[PATCH 4.9 06/77] jbd2: fix sphinx kernel-doc build warnings

4.9-stable review patch. If anyone has any objections, please let me know.

------------------

From: Tobin C. Harding me@tobin.cc

commit f69120ce6c024aa634a8fc25787205e42f0ccbe6 upstream.

Sphinx emits various (26) warnings when building make target 'htmldocs'. Currently struct definitions contain duplicate documentation, some as kernel-docs and some as standard c89 comments. We can reduce duplication while cleaning up the kernel docs.

Move all kernel-docs to right above each struct member. Use the set of all existing comments (kernel-doc and c89). Add documentation for missing struct members and function arguments.

Signed-off-by: Tobin C. Harding me@tobin.cc Signed-off-by: Theodore Ts'o tytso@mit.edu Cc: stable@vger.kernel.org Signed-off-by: Greg Kroah-Hartman gregkh@linuxfoundation.org

--- fs/jbd2/transaction.c | 5 include/linux/jbd2.h | 431 +++++++++++++++++++++++++++++++------------------- 2 files changed, 272 insertions(+), 164 deletions(-)

--- a/fs/jbd2/transaction.c +++ b/fs/jbd2/transaction.c @@ -488,8 +488,10 @@ void jbd2_journal_free_reserved(handle_t EXPORT_SYMBOL(jbd2_journal_free_reserved);

/** - * int jbd2_journal_start_reserved(handle_t *handle) - start reserved handle + * int 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 @@ -619,6 +621,7 @@ error_out: * int jbd2_journal_restart() - restart a handle . * @handle: handle to restart * @nblocks: nr credits requested + * @gfp_mask: memory allocation flags (for start_this_handle) * * Restart a handle for a multi-transaction filesystem * operation. --- a/include/linux/jbd2.h +++ b/include/linux/jbd2.h @@ -418,26 +418,41 @@ static inline void jbd_unlock_bh_journal #define JI_WAIT_DATA (1 << __JI_WAIT_DATA)

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

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

- /* List of inodes in the i_transaction [j_list_lock] */ + /** + * @i_list: List of inodes in the i_transaction [j_list_lock] + */ struct list_head i_list;

- /* VFS inode this inode belongs to [constant during the lifetime - * of the structure] */ + /** + * @i_vfs_inode: + * + * VFS inode this inode belongs to [constant for lifetime of structure] + */ struct inode *i_vfs_inode;

- /* Flags of inode [j_list_lock] */ + /** + * @i_flags: Flags of inode [j_list_lock] + */ unsigned long i_flags; };

@@ -447,12 +462,20 @@ struct jbd2_revoke_table_s; * struct handle_s - The handle_s type is the concrete type associated with * handle_t. * @h_transaction: Which compound transaction is this update a part of? + * @h_journal: Which journal handle belongs to - used iff h_reserved set. + * @h_rsv_handle: Handle reserved for finishing the logical operation. * @h_buffer_credits: Number of remaining buffers we are allowed to dirty. - * @h_ref: Reference count on this handle - * @h_err: Field for caller's use to track errors through large fs operations - * @h_sync: flag for sync-on-close - * @h_jdata: flag to force data journaling - * @h_aborted: flag indicating fatal error on handle + * @h_ref: Reference count on this handle. + * @h_err: Field for caller's use to track errors through large fs operations. + * @h_sync: Flag for sync-on-close. + * @h_jdata: Flag to force data journaling. + * @h_reserved: Flag for handle for reserved credits. + * @h_aborted: Flag indicating fatal error on handle. + * @h_type: For handle statistics. + * @h_line_no: For handle statistics. + * @h_start_jiffies: Handle Start time. + * @h_requested_credits: Holds @h_buffer_credits after handle is started. + * @saved_alloc_context: Saved context while transaction is open. **/

/* Docbook can't yet cope with the bit fields, but will leave the documentation @@ -462,32 +485,23 @@ struct jbd2_revoke_table_s; struct jbd2_journal_handle { union { - /* Which compound transaction is this update a part of? */ transaction_t *h_transaction; /* Which journal handle belongs to - used iff h_reserved set */ journal_t *h_journal; };

- /* Handle reserved for finishing the logical operation */ handle_t *h_rsv_handle; - - /* Number of remaining buffers we are allowed to dirty: */ int h_buffer_credits; - - /* Reference count on this handle */ int h_ref; - - /* Field for caller's use to track errors through large fs */ - /* operations */ int h_err;

/* Flags [no locking] */ - unsigned int h_sync: 1; /* sync-on-close */ - unsigned int h_jdata: 1; /* force data journaling */ - unsigned int h_reserved: 1; /* handle with reserved credits */ - unsigned int h_aborted: 1; /* fatal error on handle */ - unsigned int h_type: 8; /* for handle statistics */ - unsigned int h_line_no: 16; /* for handle statistics */ + unsigned int h_sync: 1; + unsigned int h_jdata: 1; + unsigned int h_reserved: 1; + unsigned int h_aborted: 1; + unsigned int h_type: 8; + unsigned int h_line_no: 16;

unsigned long h_start_jiffies; unsigned int h_requested_credits; @@ -727,228 +741,253 @@ jbd2_time_diff(unsigned long start, unsi /** * struct journal_s - The journal_s type is the concrete type associated with * journal_t. - * @j_flags: General journaling state flags - * @j_errno: Is there an outstanding uncleared error on the journal (from a - * prior abort)? - * @j_sb_buffer: First part of superblock buffer - * @j_superblock: Second part of superblock buffer - * @j_format_version: Version of the superblock format - * @j_state_lock: Protect the various scalars in the journal - * @j_barrier_count: Number of processes waiting to create a barrier lock - * @j_barrier: The barrier lock itself - * @j_running_transaction: The current running transaction.. - * @j_committing_transaction: the transaction we are pushing to disk - * @j_checkpoint_transactions: a linked circular list of all transactions - * waiting for checkpointing - * @j_wait_transaction_locked: Wait queue for waiting for a locked transaction - * to start committing, or for a barrier lock to be released - * @j_wait_done_commit: Wait queue for waiting for commit to complete - * @j_wait_commit: Wait queue to trigger commit - * @j_wait_updates: Wait queue to wait for updates to complete - * @j_wait_reserved: Wait queue to wait for reserved buffer credits to drop - * @j_checkpoint_mutex: Mutex for locking against concurrent checkpoints - * @j_head: Journal head - identifies the first unused block in the journal - * @j_tail: Journal tail - identifies the oldest still-used block in the - * journal. - * @j_free: Journal free - how many free blocks are there in the journal? - * @j_first: The block number of the first usable block - * @j_last: The block number one beyond the last usable block - * @j_dev: Device where we store the journal - * @j_blocksize: blocksize for the location where we store the journal. - * @j_blk_offset: starting block offset for into the device where we store the - * journal - * @j_fs_dev: Device which holds the client fs. For internal journal this will - * be equal to j_dev - * @j_reserved_credits: Number of buffers reserved from the running transaction - * @j_maxlen: Total maximum capacity of the journal region on disk. - * @j_list_lock: Protects the buffer lists and internal buffer state. - * @j_inode: Optional inode where we store the journal. If present, all journal - * block numbers are mapped into this inode via bmap(). - * @j_tail_sequence: Sequence number of the oldest transaction in the log - * @j_transaction_sequence: Sequence number of the next transaction to grant - * @j_commit_sequence: Sequence number of the most recently committed - * transaction - * @j_commit_request: Sequence number of the most recent transaction wanting - * commit - * @j_uuid: Uuid of client object. - * @j_task: Pointer to the current commit thread for this journal - * @j_max_transaction_buffers: Maximum number of metadata buffers to allow in a - * single compound commit transaction - * @j_commit_interval: What is the maximum transaction lifetime before we begin - * a commit? - * @j_commit_timer: The timer used to wakeup the commit thread - * @j_revoke_lock: Protect the revoke table - * @j_revoke: The revoke table - maintains the list of revoked blocks in the - * current transaction. - * @j_revoke_table: alternate revoke tables for j_revoke - * @j_wbuf: array of buffer_heads for jbd2_journal_commit_transaction - * @j_wbufsize: maximum number of buffer_heads allowed in j_wbuf, the - * number that will fit in j_blocksize - * @j_last_sync_writer: most recent pid which did a synchronous write - * @j_history_lock: Protect the transactions statistics history - * @j_proc_entry: procfs entry for the jbd statistics directory - * @j_stats: Overall statistics - * @j_private: An opaque pointer to fs-private information. - * @j_trans_commit_map: Lockdep entity to track transaction commit dependencies */ - struct journal_s { - /* General journaling state flags [j_state_lock] */ + /** + * @j_flags: General journaling state flags [j_state_lock] + */ unsigned long j_flags;

- /* + /** + * @j_errno: + * * Is there an outstanding uncleared error on the journal (from a prior * abort)? [j_state_lock] */ int j_errno;

- /* The superblock buffer */ + /** + * @j_sb_buffer: The first part of the superblock buffer. + */ struct buffer_head *j_sb_buffer; + + /** + * @j_superblock: The second part of the superblock buffer. + */ journal_superblock_t *j_superblock;

- /* Version of the superblock format */ + /** + * @j_format_version: Version of the superblock format. + */ int j_format_version;

- /* - * Protect the various scalars in the journal + /** + * @j_state_lock: Protect the various scalars in the journal. */ rwlock_t j_state_lock;

- /* + /** + * @j_barrier_count: + * * Number of processes waiting to create a barrier lock [j_state_lock] */ int j_barrier_count;

- /* The barrier lock itself */ + /** + * @j_barrier: The barrier lock itself. + */ struct mutex j_barrier;

- /* + /** + * @j_running_transaction: + * * Transactions: The current running transaction... * [j_state_lock] [caller holding open handle] */ transaction_t *j_running_transaction;

- /* + /** + * @j_committing_transaction: + * * the transaction we are pushing to disk * [j_state_lock] [caller holding open handle] */ transaction_t *j_committing_transaction;

- /* + /** + * @j_checkpoint_transactions: + * * ... and a linked circular list of all transactions waiting for * checkpointing. [j_list_lock] */ transaction_t *j_checkpoint_transactions;

- /* + /** + * @j_wait_transaction_locked: + * * Wait queue for waiting for a locked transaction to start committing, - * or for a barrier lock to be released + * or for a barrier lock to be released. */ wait_queue_head_t j_wait_transaction_locked;

- /* Wait queue for waiting for commit to complete */ + /** + * @j_wait_done_commit: Wait queue for waiting for commit to complete. + */ wait_queue_head_t j_wait_done_commit;

- /* Wait queue to trigger commit */ + /** + * @j_wait_commit: Wait queue to trigger commit. + */ wait_queue_head_t j_wait_commit;

- /* Wait queue to wait for updates to complete */ + /** + * @j_wait_updates: Wait queue to wait for updates to complete. + */ wait_queue_head_t j_wait_updates;

- /* Wait queue to wait for reserved buffer credits to drop */ + /** + * @j_wait_reserved: + * + * Wait queue to wait for reserved buffer credits to drop. + */ wait_queue_head_t j_wait_reserved;

- /* Semaphore for locking against concurrent checkpoints */ + /** + * @j_checkpoint_mutex: + * + * Semaphore for locking against concurrent checkpoints. + */ struct mutex j_checkpoint_mutex;

- /* + /** + * @j_chkpt_bhs: + * * List of buffer heads used by the checkpoint routine. This * was moved from jbd2_log_do_checkpoint() to reduce stack * usage. Access to this array is controlled by the - * j_checkpoint_mutex. [j_checkpoint_mutex] + * @j_checkpoint_mutex. [j_checkpoint_mutex] */ struct buffer_head *j_chkpt_bhs[JBD2_NR_BATCH]; - - /* + + /** + * @j_head: + * * Journal head: identifies the first unused block in the journal. * [j_state_lock] */ unsigned long j_head;

- /* + /** + * @j_tail: + * * Journal tail: identifies the oldest still-used block in the journal. * [j_state_lock] */ unsigned long j_tail;

- /* + /** + * @j_free: + * * Journal free: how many free blocks are there in the journal? * [j_state_lock] */ unsigned long j_free;

- /* - * Journal start and end: the block numbers of the first usable block - * and one beyond the last usable block in the journal. [j_state_lock] + /** + * @j_first: + * + * The block number of the first usable block in the journal + * [j_state_lock]. */ unsigned long j_first; + + /** + * @j_last: + * + * The block number one beyond the last usable block in the journal + * [j_state_lock]. + */ unsigned long j_last;

- /* - * Device, blocksize and starting block offset for the location where we - * store the journal. + /** + * @j_dev: Device where we store the journal. */ struct block_device *j_dev; + + /** + * @j_blocksize: Block size for the location where we store the journal. + */ int j_blocksize; + + /** + * @j_blk_offset: + * + * Starting block offset into the device where we store the journal. + */ unsigned long long j_blk_offset; + + /** + * @j_devname: Journal device name. + */ char j_devname[BDEVNAME_SIZE+24];

- /* + /** + * @j_fs_dev: + * * Device which holds the client fs. For internal journal this will be * equal to j_dev. */ struct block_device *j_fs_dev;

- /* Total maximum capacity of the journal region on disk. */ + /** + * @j_maxlen: Total maximum capacity of the journal region on disk. + */ unsigned int j_maxlen;

- /* Number of buffers reserved from the running transaction */ + /** + * @j_reserved_credits: + * + * Number of buffers reserved from the running transaction. + */ atomic_t j_reserved_credits;

- /* - * Protects the buffer lists and internal buffer state. + /** + * @j_list_lock: Protects the buffer lists and internal buffer state. */ spinlock_t j_list_lock;

- /* Optional inode where we store the journal. If present, all */ - /* journal block numbers are mapped into this inode via */ - /* bmap(). */ + /** + * @j_inode: + * + * Optional inode where we store the journal. If present, all + * journal block numbers are mapped into this inode via bmap(). + */ struct inode *j_inode;

- /* + /** + * @j_tail_sequence: + * * Sequence number of the oldest transaction in the log [j_state_lock] */ tid_t j_tail_sequence;

- /* + /** + * @j_transaction_sequence: + * * Sequence number of the next transaction to grant [j_state_lock] */ tid_t j_transaction_sequence;

- /* + /** + * @j_commit_sequence: + * * Sequence number of the most recently committed transaction * [j_state_lock]. */ tid_t j_commit_sequence;

- /* + /** + * @j_commit_request: + * * Sequence number of the most recent transaction wanting commit * [j_state_lock] */ tid_t j_commit_request;

- /* + /** + * @j_uuid: + * * Journal uuid: identifies the object (filesystem, LVM volume etc) * backed by this journal. This will eventually be replaced by an array * of uuids, allowing us to index multiple devices within a single @@ -956,85 +995,151 @@ struct journal_s */ __u8 j_uuid[16];

- /* Pointer to the current commit thread for this journal */ + /** + * @j_task: Pointer to the current commit thread for this journal. + */ struct task_struct *j_task;

- /* + /** + * @j_max_transaction_buffers: + * * Maximum number of metadata buffers to allow in a single compound - * commit transaction + * commit transaction. */ int j_max_transaction_buffers;

- /* + /** + * @j_commit_interval: + * * What is the maximum transaction lifetime before we begin a commit? */ unsigned long j_commit_interval;

- /* The timer used to wakeup the commit thread: */ + /** + * @j_commit_timer: The timer used to wakeup the commit thread. + */ struct timer_list j_commit_timer;

- /* - * The revoke table: maintains the list of revoked blocks in the - * current transaction. [j_revoke_lock] + /** + * @j_revoke_lock: Protect the revoke table. */ spinlock_t j_revoke_lock; + + /** + * @j_revoke: + * + * The revoke table - maintains the list of revoked blocks in the + * current transaction. + */ struct jbd2_revoke_table_s *j_revoke; + + /** + * @j_revoke_table: Alternate revoke tables for j_revoke. + */ struct jbd2_revoke_table_s *j_revoke_table[2];

- /* - * array of bhs for jbd2_journal_commit_transaction + /** + * @j_wbuf: Array of bhs for jbd2_journal_commit_transaction. */ struct buffer_head **j_wbuf; + + /** + * @j_wbufsize: + * + * Size of @j_wbuf array. + */ int j_wbufsize;

- /* - * this is the pid of hte last person to run a synchronous operation - * through the journal + /** + * @j_last_sync_writer: + * + * The pid of the last person to run a synchronous operation + * through the journal. */ pid_t j_last_sync_writer;

- /* - * the average amount of time in nanoseconds it takes to commit a + /** + * @j_average_commit_time: + * + * The average amount of time in nanoseconds it takes to commit a * transaction to disk. [j_state_lock] */ u64 j_average_commit_time;

- /* - * minimum and maximum times that we should wait for - * additional filesystem operations to get batched into a - * synchronous handle in microseconds + /** + * @j_min_batch_time: + * + * Minimum time that we should wait for additional filesystem operations + * to get batched into a synchronous handle in microseconds. */ u32 j_min_batch_time; + + /** + * @j_max_batch_time: + * + * Maximum time that we should wait for additional filesystem operations + * to get batched into a synchronous handle in microseconds. + */ u32 j_max_batch_time;

- /* This function is called when a transaction is closed */ + /** + * @j_commit_callback: + * + * This function is called when a transaction is closed. + */ void (*j_commit_callback)(journal_t *, transaction_t *);

/* * Journal statistics */ + + /** + * @j_history_lock: Protect the transactions statistics history. + */ spinlock_t j_history_lock; + + /** + * @j_proc_entry: procfs entry for the jbd statistics directory. + */ struct proc_dir_entry *j_proc_entry; + + /** + * @j_stats: Overall statistics. + */ struct transaction_stats_s j_stats;

- /* Failed journal commit ID */ + /** + * @j_failed_commit: Failed journal commit ID. + */ unsigned int j_failed_commit;

- /* + /** + * @j_private: + * * An opaque pointer to fs-private information. ext3 puts its - * superblock pointer here + * superblock pointer here. */ void *j_private;

- /* Reference to checksum algorithm driver via cryptoapi */ + /** + * @j_chksum_driver: + * + * Reference to checksum algorithm driver via cryptoapi. + */ struct crypto_shash *j_chksum_driver;

- /* Precomputed journal UUID checksum for seeding other checksums */ + /** + * @j_csum_seed: + * + * Precomputed journal UUID checksum for seeding other checksums. + */ __u32 j_csum_seed;

#ifdef CONFIG_DEBUG_LOCK_ALLOC - /* + /** + * @j_trans_commit_map: + * * Lockdep entity to track transaction commit dependencies. Handles * hold this "lock" for read, when we wait for commit, we acquire the * "lock" for writing. This matches the properties of jbd2 journalling