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: Christoph Hellwig <hch@lst.de>
Signed-off-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Dave Chinner <dchinner@redhat.com>
diff --git a/fs/xfs/xfs_log.c b/fs/xfs/xfs_log.c
index 8c856d2..2e6f3b8 100644
--- a/fs/xfs/xfs_log.c
+++ b/fs/xfs/xfs_log.c
@@ -50,7 +50,7 @@
(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 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 @@
* 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 @@
#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 @@
} 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 = ®,
+ };
+
/* 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 @@
{
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 @@
* 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,
- xfs_lsn_t *commitlsnp)
+xlog_commit_record(
+ struct log *log,
+ struct xlog_ticket *ticket,
+ struct xlog_in_core **iclog,
+ xfs_lsn_t *commitlsnp)
{
- 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_mount *mp = log->l_mp;
+ int error;
+ 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 = ®,
+ };
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 @@
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 @@
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;
- len += reg[i].i_len;
- xlog_tic_add_region(ticket, reg[i].i_len, reg[i].i_type);
+ for (i = 0; i < lv->lv_niovecs; i++) {
+ struct xfs_log_iovec *vecp = &lv->lv_iovecp[i];
+
+ 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 @@
*/
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 @@
*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 @@
* 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 @@
len += xlog_write_setup_copy(ticket, ophdr,
iclog->ic_size-log_offset,
- reg[index].i_len,
+ reg->i_len,
©_off, ©_len,
&partial_copy,
&partial_copy_len);
@@ -1950,7 +1970,7 @@
/* 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 @@
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;
}