journal features are set, we can compute transaction limits */
+ jbd2_journal_init_transaction_limits(journal);
if (jbd2_has_feature_fast_commit(journal)) {
journal->j_fc_last = be32_to_cpu(sb->s_maxlen);
@@ -1599,7 +1617,6 @@ static journal_t *journal_init_common(struct block_device *bdev,
journal->j_shrinker->scan_objects = jbd2_journal_shrink_scan;
journal->j_shrinker->count_objects = jbd2_journal_shrink_count;
- journal->j_shrinker->batch = journal->j_max_transaction_buffers;
journal->j_shrinker->private_data = journal;
shrinker_register(journal->j_shrinker);
@@ -1743,8 +1760,6 @@ static int journal_reset(journal_t *journal)
journal->j_commit_sequence = journal->j_transaction_sequence - 1;
journal->j_commit_request = journal->j_commit_sequence;
- journal->j_max_transaction_buffers = jbd2_journal_get_max_txn_bufs(journal);
-
/*
* Now that journal recovery is done, turn fast commits off here. This
* way, if fast commit was enabled before the crash but if now FS has
@@ -2285,8 +2300,6 @@ jbd2_journal_initialize_fast_commit(journal_t *journal)
journal->j_fc_first = journal->j_last + 1;
journal->j_fc_off = 0;
journal->j_free = journal->j_last - journal->j_first;
- journal->j_max_transaction_buffers =
- jbd2_journal_get_max_txn_bufs(journal);
return 0;
}
@@ -2374,8 +2387,7 @@ int jbd2_journal_set_features(journal_t *journal, unsigned long compat,
sb->s_feature_ro_compat |= cpu_to_be32(ro);
sb->s_feature_incompat |= cpu_to_be32(incompat);
unlock_buffer(journal->j_sb_buffer);
- journal->j_revoke_records_per_block =
- journal_revoke_records_per_block(journal);
+ jbd2_journal_init_transaction_limits(journal);
return 1;
#undef COMPAT_FEATURE_ON
@@ -2406,8 +2418,7 @@ void jbd2_journal_clear_features(journal_t *journal, unsigned long compat,
sb->s_feature_compat &= ~cpu_to_be32(compat);
sb->s_feature_ro_compat &= ~cpu_to_be32(ro);
sb->s_feature_incompat &= ~cpu_to_be32(incompat);
- journal->j_revoke_records_per_block =
- journal_revoke_records_per_block(journal);
+ jbd2_journal_init_transaction_limits(journal);
}
EXPORT_SYMBOL(jbd2_journal_clear_features);
@@ -3181,6 +3192,7 @@ static void __exit journal_exit(void)
jbd2_journal_destroy_caches();
}
+MODULE_DESCRIPTION("Generic filesystem journal-writing module");
MODULE_LICENSE("GPL");
module_init(journal_init);
module_exit(journal_exit);