[PATCH v4 12/27] jbd2: fix kernel-doc markups

From: Mauro Carvalho Chehab
Date: Mon Nov 16 2020 - 05:19:06 EST


Kernel-doc markup should use this format:
identifier - description

They should not have any type before that, as otherwise
the parser won't do the right thing.

Also, some identifiers have different names between their
prototypes and the kernel-doc markup.

Reviewed-by: Jan Kara <jack@xxxxxxx>
Signed-off-by: Mauro Carvalho Chehab <mchehab+huawei@xxxxxxxxxx>
---
fs/jbd2/journal.c | 34 ++++++++++++++++++----------------
fs/jbd2/transaction.c | 31 ++++++++++++++++---------------
include/linux/jbd2.h | 2 +-
3 files changed, 35 insertions(+), 32 deletions(-)

diff --git a/fs/jbd2/journal.c b/fs/jbd2/journal.c
index 0c3d5e3b24b2..188f79d76988 100644
--- a/fs/jbd2/journal.c
+++ b/fs/jbd2/journal.c
@@ -549,57 +549,59 @@ static int __jbd2_journal_force_commit(journal_t *journal)
} else if (journal->j_committing_transaction)
transaction = journal->j_committing_transaction;

if (!transaction) {
/* Nothing to commit */
read_unlock(&journal->j_state_lock);
return 0;
}
tid = transaction->t_tid;
read_unlock(&journal->j_state_lock);
if (need_to_start)
jbd2_log_start_commit(journal, tid);
ret = jbd2_log_wait_commit(journal, tid);
if (!ret)
ret = 1;

return ret;
}

/**
- * Force and wait upon a commit if the calling process is not within
- * transaction. This is used for forcing out undo-protected data which contains
- * bitmaps, when the fs is running out of space.
+ * jbd2_journal_force_commit_nested - Force and wait upon a commit if the
+ * calling process is not within transaction.
*
* @journal: journal to force
* Returns true if progress was made.
+ *
+ * This is used for forcing out undo-protected data which contains
+ * bitmaps, when the fs is running out of space.
*/
int jbd2_journal_force_commit_nested(journal_t *journal)
{
int ret;

ret = __jbd2_journal_force_commit(journal);
return ret > 0;
}

/**
- * int journal_force_commit() - force any uncommitted transactions
+ * jbd2_journal_force_commit() - force any uncommitted transactions
* @journal: journal to force
*
* Caller want unconditional commit. We can only force the running transaction
* if we don't have an active handle, otherwise, we will deadlock.
*/
int jbd2_journal_force_commit(journal_t *journal)
{
int ret;

J_ASSERT(!current->journal_info);
ret = __jbd2_journal_force_commit(journal);
if (ret > 0)
ret = 0;
return ret;
}

/*
* Start a commit of the current running transaction (if any). Returns true
* if a transaction is going to be committed (or is currently already
* committing), and fills its tid in at *ptid
@@ -1864,41 +1866,41 @@ static int load_superblock(journal_t *journal)
journal->j_first = be32_to_cpu(sb->s_first);
journal->j_errno = be32_to_cpu(sb->s_errno);
journal->j_last = be32_to_cpu(sb->s_maxlen);

if (jbd2_has_feature_fast_commit(journal)) {
journal->j_fc_last = be32_to_cpu(sb->s_maxlen);
num_fc_blocks = be32_to_cpu(sb->s_num_fc_blks);
if (!num_fc_blocks)
num_fc_blocks = JBD2_MIN_FC_BLOCKS;
if (journal->j_last - num_fc_blocks >= JBD2_MIN_JOURNAL_BLOCKS)
journal->j_last = journal->j_fc_last - num_fc_blocks;
journal->j_fc_first = journal->j_last + 1;
journal->j_fc_off = 0;
}

return 0;
}


/**
- * int jbd2_journal_load() - Read journal from disk.
+ * jbd2_journal_load() - Read journal from disk.
* @journal: Journal to act on.
*
* Given a journal_t structure which tells us which disk blocks contain
* a journal, read the journal from disk to initialise the in-memory
* structures.
*/
int jbd2_journal_load(journal_t *journal)
{
int err;
journal_superblock_t *sb;

err = load_superblock(journal);
if (err)
return err;

sb = journal->j_superblock;
/* If this is a V2 superblock, then we have to check the
* features flags on it. */

if (journal->j_format_version >= 2) {
@@ -1934,41 +1936,41 @@ int jbd2_journal_load(journal_t *journal)
* clear JBD2_ABORT flag initialized in journal_init_common
* here to update log tail information with the newest seq.
*/
journal->j_flags &= ~JBD2_ABORT;

/* OK, we've finished with the dynamic journal bits:
* reinitialise the dynamic contents of the superblock in memory
* and reset them on disk. */
if (journal_reset(journal))
goto recovery_error;

journal->j_flags |= JBD2_LOADED;
return 0;

recovery_error:
printk(KERN_WARNING "JBD2: recovery failed\n");
return -EIO;
}

/**
- * void jbd2_journal_destroy() - Release a journal_t structure.
+ * jbd2_journal_destroy() - Release a journal_t structure.
* @journal: Journal to act on.
*
* Release a journal_t structure once it is no longer in use by the
* journaled object.
* Return <0 if we couldn't clean up the journal.
*/
int jbd2_journal_destroy(journal_t *journal)
{
int err = 0;

/* Wait for the commit thread to wake up and die. */
journal_kill_thread(journal);

/* Force a final log commit */
if (journal->j_running_transaction)
jbd2_journal_commit_transaction(journal);

/* Force any old transactions to disk */

/* Totally anal locking here... */
@@ -2011,76 +2013,76 @@ int jbd2_journal_destroy(journal_t *journal)
err = -EIO;
brelse(journal->j_sb_buffer);
}

if (journal->j_proc_entry)
jbd2_stats_proc_exit(journal);
iput(journal->j_inode);
if (journal->j_revoke)
jbd2_journal_destroy_revoke(journal);
if (journal->j_chksum_driver)
crypto_free_shash(journal->j_chksum_driver);
kfree(journal->j_fc_wbuf);
kfree(journal->j_wbuf);
kfree(journal);

return err;
}


/**
- *int jbd2_journal_check_used_features() - Check if features specified are used.
+ * jbd2_journal_check_used_features() - Check if features specified are used.
* @journal: Journal to check.
* @compat: bitmask of compatible features
* @ro: bitmask of features that force read-only mount
* @incompat: bitmask of incompatible features
*
* Check whether the journal uses all of a given set of
* features. Return true (non-zero) if it does.
**/

int jbd2_journal_check_used_features(journal_t *journal, unsigned long compat,
unsigned long ro, unsigned long incompat)
{
journal_superblock_t *sb;

if (!compat && !ro && !incompat)
return 1;
/* Load journal superblock if it is not loaded yet. */
if (journal->j_format_version == 0 &&
journal_get_superblock(journal) != 0)
return 0;
if (journal->j_format_version == 1)
return 0;

sb = journal->j_superblock;

if (((be32_to_cpu(sb->s_feature_compat) & compat) == compat) &&
((be32_to_cpu(sb->s_feature_ro_compat) & ro) == ro) &&
((be32_to_cpu(sb->s_feature_incompat) & incompat) == incompat))
return 1;

return 0;
}

/**
- * int jbd2_journal_check_available_features() - Check feature set in journalling layer
+ * jbd2_journal_check_available_features() - Check feature set in journalling layer
* @journal: Journal to check.
* @compat: bitmask of compatible features
* @ro: bitmask of features that force read-only mount
* @incompat: bitmask of incompatible features
*
* Check whether the journaling code supports the use of
* all of a given set of features on this journal. Return true
* (non-zero) if it can. */

int jbd2_journal_check_available_features(journal_t *journal, unsigned long compat,
unsigned long ro, unsigned long incompat)
{
if (!compat && !ro && !incompat)
return 1;

/* We can support any known requested features iff the
* superblock is in version 2. Otherwise we fail to support any
* extended sb features. */

if (journal->j_format_version != 2)
@@ -2109,41 +2111,41 @@ jbd2_journal_initialize_fast_commit(journal_t *journal)
/* Are we called twice? */
WARN_ON(journal->j_fc_wbuf != NULL);
journal->j_fc_wbuf = kmalloc_array(num_fc_blks,
sizeof(struct buffer_head *), GFP_KERNEL);
if (!journal->j_fc_wbuf)
return -ENOMEM;

journal->j_fc_wbufsize = num_fc_blks;
journal->j_fc_last = journal->j_last;
journal->j_last = journal->j_fc_last - num_fc_blks;
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;
}

/**
- * int jbd2_journal_set_features() - Mark a given journal feature in the superblock
+ * jbd2_journal_set_features() - Mark a given journal feature in the superblock
* @journal: Journal to act on.
* @compat: bitmask of compatible features
* @ro: bitmask of features that force read-only mount
* @incompat: bitmask of incompatible features
*
* Mark a given journal feature as present on the
* superblock. Returns true if the requested features could be set.
*
*/

int jbd2_journal_set_features(journal_t *journal, unsigned long compat,
unsigned long ro, unsigned long incompat)
{
#define INCOMPAT_FEATURE_ON(f) \
((incompat & (f)) && !(sb->s_feature_incompat & cpu_to_be32(f)))
#define COMPAT_FEATURE_ON(f) \
((compat & (f)) && !(sb->s_feature_compat & cpu_to_be32(f)))
journal_superblock_t *sb;

if (jbd2_journal_check_used_features(journal, compat, ro, incompat))
@@ -2200,70 +2202,70 @@ int jbd2_journal_set_features(journal_t *journal, unsigned long compat,

/* If enabling v1 checksums, downgrade superblock */
if (COMPAT_FEATURE_ON(JBD2_FEATURE_COMPAT_CHECKSUM))
sb->s_feature_incompat &=
~cpu_to_be32(JBD2_FEATURE_INCOMPAT_CSUM_V2 |
JBD2_FEATURE_INCOMPAT_CSUM_V3);

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);
unlock_buffer(journal->j_sb_buffer);
journal->j_revoke_records_per_block =
journal_revoke_records_per_block(journal);

return 1;
#undef COMPAT_FEATURE_ON
#undef INCOMPAT_FEATURE_ON
}

/*
- * jbd2_journal_clear_features () - Clear a given journal feature in the
+ * jbd2_journal_clear_features() - Clear a given journal feature in the
* superblock
* @journal: Journal to act on.
* @compat: bitmask of compatible features
* @ro: bitmask of features that force read-only mount
* @incompat: bitmask of incompatible features
*
* Clear a given journal feature as present on the
* superblock.
*/
void jbd2_journal_clear_features(journal_t *journal, unsigned long compat,
unsigned long ro, unsigned long incompat)
{
journal_superblock_t *sb;

jbd_debug(1, "Clear features 0x%lx/0x%lx/0x%lx\n",
compat, ro, incompat);

sb = journal->j_superblock;

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);
}
EXPORT_SYMBOL(jbd2_journal_clear_features);

/**
- * int jbd2_journal_flush () - Flush journal
+ * jbd2_journal_flush() - Flush journal
* @journal: Journal to act on.
*
* Flush all data for a given journal to disk and empty the journal.
* Filesystems can use this when remounting readonly to ensure that
* recovery does not need to happen on remount.
*/

int jbd2_journal_flush(journal_t *journal)
{
int err = 0;
transaction_t *transaction = NULL;

write_lock(&journal->j_state_lock);

/* Force everything buffered to the log... */
if (journal->j_running_transaction) {
transaction = journal->j_running_transaction;
__jbd2_log_start_commit(journal, transaction->t_tid);
} else if (journal->j_committing_transaction)
transaction = journal->j_committing_transaction;
@@ -2304,82 +2306,82 @@ int jbd2_journal_flush(journal_t *journal)

/* Finally, mark the journal as really needing no recovery.
* This sets s_start==0 in the underlying superblock, which is
* the magic code for a fully-recovered superblock. Any future
* commits of data to the journal will restore the current
* s_start value. */
jbd2_mark_journal_empty(journal, REQ_SYNC | REQ_FUA);
mutex_unlock(&journal->j_checkpoint_mutex);
write_lock(&journal->j_state_lock);
J_ASSERT(!journal->j_running_transaction);
J_ASSERT(!journal->j_committing_transaction);
J_ASSERT(!journal->j_checkpoint_transactions);
J_ASSERT(journal->j_head == journal->j_tail);
J_ASSERT(journal->j_tail_sequence == journal->j_transaction_sequence);
write_unlock(&journal->j_state_lock);
out:
return err;
}

/**
- * int jbd2_journal_wipe() - Wipe journal contents
+ * jbd2_journal_wipe() - Wipe journal contents
* @journal: Journal to act on.
* @write: flag (see below)
*
* Wipe out all of the contents of a journal, safely. This will produce
* a warning if the journal contains any valid recovery information.
* Must be called between journal_init_*() and jbd2_journal_load().
*
* If 'write' is non-zero, then we wipe out the journal on disk; otherwise
* we merely suppress recovery.
*/

int jbd2_journal_wipe(journal_t *journal, int write)
{
int err = 0;

J_ASSERT (!(journal->j_flags & JBD2_LOADED));

err = load_superblock(journal);
if (err)
return err;

if (!journal->j_tail)
goto no_recovery;

printk(KERN_WARNING "JBD2: %s recovery information on journal\n",
write ? "Clearing" : "Ignoring");

err = jbd2_journal_skip_recovery(journal);
if (write) {
/* Lock to make assertions happy... */
mutex_lock_io(&journal->j_checkpoint_mutex);
jbd2_mark_journal_empty(journal, REQ_SYNC | REQ_FUA);
mutex_unlock(&journal->j_checkpoint_mutex);
}

no_recovery:
return err;
}

/**
- * void jbd2_journal_abort () - Shutdown the journal immediately.
+ * jbd2_journal_abort () - Shutdown the journal immediately.
* @journal: the journal to shutdown.
* @errno: an error number to record in the journal indicating
* the reason for the shutdown.
*
* Perform a complete, immediate shutdown of the ENTIRE
* journal (not of a single transaction). This operation cannot be
* undone without closing and reopening the journal.
*
* The jbd2_journal_abort function is intended to support higher level error
* recovery mechanisms such as the ext2/ext3 remount-readonly error
* mode.
*
* Journal abort has very specific semantics. Any existing dirty,
* unjournaled buffers in the main filesystem will still be written to
* disk by bdflush, but the journaling mechanism will be suspended
* immediately and no further transaction commits will be honoured.
*
* Any dirty, journaled buffers will be written back to disk without
* hitting the journal. Atomicity cannot be guaranteed on an aborted
* filesystem, but we _do_ attempt to leave as much data as possible
@@ -2436,85 +2438,85 @@ void jbd2_journal_abort(journal_t *journal, int errno)
* to release all journaled buffer.
*/
pr_err("Aborting journal on device %s.\n", journal->j_devname);

journal->j_flags |= JBD2_ABORT;
journal->j_errno = errno;
transaction = journal->j_running_transaction;
if (transaction)
__jbd2_log_start_commit(journal, transaction->t_tid);
write_unlock(&journal->j_state_lock);

/*
* Record errno to the journal super block, so that fsck and jbd2
* layer could realise that a filesystem check is needed.
*/
jbd2_journal_update_sb_errno(journal);
mutex_unlock(&journal->j_abort_mutex);
}

/**
- * int jbd2_journal_errno () - returns the journal's error state.
+ * jbd2_journal_errno() - returns the journal's error state.
* @journal: journal to examine.
*
* 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.
*
* If the journal has been aborted on this mount time -EROFS will
* be returned.
*/
int jbd2_journal_errno(journal_t *journal)
{
int err;

read_lock(&journal->j_state_lock);
if (journal->j_flags & JBD2_ABORT)
err = -EROFS;
else
err = journal->j_errno;
read_unlock(&journal->j_state_lock);
return err;
}

/**
- * int jbd2_journal_clear_err () - clears the journal's error state
+ * 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
* mode.
*/
int jbd2_journal_clear_err(journal_t *journal)
{
int err = 0;

write_lock(&journal->j_state_lock);
if (journal->j_flags & JBD2_ABORT)
err = -EROFS;
else
journal->j_errno = 0;
write_unlock(&journal->j_state_lock);
return err;
}

/**
- * void jbd2_journal_ack_err() - Ack journal err.
+ * 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
* mode.
*/
void jbd2_journal_ack_err(journal_t *journal)
{
write_lock(&journal->j_state_lock);
if (journal->j_errno)
journal->j_flags |= JBD2_ACK_ERR;
write_unlock(&journal->j_state_lock);
}

int jbd2_journal_blocks_per_page(struct inode *inode)
{
return 1 << (PAGE_SHIFT - inode->i_sb->s_blocksize_bits);
}

/*
* helper functions to deal with 32 or 64bit block numbers.
diff --git a/fs/jbd2/transaction.c b/fs/jbd2/transaction.c
index d54f04674e8e..9396666b7314 100644
--- a/fs/jbd2/transaction.c
+++ b/fs/jbd2/transaction.c
@@ -502,41 +502,41 @@ handle_t *jbd2__journal_start(journal_t *journal, int nblocks, int rsv_blocks,

err = start_this_handle(journal, handle, gfp_mask);
if (err < 0) {
if (handle->h_rsv_handle)
jbd2_free_handle(handle->h_rsv_handle);
jbd2_free_handle(handle);
return ERR_PTR(err);
}
handle->h_type = type;
handle->h_line_no = line_no;
trace_jbd2_handle_start(journal->j_fs_dev->bd_dev,
handle->h_transaction->t_tid, type,
line_no, nblocks);

return handle;
}
EXPORT_SYMBOL(jbd2__journal_start);


/**
- * handle_t *jbd2_journal_start() - Obtain a new handle.
+ * jbd2_journal_start() - Obtain a new handle.
* @journal: Journal to start transaction on.
* @nblocks: number of block buffer we might modify
*
* We make sure that the transaction can guarantee at least nblocks of
* modified buffers in the log. We block until the log can guarantee
* that much space. Additionally, if rsv_blocks > 0, we also create another
* handle with rsv_blocks reserved blocks in the journal. This handle is
* stored in h_rsv_handle. It is not attached to any particular transaction
* and thus doesn't block transaction commit. If the caller uses this reserved
* handle, it has to set h_rsv_handle to NULL as otherwise jbd2_journal_stop()
* on the parent handle will dispose the reserved one. Reserved handle has to
* be converted to a normal handle using jbd2_journal_start_reserved() before
* it can be used.
*
* Return a pointer to a newly allocated handle, or an ERR_PTR() value
* on failure.
*/
handle_t *jbd2_journal_start(journal_t *journal, int nblocks)
{
return jbd2__journal_start(journal, nblocks, 0, 0, GFP_NOFS, 0, 0);
@@ -549,41 +549,41 @@ static void __jbd2_journal_unreserve_handle(handle_t *handle, transaction_t *t)

WARN_ON(!handle->h_reserved);
sub_reserved_credits(journal, handle->h_total_credits);
if (t)
atomic_sub(handle->h_total_credits, &t->t_outstanding_credits);
}

void jbd2_journal_free_reserved(handle_t *handle)
{
journal_t *journal = handle->h_journal;

/* Get j_state_lock to pin running transaction if it exists */
read_lock(&journal->j_state_lock);
__jbd2_journal_unreserve_handle(handle, journal->j_running_transaction);
read_unlock(&journal->j_state_lock);
jbd2_free_handle(handle);
}
EXPORT_SYMBOL(jbd2_journal_free_reserved);

/**
- * int jbd2_journal_start_reserved() - start reserved handle
+ * jbd2_journal_start_reserved() - start reserved handle
* @handle: handle to start
* @type: for handle statistics
* @line_no: for handle statistics
*
* Start handle that has been previously reserved with jbd2_journal_reserve().
* This attaches @handle to the running transaction (or creates one if there's
* not transaction running). Unlike jbd2_journal_start() this function cannot
* block on journal commit, checkpointing, or similar stuff. It can block on
* memory allocation or frozen journal though.
*
* Return 0 on success, non-zero on error - handle is freed in that case.
*/
int jbd2_journal_start_reserved(handle_t *handle, unsigned int type,
unsigned int line_no)
{
journal_t *journal = handle->h_journal;
int ret = -EIO;

if (WARN_ON(!handle->h_reserved)) {
/* Someone passed in normal handle? Just stop it. */
@@ -603,41 +603,41 @@ int jbd2_journal_start_reserved(handle_t *handle, unsigned int type,
/*
* GFP_NOFS is here because callers are likely from writeback or
* similarly constrained call sites
*/
ret = start_this_handle(journal, handle, GFP_NOFS);
if (ret < 0) {
handle->h_journal = journal;
jbd2_journal_free_reserved(handle);
return ret;
}
handle->h_type = type;
handle->h_line_no = line_no;
trace_jbd2_handle_start(journal->j_fs_dev->bd_dev,
handle->h_transaction->t_tid, type,
line_no, handle->h_total_credits);
return 0;
}
EXPORT_SYMBOL(jbd2_journal_start_reserved);

/**
- * int jbd2_journal_extend() - extend buffer credits.
+ * jbd2_journal_extend() - extend buffer credits.
* @handle: handle to 'extend'
* @nblocks: nr blocks to try to extend by.
* @revoke_records: number of revoke records to try to extend by.
*
* Some transactions, such as large extends and truncates, can be done
* atomically all at once or in several stages. The operation requests
* a credit for a number of buffer modifications in advance, but can
* extend its credit if it needs more.
*
* jbd2_journal_extend tries to give the running handle more buffer credits.
* It does not guarantee that allocation - this is a best-effort only.
* The calling process MUST be able to deal cleanly with a failure to
* extend here.
*
* Return 0 on success, non-zero on failure.
*
* return code < 0 implies an error
* return code > 0 implies normal transaction-full status.
*/
int jbd2_journal_extend(handle_t *handle, int nblocks, int revoke_records)
@@ -728,41 +728,41 @@ static void stop_this_handle(handle_t *handle)
DIV_ROUND_UP(t_revokes - revokes, rr_per_blk);
handle->h_total_credits -= revoke_descriptors;
}
atomic_sub(handle->h_total_credits,
&transaction->t_outstanding_credits);
if (handle->h_rsv_handle)
__jbd2_journal_unreserve_handle(handle->h_rsv_handle,
transaction);
if (atomic_dec_and_test(&transaction->t_updates))
wake_up(&journal->j_wait_updates);

rwsem_release(&journal->j_trans_commit_map, _THIS_IP_);
/*
* Scope of the GFP_NOFS context is over here and so we can restore the
* original alloc context.
*/
memalloc_nofs_restore(handle->saved_alloc_context);
}

/**
- * int jbd2_journal_restart() - restart a handle .
+ * jbd2__journal_restart() - restart a handle .
* @handle: handle to restart
* @nblocks: nr credits requested
* @revoke_records: number of revoke record credits requested
* @gfp_mask: memory allocation flags (for start_this_handle)
*
* Restart a handle for a multi-transaction filesystem
* operation.
*
* If the jbd2_journal_extend() call above fails to grant new buffer credits
* to a running handle, a call to jbd2_journal_restart will commit the
* handle's transaction so far and reattach the handle to a new
* transaction capable of guaranteeing the requested number of
* credits. We preserve reserved handle if there's any attached to the
* passed in handle.
*/
int jbd2__journal_restart(handle_t *handle, int nblocks, int revoke_records,
gfp_t gfp_mask)
{
transaction_t *transaction = handle->h_transaction;
journal_t *journal;
@@ -798,41 +798,41 @@ int jbd2__journal_restart(handle_t *handle, int nblocks, int revoke_records,
DIV_ROUND_UP(revoke_records,
journal->j_revoke_records_per_block);
handle->h_revoke_credits = revoke_records;
ret = start_this_handle(journal, handle, gfp_mask);
trace_jbd2_handle_restart(journal->j_fs_dev->bd_dev,
ret ? 0 : handle->h_transaction->t_tid,
handle->h_type, handle->h_line_no,
handle->h_total_credits);
return ret;
}
EXPORT_SYMBOL(jbd2__journal_restart);


int jbd2_journal_restart(handle_t *handle, int nblocks)
{
return jbd2__journal_restart(handle, nblocks, 0, GFP_NOFS);
}
EXPORT_SYMBOL(jbd2_journal_restart);

/**
- * void jbd2_journal_lock_updates () - establish a transaction barrier.
+ * jbd2_journal_lock_updates () - establish a transaction barrier.
* @journal: Journal to establish a barrier on.
*
* This locks out any further updates from being started, and blocks
* until all existing updates have completed, returning only once the
* journal is in a quiescent state with no updates running.
*
* The journal lock should not be held on entry.
*/
void jbd2_journal_lock_updates(journal_t *journal)
{
DEFINE_WAIT(wait);

jbd2_might_wait_for_commit(journal);

write_lock(&journal->j_state_lock);
++journal->j_barrier_count;

/* Wait until there are no reserved handles */
if (atomic_read(&journal->j_reserved_credits)) {
write_unlock(&journal->j_state_lock);
@@ -857,41 +857,41 @@ void jbd2_journal_lock_updates(journal_t *journal)
break;
}
spin_unlock(&transaction->t_handle_lock);
write_unlock(&journal->j_state_lock);
schedule();
finish_wait(&journal->j_wait_updates, &wait);
write_lock(&journal->j_state_lock);
}
write_unlock(&journal->j_state_lock);

/*
* We have now established a barrier against other normal updates, but
* we also need to barrier against other jbd2_journal_lock_updates() calls
* to make sure that we serialise special journal-locked operations
* too.
*/
mutex_lock(&journal->j_barrier);
}

/**
- * void jbd2_journal_unlock_updates (journal_t* journal) - release barrier
+ * jbd2_journal_unlock_updates () - release barrier
* @journal: Journal to release the barrier on.
*
* Release a transaction barrier obtained with jbd2_journal_lock_updates().
*
* Should be called without the journal lock held.
*/
void jbd2_journal_unlock_updates (journal_t *journal)
{
J_ASSERT(journal->j_barrier_count != 0);

mutex_unlock(&journal->j_barrier);
write_lock(&journal->j_state_lock);
--journal->j_barrier_count;
write_unlock(&journal->j_state_lock);
wake_up(&journal->j_wait_transaction_locked);
}

static void warn_dirty_buffer(struct buffer_head *bh)
{
printk(KERN_WARNING
@@ -1165,41 +1165,42 @@ static bool jbd2_write_access_granted(handle_t *handle, struct buffer_head *bh,
goto out;
/*
* There are two reasons for the barrier here:
* 1) Make sure to fetch b_bh after we did previous checks so that we
* detect when jh went through free, realloc, attach to transaction
* while we were checking. Paired with implicit barrier in that path.
* 2) So that access to bh done after jbd2_write_access_granted()
* doesn't get reordered and see inconsistent state of concurrent
* do_get_write_access().
*/
smp_mb();
if (unlikely(jh->b_bh != bh))
goto out;
ret = true;
out:
rcu_read_unlock();
return ret;
}

/**
- * int jbd2_journal_get_write_access() - notify intent to modify a buffer for metadata (not data) update.
+ * jbd2_journal_get_write_access() - notify intent to modify a buffer
+ * for metadata (not data) update.
* @handle: transaction to add buffer modifications to
* @bh: bh to be used for metadata writes
*
* Returns: error code or 0 on success.
*
* In full data journalling mode the buffer may be of type BJ_AsyncData,
* because we're ``write()ing`` a buffer which is also part of a shared mapping.
*/

int jbd2_journal_get_write_access(handle_t *handle, struct buffer_head *bh)
{
struct journal_head *jh;
int rc;

if (is_handle_aborted(handle))
return -EROFS;

if (jbd2_write_access_granted(handle, bh, false))
return 0;

@@ -1209,41 +1210,41 @@ int jbd2_journal_get_write_access(handle_t *handle, struct buffer_head *bh)
* completes any outstanding IO before proceeding. */
rc = do_get_write_access(handle, jh, 0);
jbd2_journal_put_journal_head(jh);
return rc;
}


/*
* When the user wants to journal a newly created buffer_head
* (ie. getblk() returned a new buffer and we are going to populate it
* manually rather than reading off disk), then we need to keep the
* buffer_head locked until it has been completely filled with new
* data. In this case, we should be able to make the assertion that
* the bh is not already part of an existing transaction.
*
* The buffer should already be locked by the caller by this point.
* There is no lock ranking violation: it was a newly created,
* unlocked buffer beforehand. */

/**
- * int jbd2_journal_get_create_access () - notify intent to use newly created bh
+ * jbd2_journal_get_create_access () - notify intent to use newly created bh
* @handle: transaction to new buffer to
* @bh: new buffer.
*
* Call this if you create a new bh.
*/
int jbd2_journal_get_create_access(handle_t *handle, struct buffer_head *bh)
{
transaction_t *transaction = handle->h_transaction;
journal_t *journal;
struct journal_head *jh = jbd2_journal_add_journal_head(bh);
int err;

jbd_debug(5, "journal_head %p\n", jh);
err = -EROFS;
if (is_handle_aborted(handle))
goto out;
journal = transaction->t_journal;
err = 0;

JBUFFER_TRACE(jh, "entry");
@@ -1289,41 +1290,41 @@ int jbd2_journal_get_create_access(handle_t *handle, struct buffer_head *bh)
jh->b_next_transaction = transaction;
spin_unlock(&journal->j_list_lock);
}
spin_unlock(&jh->b_state_lock);

/*
* akpm: I added this. ext3_alloc_branch can pick up new indirect
* blocks which contain freed but then revoked metadata. We need
* to cancel the revoke in case we end up freeing it yet again
* and the reallocating as data - this would cause a second revoke,
* which hits an assertion error.
*/
JBUFFER_TRACE(jh, "cancelling revoke");
jbd2_journal_cancel_revoke(handle, jh);
out:
jbd2_journal_put_journal_head(jh);
return err;
}

/**
- * int jbd2_journal_get_undo_access() - Notify intent to modify metadata with
+ * jbd2_journal_get_undo_access() - Notify intent to modify metadata with
* non-rewindable consequences
* @handle: transaction
* @bh: buffer to undo
*
* Sometimes there is a need to distinguish between metadata which has
* been committed to disk and that which has not. The ext3fs code uses
* this for freeing and allocating space, we have to make sure that we
* do not reuse freed space until the deallocation has been committed,
* since if we overwrote that space we would make the delete
* un-rewindable in case of a crash.
*
* To deal with that, jbd2_journal_get_undo_access requests write access to a
* buffer for parts of non-rewindable operations such as delete
* operations on the bitmaps. The journaling code must keep a copy of
* the buffer's contents prior to the undo_access call until such time
* as we know that the buffer has definitely been committed to disk.
*
* We never need to know which transaction the committed data is part
* of, buffers touched here are guaranteed to be dirtied later and so
* will be committed to a new transaction in due course, at which point
@@ -1366,41 +1367,41 @@ int jbd2_journal_get_undo_access(handle_t *handle, struct buffer_head *bh)
* preserved, committed copy. */
JBUFFER_TRACE(jh, "generate b_committed data");
if (!committed_data) {
spin_unlock(&jh->b_state_lock);
goto repeat;
}

jh->b_committed_data = committed_data;
committed_data = NULL;
memcpy(jh->b_committed_data, bh->b_data, bh->b_size);
}
spin_unlock(&jh->b_state_lock);
out:
jbd2_journal_put_journal_head(jh);
if (unlikely(committed_data))
jbd2_free(committed_data, bh->b_size);
return err;
}

/**
- * void jbd2_journal_set_triggers() - Add triggers for commit writeout
+ * jbd2_journal_set_triggers() - Add triggers for commit writeout
* @bh: buffer to trigger on
* @type: struct jbd2_buffer_trigger_type containing the trigger(s).
*
* Set any triggers on this journal_head. This is always safe, because
* triggers for a committing buffer will be saved off, and triggers for
* a running transaction will match the buffer in that transaction.
*
* Call with NULL to clear the triggers.
*/
void jbd2_journal_set_triggers(struct buffer_head *bh,
struct jbd2_buffer_trigger_type *type)
{
struct journal_head *jh = jbd2_journal_grab_journal_head(bh);

if (WARN_ON(!jh))
return;
jh->b_triggers = type;
jbd2_journal_put_journal_head(jh);
}

@@ -1408,41 +1409,41 @@ void jbd2_buffer_frozen_trigger(struct journal_head *jh, void *mapped_data,
struct jbd2_buffer_trigger_type *triggers)
{
struct buffer_head *bh = jh2bh(jh);

if (!triggers || !triggers->t_frozen)
return;

triggers->t_frozen(triggers, bh, mapped_data, bh->b_size);
}

void jbd2_buffer_abort_trigger(struct journal_head *jh,
struct jbd2_buffer_trigger_type *triggers)
{
if (!triggers || !triggers->t_abort)
return;

triggers->t_abort(triggers, jh2bh(jh));
}

/**
- * int jbd2_journal_dirty_metadata() - mark a buffer as containing dirty metadata
+ * jbd2_journal_dirty_metadata() - mark a buffer as containing dirty metadata
* @handle: transaction to add buffer to.
* @bh: buffer to mark
*
* mark dirty metadata which needs to be journaled as part of the current
* transaction.
*
* The buffer must have previously had jbd2_journal_get_write_access()
* called so that it has a valid journal_head attached to the buffer
* head.
*
* The buffer is placed on the transaction's metadata list and is marked
* as belonging to the transaction.
*
* Returns error number or 0 on success.
*
* Special care needs to be taken if the buffer already belongs to the
* current committing transaction (in which case we should have frozen
* data present for that commit). In that case, we don't relink the
* buffer: that only gets done when the old transaction finally
* completes its commit.
@@ -1576,41 +1577,41 @@ int jbd2_journal_dirty_metadata(handle_t *handle, struct buffer_head *bh)
/* And this case is illegal: we can't reuse another
* transaction's data buffer, ever. */
goto out_unlock_bh;
}

/* That test should have eliminated the following case: */
J_ASSERT_JH(jh, jh->b_frozen_data == NULL);

JBUFFER_TRACE(jh, "file as BJ_Metadata");
spin_lock(&journal->j_list_lock);
__jbd2_journal_file_buffer(jh, transaction, BJ_Metadata);
spin_unlock(&journal->j_list_lock);
out_unlock_bh:
spin_unlock(&jh->b_state_lock);
out:
JBUFFER_TRACE(jh, "exit");
return ret;
}

/**
- * void jbd2_journal_forget() - bforget() for potentially-journaled buffers.
+ * jbd2_journal_forget() - bforget() for potentially-journaled buffers.
* @handle: transaction handle
* @bh: bh to 'forget'
*
* We can only do the bforget if there are no commits pending against the
* buffer. If the buffer is dirty in the current running transaction we
* can safely unlink it.
*
* bh may not be a journalled buffer at all - it may be a non-JBD
* buffer which came off the hashtable. Check for this.
*
* Decrements bh->b_count by one.
*
* Allow this call even if the handle has aborted --- it may be part of
* the caller's cleanup after an abort.
*/
int jbd2_journal_forget(handle_t *handle, struct buffer_head *bh)
{
transaction_t *transaction = handle->h_transaction;
journal_t *journal;
struct journal_head *jh;
@@ -1745,41 +1746,41 @@ int jbd2_journal_forget(handle_t *handle, struct buffer_head *bh)
* attach this buffer to current transaction so that the
* buffer can be checkpointed only after the current
* transaction commits.
*/
clear_buffer_dirty(bh);
__jbd2_journal_file_buffer(jh, transaction, BJ_Forget);
spin_unlock(&journal->j_list_lock);
}
drop:
__brelse(bh);
spin_unlock(&jh->b_state_lock);
jbd2_journal_put_journal_head(jh);
if (drop_reserve) {
/* no need to reserve log space for this block -bzzz */
handle->h_total_credits++;
}
return err;
}

/**
- * int jbd2_journal_stop() - complete a transaction
+ * jbd2_journal_stop() - complete a transaction
* @handle: transaction to complete.
*
* All done for a particular handle.
*
* There is not much action needed here. We just return any remaining
* buffer credits to the transaction and remove the handle. The only
* complication is that we need to start a commit operation if the
* filesystem is marked for synchronous update.
*
* jbd2_journal_stop itself will not usually return an error, but it may
* do so in unusual circumstances. In particular, expect it to
* return -EIO if a jbd2_journal_abort has been executed since the
* transaction began.
*/
int jbd2_journal_stop(handle_t *handle)
{
transaction_t *transaction = handle->h_transaction;
journal_t *journal;
int err = 0, wait_for_commit = 0;
tid_t tid;
@@ -2063,41 +2064,41 @@ __journal_try_to_free_buffer(journal_t *journal, struct buffer_head *bh)
jh = bh2jh(bh);

if (buffer_locked(bh) || buffer_dirty(bh))
goto out;

if (jh->b_next_transaction != NULL || jh->b_transaction != NULL)
goto out;

spin_lock(&journal->j_list_lock);
if (jh->b_cp_transaction != NULL) {
/* written-back checkpointed metadata buffer */
JBUFFER_TRACE(jh, "remove from checkpoint list");
__jbd2_journal_remove_checkpoint(jh);
}
spin_unlock(&journal->j_list_lock);
out:
return;
}

/**
- * int jbd2_journal_try_to_free_buffers() - try to free page buffers.
+ * jbd2_journal_try_to_free_buffers() - try to free page buffers.
* @journal: journal for operation
* @page: to try and free
*
* For all the buffers on this page,
* if they are fully written out ordered data, move them onto BUF_CLEAN
* so try_to_free_buffers() can reap them.
*
* This function returns non-zero if we wish try_to_free_buffers()
* to be called. We do this if the page is releasable by try_to_free_buffers().
* We also do it if the page has locked or dirty buffers and the caller wants
* us to perform sync or async writeout.
*
* This complicates JBD locking somewhat. We aren't protected by the
* BKL here. We wish to remove the buffer from its committing or
* running transaction's ->t_datalist via __jbd2_journal_unfile_buffer.
*
* This may *change* the value of transaction_t->t_datalist, so anyone
* who looks at t_datalist needs to lock against this function.
*
* Even worse, someone may be doing a jbd2_journal_dirty_data on this
@@ -2394,41 +2395,41 @@ static int journal_unmap_buffer(journal_t *journal, struct buffer_head *bh,
* here.
*/
jh->b_modified = 0;
spin_unlock(&journal->j_list_lock);
spin_unlock(&jh->b_state_lock);
write_unlock(&journal->j_state_lock);
jbd2_journal_put_journal_head(jh);
zap_buffer_unlocked:
clear_buffer_dirty(bh);
J_ASSERT_BH(bh, !buffer_jbddirty(bh));
clear_buffer_mapped(bh);
clear_buffer_req(bh);
clear_buffer_new(bh);
clear_buffer_delay(bh);
clear_buffer_unwritten(bh);
bh->b_bdev = NULL;
return may_free;
}

/**
- * void jbd2_journal_invalidatepage()
+ * jbd2_journal_invalidatepage()
* @journal: journal to use for flush...
* @page: page to flush
* @offset: start of the range to invalidate
* @length: length of the range to invalidate
*
* Reap page buffers containing data after in the specified range in page.
* Can return -EBUSY if buffers are part of the committing transaction and
* the page is straddling i_size. Caller then has to wait for current commit
* and try again.
*/
int jbd2_journal_invalidatepage(journal_t *journal,
struct page *page,
unsigned int offset,
unsigned int length)
{
struct buffer_head *head, *bh, *next;
unsigned int stop = offset + length;
unsigned int curr_off = 0;
int partial_page = (offset || length < PAGE_SIZE);
int may_free = 1;
diff --git a/include/linux/jbd2.h b/include/linux/jbd2.h
index 1c49fd62ff2e..578ff196b3ce 100644
--- a/include/linux/jbd2.h
+++ b/include/linux/jbd2.h
@@ -384,41 +384,41 @@ static inline void jbd_unlock_bh_journal_head(struct buffer_head *bh)
#define J_EXPECT_JH(jh, expr, why...) __journal_expect(expr, ## why)
#endif

/* Flags in jbd_inode->i_flags */
#define __JI_COMMIT_RUNNING 0
#define __JI_WRITE_DATA 1
#define __JI_WAIT_DATA 2

/*
* Commit of the inode data in progress. We use this flag to protect us from
* concurrent deletion of inode. We cannot use reference to inode for this
* since we cannot afford doing last iput() on behalf of kjournald
*/
#define JI_COMMIT_RUNNING (1 << __JI_COMMIT_RUNNING)
/* Write allocated dirty buffers in this inode before commit */
#define JI_WRITE_DATA (1 << __JI_WRITE_DATA)
/* Wait for outstanding data writes for this inode before commit */
#define JI_WAIT_DATA (1 << __JI_WAIT_DATA)

/**
- * struct jbd_inode - The jbd_inode type is the structure linking inodes in
+ * struct jbd2_inode - The jbd_inode type is the structure linking inodes in
* ordered mode present in a transaction so that we can sync them during commit.
*/
struct jbd2_inode {
/**
* @i_transaction:
*
* Which transaction does this inode belong to? Either the running
* transaction or the committing one. [j_list_lock]
*/
transaction_t *i_transaction;

/**
* @i_next_transaction:
*
* Pointer to the running transaction modifying inode's data in case
* there is already a committing transaction touching it. [j_list_lock]
*/
transaction_t *i_next_transaction;

/**
--
2.28.0