Commit 55b66332 authored by Dave Chinner's avatar Dave Chinner Committed by Alex Elder
Browse files

xfs: introduce new internal log vector structure 



The current log IO vector structure is a flat array and not
extensible. To make it possible to keep separate log IO vectors for
individual log items, we need a method of chaining log IO vectors
together.

Introduce a new log vector type that can be used to wrap the
existing log IO vectors on use that internally to the log. This
means that the existing external interface (xfs_log_write) does not
change and hence no changes to the transaction commit code are
required.

Signed-off-by: default avatarChristoph Hellwig <hch@lst.de>
Signed-off-by: default avatarDave Chinner <dchinner@redhat.com>
Reviewed-by: default avatarDave Chinner <dchinner@redhat.com>
parent 99428ad0

fs/xfs/xfs_log.c

+84 −59
Original line number Diff line number Diff line
@@ -50,7 +50,7 @@ kmem_zone_t *xfs_log_ticket_zone; 
	  (off) += (bytes);}



/* Local miscellaneous function prototypes */

STATIC int	 xlog_commit_record(xfs_mount_t *mp, xlog_ticket_t *ticket,

STATIC int	 xlog_commit_record(struct log *log, struct xlog_ticket *ticket,

				    xlog_in_core_t **, xfs_lsn_t *);

STATIC xlog_t *  xlog_alloc_log(xfs_mount_t	*mp,

				xfs_buftarg_t	*log_target,
@@ -59,11 +59,9 @@ STATIC xlog_t * xlog_alloc_log(xfs_mount_t *mp, 
STATIC int	 xlog_space_left(xlog_t *log, int cycle, int bytes);

STATIC int	 xlog_sync(xlog_t *log, xlog_in_core_t *iclog);

STATIC void	 xlog_dealloc_log(xlog_t *log);

STATIC int	 xlog_write(xfs_mount_t *mp, xfs_log_iovec_t region[],

			    int nentries, struct xlog_ticket *tic,

			    xfs_lsn_t *start_lsn,

			    xlog_in_core_t **commit_iclog,

			    uint flags);

STATIC int	 xlog_write(struct log *log, struct xfs_log_vec *log_vector,

			    struct xlog_ticket *tic, xfs_lsn_t *start_lsn,

			    xlog_in_core_t **commit_iclog, uint flags);



/* local state machine functions */

STATIC void xlog_state_done_syncing(xlog_in_core_t *iclog, int);
@@ -258,7 +256,7 @@ xfs_log_done( 
	     * If we get an error, just continue and give back the log ticket.

	     */

	    (((ticket->t_flags & XLOG_TIC_INITED) == 0) &&

	     (xlog_commit_record(mp, ticket, iclog, &lsn)))) {

	     (xlog_commit_record(log, ticket, iclog, &lsn)))) {

		lsn = (xfs_lsn_t) -1;

		if (ticket->t_flags & XLOG_TIC_PERM_RESERV) {

			flags |= XFS_LOG_REL_PERM_RESERV;
@@ -516,18 +514,10 @@ xfs_log_unmount_write(xfs_mount_t *mp) 
#ifdef DEBUG

	xlog_in_core_t	 *first_iclog;

#endif

	xfs_log_iovec_t  reg[1];

	xlog_ticket_t	*tic = NULL;

	xfs_lsn_t	 lsn;

	int		 error;



	/* the data section must be 32 bit size aligned */

	struct {

	    __uint16_t magic;

	    __uint16_t pad1;

	    __uint32_t pad2; /* may as well make it 64 bits */

	} magic = { XLOG_UNMOUNT_TYPE, 0, 0 };



	/*

	 * Don't write out unmount record on read-only mounts.

	 * Or, if we are doing a forced umount (typically because of IO errors).
@@ -549,16 +539,30 @@ xfs_log_unmount_write(xfs_mount_t *mp) 
	} while (iclog != first_iclog);

#endif

	if (! (XLOG_FORCED_SHUTDOWN(log))) {

		reg[0].i_addr = (void*)&magic;

		reg[0].i_len  = sizeof(magic);

		reg[0].i_type = XLOG_REG_TYPE_UNMOUNT;



		error = xfs_log_reserve(mp, 600, 1, &tic,

					XFS_LOG, 0, XLOG_UNMOUNT_REC_TYPE);

		if (!error) {

			/* the data section must be 32 bit size aligned */

			struct {

			    __uint16_t magic;

			    __uint16_t pad1;

			    __uint32_t pad2; /* may as well make it 64 bits */

			} magic = {

				.magic = XLOG_UNMOUNT_TYPE,

			};

			struct xfs_log_iovec reg = {

				.i_addr = (void *)&magic,

				.i_len = sizeof(magic),

				.i_type = XLOG_REG_TYPE_UNMOUNT,

			};

			struct xfs_log_vec vec = {

				.lv_niovecs = 1,

				.lv_iovecp = &reg,

			};



			/* remove inited flag */

			((xlog_ticket_t *)tic)->t_flags = 0;

			error = xlog_write(mp, reg, 1, tic, &lsn,

			tic->t_flags = 0;

			error = xlog_write(log, &vec, tic, &lsn,

					   NULL, XLOG_UNMOUNT_TRANS);

			/*

			 * At this point, we're umounting anyway,
@@ -679,11 +683,15 @@ xfs_log_write( 
{

	struct log		*log = mp->m_log;

	int			error;

	struct xfs_log_vec	vec = {

		.lv_niovecs = nentries,

		.lv_iovecp = reg,

	};



	if (XLOG_FORCED_SHUTDOWN(log))

		return XFS_ERROR(EIO);



	error = xlog_write(mp, reg, nentries, tic, start_lsn, NULL, 0);

	error = xlog_write(log, &vec, tic, start_lsn, NULL, 0);

	if (error)

		xfs_force_shutdown(mp, SHUTDOWN_LOG_IO_ERROR);

	return error;
@@ -1190,26 +1198,31 @@ out: 
 * ticket.  Return the lsn of the commit record.

 */

STATIC int

xlog_commit_record(xfs_mount_t  *mp,

		   xlog_ticket_t *ticket,

		   xlog_in_core_t **iclog,

xlog_commit_record(

	struct log		*log,

	struct xlog_ticket	*ticket,

	struct xlog_in_core	**iclog,

	xfs_lsn_t		*commitlsnp)

{

	struct xfs_mount *mp = log->l_mp;

	int	error;

	xfs_log_iovec_t	reg[1];



	reg[0].i_addr = NULL;

	reg[0].i_len = 0;

	reg[0].i_type = XLOG_REG_TYPE_COMMIT;

	struct xfs_log_iovec reg = {

		.i_addr = NULL,

		.i_len = 0,

		.i_type = XLOG_REG_TYPE_COMMIT,

	};

	struct xfs_log_vec vec = {

		.lv_niovecs = 1,

		.lv_iovecp = &reg,

	};



	ASSERT_ALWAYS(iclog);

	if ((error = xlog_write(mp, reg, 1, ticket, commitlsnp,

			       iclog, XLOG_COMMIT_TRANS))) {

	error = xlog_write(log, &vec, ticket, commitlsnp, iclog,

					XLOG_COMMIT_TRANS);

	if (error)

		xfs_force_shutdown(mp, SHUTDOWN_LOG_IO_ERROR);

	}

	return error;

}	/* xlog_commit_record */



}



/*

 * Push on the buffer cache code if we ever use more than 75% of the on-disk
@@ -1636,9 +1649,9 @@ xlog_print_tic_res(xfs_mount_t *mp, xlog_ticket_t *ticket) 
static int

xlog_write_calc_vec_length(

	struct xlog_ticket	*ticket,

	struct xfs_log_iovec	reg[],

	int			nentries)

	struct xfs_log_vec	*log_vector)

{

	struct xfs_log_vec	*lv;

	int			headers = 0;

	int			len = 0;

	int			i;
@@ -1647,12 +1660,15 @@ xlog_write_calc_vec_length( 
	if (ticket->t_flags & XLOG_TIC_INITED)

		headers++;



	for (i = 0; i < nentries; i++) {

		/* each region gets >= 1 */

		headers++;

	for (lv = log_vector; lv; lv = lv->lv_next) {

		headers += lv->lv_niovecs;



		for (i = 0; i < lv->lv_niovecs; i++) {

			struct xfs_log_iovec	*vecp = &lv->lv_iovecp[i];



		len += reg[i].i_len;

		xlog_tic_add_region(ticket, reg[i].i_len, reg[i].i_type);

			len += vecp->i_len;

			xlog_tic_add_region(ticket, vecp->i_len, vecp->i_type);

		}

	}



	ticket->t_res_num_ophdrs += headers;
@@ -1858,16 +1874,16 @@ xlog_write_copy_finish( 
 */

STATIC int

xlog_write(

	struct xfs_mount	*mp,

	struct xfs_log_iovec	reg[],

	int			nentries,

	struct log		*log,

	struct xfs_log_vec	*log_vector,

	struct xlog_ticket	*ticket,

	xfs_lsn_t		*start_lsn,

	struct xlog_in_core	**commit_iclog,

	uint			flags)

{

	struct log		*log = mp->m_log;

	struct xlog_in_core	*iclog = NULL;

	struct xfs_log_iovec	*vecp;

	struct xfs_log_vec	*lv;

	int			len;

	int			index;

	int			partial_copy = 0;
@@ -1879,25 +1895,28 @@ xlog_write( 


	*start_lsn = 0;



	len = xlog_write_calc_vec_length(ticket, reg, nentries);

	len = xlog_write_calc_vec_length(ticket, log_vector);

	if (ticket->t_curr_res < len) {

		xlog_print_tic_res(mp, ticket);

		xlog_print_tic_res(log->l_mp, ticket);

#ifdef DEBUG

		xlog_panic(

	"xfs_log_write: reservation ran out. Need to up reservation");

#else

		/* Customer configurable panic */

		xfs_cmn_err(XFS_PTAG_LOGRES, CE_ALERT, mp,

		xfs_cmn_err(XFS_PTAG_LOGRES, CE_ALERT, log->l_mp,

	"xfs_log_write: reservation ran out. Need to up reservation");



		/* If we did not panic, shutdown the filesystem */

		xfs_force_shutdown(mp, SHUTDOWN_CORRUPT_INCORE);

		xfs_force_shutdown(log->l_mp, SHUTDOWN_CORRUPT_INCORE);

#endif

	}



	ticket->t_curr_res -= len;



	for (index = 0; index < nentries; ) {

	index = 0;

	lv = log_vector;

	vecp = lv->lv_iovecp;

	while (lv && index < lv->lv_niovecs) {

		__psint_t	ptr;

		int		log_offset;
@@ -1917,13 +1936,14 @@ xlog_write( 
		 * This loop writes out as many regions as can fit in the amount

		 * of space which was allocated by xlog_state_get_iclog_space().

		 */

		while (index < nentries) {

		while (lv && index < lv->lv_niovecs) {

			struct xfs_log_iovec	*reg = &vecp[index];

			struct xlog_op_header	*ophdr;

			int			start_rec_copy;

			int			copy_len;

			int			copy_off;



			ASSERT(reg[index].i_len % sizeof(__int32_t) == 0);

			ASSERT(reg->i_len % sizeof(__int32_t) == 0);

			ASSERT((__psint_t)ptr % sizeof(__int32_t) == 0);



			start_rec_copy = xlog_write_start_rec(ptr, ticket);
@@ -1942,7 +1962,7 @@ xlog_write( 


			len += xlog_write_setup_copy(ticket, ophdr,

						     iclog->ic_size-log_offset,

						     reg[index].i_len,

						     reg->i_len,

						     &copy_off, &copy_len,

						     &partial_copy,

						     &partial_copy_len);
@@ -1950,7 +1970,7 @@ xlog_write( 


			/* copy region */

			ASSERT(copy_len >= 0);

			memcpy((xfs_caddr_t)ptr, reg[index].i_addr + copy_off,

			memcpy((xfs_caddr_t)ptr, reg->i_addr + copy_off,

			       copy_len);

			xlog_write_adv_cnt(ptr, len, log_offset, copy_len);
@@ -1982,9 +2002,14 @@ xlog_write( 
			if (partial_copy)

				break;



			index++;

			if (++index == lv->lv_niovecs) {

				lv = lv->lv_next;

				index = 0;

				if (lv)

					vecp = lv->lv_iovecp;

			}

			if (record_cnt == 0) {

				if (index == nentries)

				if (!lv)

					return 0;

				break;

			}

fs/xfs/xfs_log.h

+6 −0
Original line number Diff line number Diff line
@@ -110,6 +110,12 @@ typedef struct xfs_log_iovec { 
	uint		i_type;		/* type of region */

} xfs_log_iovec_t;



struct xfs_log_vec {

	struct xfs_log_vec	*lv_next;	/* next lv in build list */

	int			lv_niovecs;	/* number of iovecs in lv */

	struct xfs_log_iovec	*lv_iovecp;	/* iovec array */

};



/*

 * Structure used to pass callback function and the function's argument

 * to the log manager.

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