#include <linux/proc_fs.h>
#include <linux/debugfs.h>
#include <linux/seq_file.h>
+#include <linux/math64.h>
+#include <linux/hash.h>
+#include <linux/log2.h>
+#include <linux/vmalloc.h>
+
+#define CREATE_TRACE_POINTS
+#include <trace/events/jbd2.h>
#include <asm/uaccess.h>
#include <asm/page.h>
-#include <asm/div64.h>
EXPORT_SYMBOL(jbd2_journal_start);
EXPORT_SYMBOL(jbd2_journal_restart);
EXPORT_SYMBOL(jbd2_journal_get_write_access);
EXPORT_SYMBOL(jbd2_journal_get_create_access);
EXPORT_SYMBOL(jbd2_journal_get_undo_access);
+EXPORT_SYMBOL(jbd2_journal_set_triggers);
EXPORT_SYMBOL(jbd2_journal_dirty_metadata);
EXPORT_SYMBOL(jbd2_journal_release_buffer);
EXPORT_SYMBOL(jbd2_journal_forget);
EXPORT_SYMBOL(jbd2_journal_check_used_features);
EXPORT_SYMBOL(jbd2_journal_check_available_features);
EXPORT_SYMBOL(jbd2_journal_set_features);
-EXPORT_SYMBOL(jbd2_journal_create);
EXPORT_SYMBOL(jbd2_journal_load);
EXPORT_SYMBOL(jbd2_journal_destroy);
EXPORT_SYMBOL(jbd2_journal_abort);
EXPORT_SYMBOL(jbd2_journal_ack_err);
EXPORT_SYMBOL(jbd2_journal_clear_err);
EXPORT_SYMBOL(jbd2_log_wait_commit);
+EXPORT_SYMBOL(jbd2_log_start_commit);
EXPORT_SYMBOL(jbd2_journal_start_commit);
EXPORT_SYMBOL(jbd2_journal_force_commit_nested);
EXPORT_SYMBOL(jbd2_journal_wipe);
static int journal_convert_superblock_v1(journal_t *, journal_superblock_t *);
static void __journal_abort_soft (journal_t *journal, int errno);
+static int jbd2_journal_create_slab(size_t slab_size);
/*
* Helper function used to manage commit timeouts
journal->j_task = current;
wake_up(&journal->j_wait_done_commit);
- printk(KERN_INFO "kjournald2 starting. Commit interval %ld seconds\n",
- journal->j_commit_interval / HZ);
-
/*
* And now, wait forever for commit wakeup events.
*/
{
struct task_struct *t;
- t = kthread_run(kjournald2, journal, "kjournald2");
+ t = kthread_run(kjournald2, journal, "jbd2/%s",
+ journal->j_devname);
if (IS_ERR(t))
return PTR_ERR(t);
struct page *new_page;
unsigned int new_offset;
struct buffer_head *bh_in = jh2bh(jh_in);
+ struct jbd2_buffer_trigger_type *triggers;
+ journal_t *journal = transaction->t_journal;
/*
* The buffer really shouldn't be locked: only the current committing
J_ASSERT_BH(bh_in, buffer_jbddirty(bh_in));
new_bh = alloc_buffer_head(GFP_NOFS|__GFP_NOFAIL);
+ /* keep subsequent assertions sane */
+ new_bh->b_state = 0;
+ init_buffer(new_bh, NULL, NULL);
+ atomic_set(&new_bh->b_count, 1);
+ new_jh = jbd2_journal_add_journal_head(new_bh); /* This sleeps */
/*
* If a new transaction has already done a buffer copy-out, then
done_copy_out = 1;
new_page = virt_to_page(jh_in->b_frozen_data);
new_offset = offset_in_page(jh_in->b_frozen_data);
+ triggers = jh_in->b_frozen_triggers;
} else {
new_page = jh2bh(jh_in)->b_page;
new_offset = offset_in_page(jh2bh(jh_in)->b_data);
+ triggers = jh_in->b_triggers;
}
mapped_data = kmap_atomic(new_page, KM_USER0);
/*
+ * Fire any commit trigger. Do this before checking for escaping,
+ * as the trigger may modify the magic offset. If a copy-out
+ * happens afterwards, it will have the correct data in the buffer.
+ */
+ jbd2_buffer_commit_trigger(jh_in, mapped_data + new_offset,
+ triggers);
+
+ /*
* Check for escaping
*/
if (*((__be32 *)(mapped_data + new_offset)) ==
jbd_unlock_bh_state(bh_in);
tmp = jbd2_alloc(bh_in->b_size, GFP_NOFS);
+ if (!tmp) {
+ jbd2_journal_put_journal_head(new_jh);
+ return -ENOMEM;
+ }
jbd_lock_bh_state(bh_in);
if (jh_in->b_frozen_data) {
jbd2_free(tmp, bh_in->b_size);
new_page = virt_to_page(tmp);
new_offset = offset_in_page(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;
}
/*
kunmap_atomic(mapped_data, KM_USER0);
}
- /* keep subsequent assertions sane */
- new_bh->b_state = 0;
- init_buffer(new_bh, NULL, NULL);
- atomic_set(&new_bh->b_count, 1);
- jbd_unlock_bh_state(bh_in);
-
- new_jh = jbd2_journal_add_journal_head(new_bh); /* This sleeps */
-
set_bh_page(new_bh, new_page, new_offset);
new_jh->b_transaction = NULL;
new_bh->b_size = jh2bh(jh_in)->b_size;
* copying is moved to the transaction's shadow queue.
*/
JBUFFER_TRACE(jh_in, "file as BJ_Shadow");
- jbd2_journal_file_buffer(jh_in, transaction, BJ_Shadow);
+ spin_lock(&journal->j_list_lock);
+ __jbd2_journal_file_buffer(jh_in, transaction, BJ_Shadow);
+ spin_unlock(&journal->j_list_lock);
+ jbd_unlock_bh_state(bh_in);
+
JBUFFER_TRACE(new_jh, "file as BJ_IO");
jbd2_journal_file_buffer(new_jh, transaction, BJ_IO);
}
/*
- * Called under j_state_lock. Returns true if a transaction was started.
+ * Called under j_state_lock. Returns true if a transaction commit was started.
*/
int __jbd2_log_start_commit(journal_t *journal, tid_t target)
{
/*
* Start a commit of the current running transaction (if any). Returns true
- * if a transaction was started, and fills its tid in at *ptid
+ * if a transaction is going to be committed (or is currently already
+ * committing), and fills its tid in at *ptid
*/
int jbd2_journal_start_commit(journal_t *journal, tid_t *ptid)
{
if (journal->j_running_transaction) {
tid_t tid = journal->j_running_transaction->t_tid;
- ret = __jbd2_log_start_commit(journal, tid);
- if (ret && ptid)
+ __jbd2_log_start_commit(journal, tid);
+ /* There's a running transaction and we've just made sure
+ * it's commit has been scheduled. */
+ if (ptid)
*ptid = tid;
- } else if (journal->j_committing_transaction && ptid) {
+ ret = 1;
+ } else if (journal->j_committing_transaction) {
/*
* If ext3_write_super() recently started a commit, then we
* have to wait for completion of that transaction
*/
- *ptid = journal->j_committing_transaction->t_tid;
+ if (ptid)
+ *ptid = journal->j_committing_transaction->t_tid;
ret = 1;
}
spin_unlock(&journal->j_state_lock);
return NULL;
bh = __getblk(journal->j_dev, blocknr, journal->j_blocksize);
+ if (!bh)
+ return NULL;
lock_buffer(bh);
memset(bh->b_data, 0, journal->j_blocksize);
set_buffer_uptodate(bh);
int max;
};
-static void *jbd2_history_skip_empty(struct jbd2_stats_proc_session *s,
- struct transaction_stats_s *ts,
- int first)
-{
- if (ts == s->stats + s->max)
- ts = s->stats;
- if (!first && ts == s->stats + s->start)
- return NULL;
- while (ts->ts_type == 0) {
- ts++;
- if (ts == s->stats + s->max)
- ts = s->stats;
- if (ts == s->stats + s->start)
- return NULL;
- }
- return ts;
-
-}
-
-static void *jbd2_seq_history_start(struct seq_file *seq, loff_t *pos)
-{
- struct jbd2_stats_proc_session *s = seq->private;
- struct transaction_stats_s *ts;
- int l = *pos;
-
- if (l == 0)
- return SEQ_START_TOKEN;
- ts = jbd2_history_skip_empty(s, s->stats + s->start, 1);
- if (!ts)
- return NULL;
- l--;
- while (l) {
- ts = jbd2_history_skip_empty(s, ++ts, 0);
- if (!ts)
- break;
- l--;
- }
- return ts;
-}
-
-static void *jbd2_seq_history_next(struct seq_file *seq, void *v, loff_t *pos)
-{
- struct jbd2_stats_proc_session *s = seq->private;
- struct transaction_stats_s *ts = v;
-
- ++*pos;
- if (v == SEQ_START_TOKEN)
- return jbd2_history_skip_empty(s, s->stats + s->start, 1);
- else
- return jbd2_history_skip_empty(s, ++ts, 0);
-}
-
-static int jbd2_seq_history_show(struct seq_file *seq, void *v)
-{
- struct transaction_stats_s *ts = v;
- if (v == SEQ_START_TOKEN) {
- seq_printf(seq, "%-4s %-5s %-5s %-5s %-5s %-5s %-5s %-6s %-5s "
- "%-5s %-5s %-5s %-5s %-5s\n", "R/C", "tid",
- "wait", "run", "lock", "flush", "log", "hndls",
- "block", "inlog", "ctime", "write", "drop",
- "close");
- return 0;
- }
- if (ts->ts_type == JBD2_STATS_RUN)
- seq_printf(seq, "%-4s %-5lu %-5u %-5u %-5u %-5u %-5u "
- "%-6lu %-5lu %-5lu\n", "R", ts->ts_tid,
- jiffies_to_msecs(ts->u.run.rs_wait),
- jiffies_to_msecs(ts->u.run.rs_running),
- jiffies_to_msecs(ts->u.run.rs_locked),
- jiffies_to_msecs(ts->u.run.rs_flushing),
- jiffies_to_msecs(ts->u.run.rs_logging),
- ts->u.run.rs_handle_count,
- ts->u.run.rs_blocks,
- ts->u.run.rs_blocks_logged);
- else if (ts->ts_type == JBD2_STATS_CHECKPOINT)
- seq_printf(seq, "%-4s %-5lu %48s %-5u %-5lu %-5lu %-5lu\n",
- "C", ts->ts_tid, " ",
- jiffies_to_msecs(ts->u.chp.cs_chp_time),
- ts->u.chp.cs_written, ts->u.chp.cs_dropped,
- ts->u.chp.cs_forced_to_close);
- else
- J_ASSERT(0);
- return 0;
-}
-
-static void jbd2_seq_history_stop(struct seq_file *seq, void *v)
-{
-}
-
-static struct seq_operations jbd2_seq_history_ops = {
- .start = jbd2_seq_history_start,
- .next = jbd2_seq_history_next,
- .stop = jbd2_seq_history_stop,
- .show = jbd2_seq_history_show,
-};
-
-static int jbd2_seq_history_open(struct inode *inode, struct file *file)
-{
- journal_t *journal = PDE(inode)->data;
- struct jbd2_stats_proc_session *s;
- int rc, size;
-
- s = kmalloc(sizeof(*s), GFP_KERNEL);
- if (s == NULL)
- return -ENOMEM;
- size = sizeof(struct transaction_stats_s) * journal->j_history_max;
- s->stats = kmalloc(size, GFP_KERNEL);
- if (s->stats == NULL) {
- kfree(s);
- return -ENOMEM;
- }
- spin_lock(&journal->j_history_lock);
- memcpy(s->stats, journal->j_history, size);
- s->max = journal->j_history_max;
- s->start = journal->j_history_cur % s->max;
- spin_unlock(&journal->j_history_lock);
-
- rc = seq_open(file, &jbd2_seq_history_ops);
- if (rc == 0) {
- struct seq_file *m = file->private_data;
- m->private = s;
- } else {
- kfree(s->stats);
- kfree(s);
- }
- return rc;
-
-}
-
-static int jbd2_seq_history_release(struct inode *inode, struct file *file)
-{
- struct seq_file *seq = file->private_data;
- struct jbd2_stats_proc_session *s = seq->private;
-
- kfree(s->stats);
- kfree(s);
- return seq_release(inode, file);
-}
-
-static struct file_operations jbd2_seq_history_fops = {
- .owner = THIS_MODULE,
- .open = jbd2_seq_history_open,
- .read = seq_read,
- .llseek = seq_lseek,
- .release = jbd2_seq_history_release,
-};
-
static void *jbd2_seq_info_start(struct seq_file *seq, loff_t *pos)
{
return *pos ? NULL : SEQ_START_TOKEN;
if (v != SEQ_START_TOKEN)
return 0;
- seq_printf(seq, "%lu transaction, each upto %u blocks\n",
+ seq_printf(seq, "%lu transaction, each up to %u blocks\n",
s->stats->ts_tid,
s->journal->j_max_transaction_buffers);
if (s->stats->ts_tid == 0)
return 0;
seq_printf(seq, "average: \n %ums waiting for transaction\n",
- jiffies_to_msecs(s->stats->u.run.rs_wait / s->stats->ts_tid));
+ jiffies_to_msecs(s->stats->run.rs_wait / s->stats->ts_tid));
seq_printf(seq, " %ums running transaction\n",
- jiffies_to_msecs(s->stats->u.run.rs_running / s->stats->ts_tid));
+ jiffies_to_msecs(s->stats->run.rs_running / s->stats->ts_tid));
seq_printf(seq, " %ums transaction was being locked\n",
- jiffies_to_msecs(s->stats->u.run.rs_locked / s->stats->ts_tid));
+ jiffies_to_msecs(s->stats->run.rs_locked / s->stats->ts_tid));
seq_printf(seq, " %ums flushing data (in ordered mode)\n",
- jiffies_to_msecs(s->stats->u.run.rs_flushing / s->stats->ts_tid));
+ jiffies_to_msecs(s->stats->run.rs_flushing / s->stats->ts_tid));
seq_printf(seq, " %ums logging transaction\n",
- jiffies_to_msecs(s->stats->u.run.rs_logging / s->stats->ts_tid));
- seq_printf(seq, " %luus average transaction commit time\n",
- do_div(s->journal->j_average_commit_time, 1000));
+ jiffies_to_msecs(s->stats->run.rs_logging / s->stats->ts_tid));
+ seq_printf(seq, " %lluus average transaction commit time\n",
+ div_u64(s->journal->j_average_commit_time, 1000));
seq_printf(seq, " %lu handles per transaction\n",
- s->stats->u.run.rs_handle_count / s->stats->ts_tid);
+ s->stats->run.rs_handle_count / s->stats->ts_tid);
seq_printf(seq, " %lu blocks per transaction\n",
- s->stats->u.run.rs_blocks / s->stats->ts_tid);
+ s->stats->run.rs_blocks / s->stats->ts_tid);
seq_printf(seq, " %lu logged blocks per transaction\n",
- s->stats->u.run.rs_blocks_logged / s->stats->ts_tid);
+ s->stats->run.rs_blocks_logged / s->stats->ts_tid);
return 0;
}
{
}
-static struct seq_operations jbd2_seq_info_ops = {
+static const struct seq_operations jbd2_seq_info_ops = {
.start = jbd2_seq_info_start,
.next = jbd2_seq_info_next,
.stop = jbd2_seq_info_stop,
return seq_release(inode, file);
}
-static struct file_operations jbd2_seq_info_fops = {
+static const struct file_operations jbd2_seq_info_fops = {
.owner = THIS_MODULE,
.open = jbd2_seq_info_open,
.read = seq_read,
{
journal->j_proc_entry = proc_mkdir(journal->j_devname, proc_jbd2_stats);
if (journal->j_proc_entry) {
- proc_create_data("history", S_IRUGO, journal->j_proc_entry,
- &jbd2_seq_history_fops, journal);
proc_create_data("info", S_IRUGO, journal->j_proc_entry,
&jbd2_seq_info_fops, journal);
}
static void jbd2_stats_proc_exit(journal_t *journal)
{
remove_proc_entry("info", journal->j_proc_entry);
- remove_proc_entry("history", journal->j_proc_entry);
remove_proc_entry(journal->j_devname, proc_jbd2_stats);
}
-static void journal_init_stats(journal_t *journal)
-{
- int size;
-
- if (!proc_jbd2_stats)
- return;
-
- journal->j_history_max = 100;
- size = sizeof(struct transaction_stats_s) * journal->j_history_max;
- journal->j_history = kzalloc(size, GFP_KERNEL);
- if (!journal->j_history) {
- journal->j_history_max = 0;
- return;
- }
- spin_lock_init(&journal->j_history_lock);
-}
-
/*
* Management for journal control blocks: functions to create and
* destroy journal_t structures, and to initialise and read existing
journal_t *journal;
int err;
- journal = kzalloc(sizeof(*journal), GFP_KERNEL|__GFP_NOFAIL);
+ journal = kzalloc(sizeof(*journal), GFP_KERNEL);
if (!journal)
goto fail;
spin_lock_init(&journal->j_state_lock);
journal->j_commit_interval = (HZ * JBD2_DEFAULT_MAX_COMMIT_AGE);
+ journal->j_min_batch_time = 0;
+ journal->j_max_batch_time = 15000; /* 15ms */
/* The journal is marked for error until we succeed with recovery! */
journal->j_flags = JBD2_ABORT;
goto fail;
}
- journal_init_stats(journal);
+ spin_lock_init(&journal->j_history_lock);
return journal;
fail:
/* journal descriptor can store up to n blocks -bzzz */
journal->j_blocksize = blocksize;
+ jbd2_stats_proc_init(journal);
n = journal->j_blocksize / sizeof(journal_block_tag_t);
journal->j_wbufsize = n;
journal->j_wbuf = kmalloc(n * sizeof(struct buffer_head*), GFP_KERNEL);
if (!journal->j_wbuf) {
printk(KERN_ERR "%s: Cant allocate bhs for commit thread\n",
__func__);
- kfree(journal);
- journal = NULL;
- goto out;
+ goto out_err;
}
journal->j_dev = bdev;
journal->j_fs_dev = fs_dev;
p = journal->j_devname;
while ((p = strchr(p, '/')))
*p = '!';
- jbd2_stats_proc_init(journal);
bh = __getblk(journal->j_dev, start, journal->j_blocksize);
- J_ASSERT(bh != NULL);
+ if (!bh) {
+ printk(KERN_ERR
+ "%s: Cannot get buffer for journal superblock\n",
+ __func__);
+ goto out_err;
+ }
journal->j_sb_buffer = bh;
journal->j_superblock = (journal_superblock_t *)bh->b_data;
-out:
+
return journal;
+out_err:
+ kfree(journal->j_wbuf);
+ jbd2_stats_proc_exit(journal);
+ kfree(journal);
+ return NULL;
}
/**
while ((p = strchr(p, '/')))
*p = '!';
p = journal->j_devname + strlen(journal->j_devname);
- sprintf(p, ":%lu", journal->j_inode->i_ino);
+ sprintf(p, "-%lu", journal->j_inode->i_ino);
jbd_debug(1,
"journal %p: inode %s/%ld, size %Ld, bits %d, blksize %ld\n",
journal, inode->i_sb->s_id, inode->i_ino,
if (!journal->j_wbuf) {
printk(KERN_ERR "%s: Cant allocate bhs for commit thread\n",
__func__);
- jbd2_stats_proc_exit(journal);
- kfree(journal);
- return NULL;
+ goto out_err;
}
err = jbd2_journal_bmap(journal, 0, &blocknr);
if (err) {
printk(KERN_ERR "%s: Cannnot locate journal superblock\n",
__func__);
- jbd2_stats_proc_exit(journal);
- kfree(journal);
- return NULL;
+ goto out_err;
}
bh = __getblk(journal->j_dev, blocknr, journal->j_blocksize);
- J_ASSERT(bh != NULL);
+ if (!bh) {
+ printk(KERN_ERR
+ "%s: Cannot get buffer for journal superblock\n",
+ __func__);
+ goto out_err;
+ }
journal->j_sb_buffer = bh;
journal->j_superblock = (journal_superblock_t *)bh->b_data;
return journal;
+out_err:
+ kfree(journal->j_wbuf);
+ jbd2_stats_proc_exit(journal);
+ kfree(journal);
+ return NULL;
}
/*
first = be32_to_cpu(sb->s_first);
last = be32_to_cpu(sb->s_maxlen);
+ if (first + JBD2_MIN_JOURNAL_BLOCKS > last + 1) {
+ printk(KERN_ERR "JBD: Journal too short (blocks %llu-%llu).\n",
+ first, last);
+ journal_fail_superblock(journal);
+ return -EINVAL;
+ }
journal->j_first = first;
journal->j_last = last;
}
/**
- * int jbd2_journal_create() - Initialise the new journal file
- * @journal: Journal to create. This structure must have been initialised
- *
- * Given a journal_t structure which tells us which disk blocks we can
- * use, create a new journal superblock and initialise all of the
- * journal fields from scratch.
- **/
-int jbd2_journal_create(journal_t *journal)
-{
- unsigned long long blocknr;
- struct buffer_head *bh;
- journal_superblock_t *sb;
- int i, err;
-
- if (journal->j_maxlen < JBD2_MIN_JOURNAL_BLOCKS) {
- printk (KERN_ERR "Journal length (%d blocks) too short.\n",
- journal->j_maxlen);
- journal_fail_superblock(journal);
- return -EINVAL;
- }
-
- if (journal->j_inode == NULL) {
- /*
- * We don't know what block to start at!
- */
- printk(KERN_EMERG
- "%s: creation of journal on external device!\n",
- __func__);
- BUG();
- }
-
- /* Zero out the entire journal on disk. We cannot afford to
- have any blocks on disk beginning with JBD2_MAGIC_NUMBER. */
- jbd_debug(1, "JBD: Zeroing out journal blocks...\n");
- for (i = 0; i < journal->j_maxlen; i++) {
- err = jbd2_journal_bmap(journal, i, &blocknr);
- if (err)
- return err;
- bh = __getblk(journal->j_dev, blocknr, journal->j_blocksize);
- lock_buffer(bh);
- memset (bh->b_data, 0, journal->j_blocksize);
- BUFFER_TRACE(bh, "marking dirty");
- mark_buffer_dirty(bh);
- BUFFER_TRACE(bh, "marking uptodate");
- set_buffer_uptodate(bh);
- unlock_buffer(bh);
- __brelse(bh);
- }
-
- sync_blockdev(journal->j_dev);
- jbd_debug(1, "JBD: journal cleared.\n");
-
- /* OK, fill in the initial static fields in the new superblock */
- sb = journal->j_superblock;
-
- sb->s_header.h_magic = cpu_to_be32(JBD2_MAGIC_NUMBER);
- sb->s_header.h_blocktype = cpu_to_be32(JBD2_SUPERBLOCK_V2);
-
- sb->s_blocksize = cpu_to_be32(journal->j_blocksize);
- sb->s_maxlen = cpu_to_be32(journal->j_maxlen);
- sb->s_first = cpu_to_be32(1);
-
- journal->j_transaction_sequence = 1;
-
- journal->j_flags &= ~JBD2_ABORT;
- journal->j_format_version = 2;
-
- return journal_reset(journal);
-}
-
-/**
* void jbd2_journal_update_superblock() - Update journal sb on disk.
* @journal: The journal to update.
* @wait: Set to '0' if you don't want to wait for IO completion.
}
}
+ /*
+ * Create a slab for this blocksize
+ */
+ err = jbd2_journal_create_slab(be32_to_cpu(sb->s_blocksize));
+ if (err)
+ return err;
+
/* Let the recovery code check whether it needs to recover any
* data from the journal. */
if (jbd2_journal_recover(journal))
goto recovery_error;
+ if (journal->j_failed_commit) {
+ printk(KERN_ERR "JBD2: journal transaction %u on %s "
+ "is corrupt.\n", journal->j_failed_commit,
+ journal->j_devname);
+ return -EIO;
+ }
+
/* OK, we've finished with the dynamic journal bits:
* reinitialise the dynamic contents of the superblock in memory
* and reset them on disk. */
spin_lock(&journal->j_list_lock);
while (journal->j_checkpoint_transactions != NULL) {
spin_unlock(&journal->j_list_lock);
+ mutex_lock(&journal->j_checkpoint_mutex);
jbd2_log_do_checkpoint(journal);
+ mutex_unlock(&journal->j_checkpoint_mutex);
spin_lock(&journal->j_list_lock);
}
* Journal abort has very specific semantics, which we describe
* for journal abort.
*
- * Two internal function, which provide abort to te jbd layer
+ * Two internal functions, which provide abort to the jbd layer
* itself are here.
*/
* int jbd2_journal_errno () - returns the journal's error state.
* @journal: journal to examine.
*
- * This is the errno numbet set with jbd2_journal_abort(), the last
+ * This is the errno number set with jbd2_journal_abort(), the last
* time the journal was mounted - if the journal was stopped
* without calling abort this will be 0.
*
* int jbd2_journal_clear_err () - clears the journal's error state
* @journal: journal to act on.
*
- * An error must be cleared or Acked to take a FS out of readonly
+ * An error must be cleared or acked to take a FS out of readonly
* mode.
*/
int jbd2_journal_clear_err(journal_t *journal)
* void jbd2_journal_ack_err() - Ack journal err.
* @journal: journal to act on.
*
- * An error must be cleared or Acked to take a FS out of readonly
+ * An error must be cleared or acked to take a FS out of readonly
* mode.
*/
void jbd2_journal_ack_err(journal_t *journal)
}
/*
+ * JBD memory management
+ *
+ * These functions are used to allocate block-sized chunks of memory
+ * used for making copies of buffer_head data. Very often it will be
+ * page-sized chunks of data, but sometimes it will be in
+ * sub-page-size chunks. (For example, 16k pages on Power systems
+ * with a 4k block file system.) For blocks smaller than a page, we
+ * use a SLAB allocator. There are slab caches for each block size,
+ * which are allocated at mount time, if necessary, and we only free
+ * (all of) the slab caches when/if the jbd2 module is unloaded. For
+ * this reason we don't need to a mutex to protect access to
+ * jbd2_slab[] allocating or releasing memory; only in
+ * jbd2_journal_create_slab().
+ */
+#define JBD2_MAX_SLABS 8
+static struct kmem_cache *jbd2_slab[JBD2_MAX_SLABS];
+static DECLARE_MUTEX(jbd2_slab_create_sem);
+
+static const char *jbd2_slab_names[JBD2_MAX_SLABS] = {
+ "jbd2_1k", "jbd2_2k", "jbd2_4k", "jbd2_8k",
+ "jbd2_16k", "jbd2_32k", "jbd2_64k", "jbd2_128k"
+};
+
+
+static void jbd2_journal_destroy_slabs(void)
+{
+ int i;
+
+ for (i = 0; i < JBD2_MAX_SLABS; i++) {
+ if (jbd2_slab[i])
+ kmem_cache_destroy(jbd2_slab[i]);
+ jbd2_slab[i] = NULL;
+ }
+}
+
+static int jbd2_journal_create_slab(size_t size)
+{
+ int i = order_base_2(size) - 10;
+ size_t slab_size;
+
+ if (size == PAGE_SIZE)
+ return 0;
+
+ if (i >= JBD2_MAX_SLABS)
+ return -EINVAL;
+
+ if (unlikely(i < 0))
+ i = 0;
+ down(&jbd2_slab_create_sem);
+ if (jbd2_slab[i]) {
+ up(&jbd2_slab_create_sem);
+ return 0; /* Already created */
+ }
+
+ slab_size = 1 << (i+10);
+ jbd2_slab[i] = kmem_cache_create(jbd2_slab_names[i], slab_size,
+ slab_size, 0, NULL);
+ up(&jbd2_slab_create_sem);
+ if (!jbd2_slab[i]) {
+ printk(KERN_EMERG "JBD2: no memory for jbd2_slab cache\n");
+ return -ENOMEM;
+ }
+ return 0;
+}
+
+static struct kmem_cache *get_slab(size_t size)
+{
+ int i = order_base_2(size) - 10;
+
+ BUG_ON(i >= JBD2_MAX_SLABS);
+ if (unlikely(i < 0))
+ i = 0;
+ BUG_ON(jbd2_slab[i] == NULL);
+ return jbd2_slab[i];
+}
+
+void *jbd2_alloc(size_t size, gfp_t flags)
+{
+ void *ptr;
+
+ BUG_ON(size & (size-1)); /* Must be a power of 2 */
+
+ flags |= __GFP_REPEAT;
+ if (size == PAGE_SIZE)
+ ptr = (void *)__get_free_pages(flags, 0);
+ else if (size > PAGE_SIZE) {
+ int order = get_order(size);
+
+ if (order < 3)
+ ptr = (void *)__get_free_pages(flags, order);
+ else
+ ptr = vmalloc(size);
+ } else
+ ptr = kmem_cache_alloc(get_slab(size), flags);
+
+ /* Check alignment; SLUB has gotten this wrong in the past,
+ * and this can lead to user data corruption! */
+ BUG_ON(((unsigned long) ptr) & (size-1));
+
+ return ptr;
+}
+
+void jbd2_free(void *ptr, size_t size)
+{
+ if (size == PAGE_SIZE) {
+ free_pages((unsigned long)ptr, 0);
+ return;
+ }
+ if (size > PAGE_SIZE) {
+ int order = get_order(size);
+
+ if (order < 3)
+ free_pages((unsigned long)ptr, order);
+ else
+ vfree(ptr);
+ return;
+ }
+ kmem_cache_free(get_slab(size), ptr);
+};
+
+/*
* Journal_head storage management
*/
static struct kmem_cache *jbd2_journal_head_cache;
{
jbd2_debugfs_dir = debugfs_create_dir("jbd2", NULL);
if (jbd2_debugfs_dir)
- jbd2_debug = debugfs_create_u8(JBD2_DEBUG_NAME, S_IRUGO,
+ jbd2_debug = debugfs_create_u8(JBD2_DEBUG_NAME,
+ S_IRUGO | S_IWUSR,
jbd2_debugfs_dir,
&jbd2_journal_enable_debug);
}
jbd2_journal_destroy_revoke_caches();
jbd2_journal_destroy_jbd2_journal_head_cache();
jbd2_journal_destroy_handle_cache();
+ jbd2_journal_destroy_slabs();
}
static int __init journal_init(void)
jbd2_journal_destroy_caches();
}
+/*
+ * jbd2_dev_to_name is a utility function used by the jbd2 and ext4
+ * tracing infrastructure to map a dev_t to a device name.
+ *
+ * The caller should use rcu_read_lock() in order to make sure the
+ * device name stays valid until its done with it. We use
+ * rcu_read_lock() as well to make sure we're safe in case the caller
+ * gets sloppy, and because rcu_read_lock() is cheap and can be safely
+ * nested.
+ */
+struct devname_cache {
+ struct rcu_head rcu;
+ dev_t device;
+ char devname[BDEVNAME_SIZE];
+};
+#define CACHE_SIZE_BITS 6
+static struct devname_cache *devcache[1 << CACHE_SIZE_BITS];
+static DEFINE_SPINLOCK(devname_cache_lock);
+
+static void free_devcache(struct rcu_head *rcu)
+{
+ kfree(rcu);
+}
+
+const char *jbd2_dev_to_name(dev_t device)
+{
+ int i = hash_32(device, CACHE_SIZE_BITS);
+ char *ret;
+ struct block_device *bd;
+ static struct devname_cache *new_dev;
+
+ rcu_read_lock();
+ if (devcache[i] && devcache[i]->device == device) {
+ ret = devcache[i]->devname;
+ rcu_read_unlock();
+ return ret;
+ }
+ rcu_read_unlock();
+
+ new_dev = kmalloc(sizeof(struct devname_cache), GFP_KERNEL);
+ if (!new_dev)
+ return "NODEV-ALLOCFAILURE"; /* Something non-NULL */
+ spin_lock(&devname_cache_lock);
+ if (devcache[i]) {
+ if (devcache[i]->device == device) {
+ kfree(new_dev);
+ ret = devcache[i]->devname;
+ spin_unlock(&devname_cache_lock);
+ return ret;
+ }
+ call_rcu(&devcache[i]->rcu, free_devcache);
+ }
+ devcache[i] = new_dev;
+ devcache[i]->device = device;
+ bd = bdget(device);
+ if (bd) {
+ bdevname(bd, devcache[i]->devname);
+ bdput(bd);
+ } else
+ __bdevname(device, devcache[i]->devname);
+ ret = devcache[i]->devname;
+ spin_unlock(&devname_cache_lock);
+ return ret;
+}
+EXPORT_SYMBOL(jbd2_dev_to_name);
+
MODULE_LICENSE("GPL");
module_init(journal_init);
module_exit(journal_exit);