/**
* Implementation of the llog_operations::lop_prev_block
*
* This function finds the llog block to return which contains
* record with required index but in reverse order - from end of llog
* to the beginning.
* It is main part of reverse llog processing.
*
* \param[in] env execution environment
* \param[in] loghandle llog handle of the current llog
* \param[in] prev_idx target index to find
* \param[in] buf pointer to data buffer to fill
* \param[in] len required len to read, it is LLOG_CHUNK_SIZE usually.
*
* \retval 0 on successful buffer read
* \retval negative value on error
*/
static int llog_osd_prev_block(const struct lu_env *env,
struct llog_handle *loghandle,
int prev_idx, void *buf, int len)
{
struct llog_thread_info *lgi = llog_info(env);
struct dt_object *o;
struct dt_device *dt;
loff_t cur_offset;
int rc;
ENTRY;
if (len == 0 || len & (LLOG_CHUNK_SIZE - 1))
RETURN(-EINVAL);
CDEBUG(D_OTHER, "looking for log index %u\n", prev_idx);
LASSERT(loghandle);
LASSERT(loghandle->lgh_ctxt);
o = loghandle->lgh_obj;
LASSERT(o);
LASSERT(dt_object_exists(o));
dt = lu2dt_dev(o->do_lu.lo_dev);
LASSERT(dt);
cur_offset = LLOG_CHUNK_SIZE;
llog_skip_over(&cur_offset, 0, prev_idx);
rc = dt_attr_get(env, o, &lgi->lgi_attr, BYPASS_CAPA);
if (rc)
GOTO(out, rc);
while (cur_offset < lgi->lgi_attr.la_size) {
struct llog_rec_hdr *rec, *last_rec;
struct llog_rec_tail *tail;
lgi->lgi_buf.lb_len = len;
lgi->lgi_buf.lb_buf = buf;
rc = dt_read(env, o, &lgi->lgi_buf, &cur_offset);
if (rc < 0) {
CERROR("%s: can't read llog block from log "DFID
" offset "LPU64": rc = %d\n",
o->do_lu.lo_dev->ld_obd->obd_name,
PFID(lu_object_fid(&o->do_lu)), cur_offset, rc);
GOTO(out, rc);
}
if (rc == 0) /* end of file, nothing to do */
GOTO(out, rc);
if (rc < sizeof(*tail)) {
CERROR("%s: invalid llog block at log id "DOSTID"/%u "
"offset "LPU64"\n",
o->do_lu.lo_dev->ld_obd->obd_name,
POSTID(&loghandle->lgh_id.lgl_oi),
loghandle->lgh_id.lgl_ogen, cur_offset);
GOTO(out, rc = -EINVAL);
}
rec = buf;
if (LLOG_REC_HDR_NEEDS_SWABBING(rec))
lustre_swab_llog_rec(rec);
tail = (struct llog_rec_tail *)((char *)buf + rc -
sizeof(struct llog_rec_tail));
/* get the last record in block */
last_rec = (struct llog_rec_hdr *)((char *)buf + rc -
le32_to_cpu(tail->lrt_len));
if (LLOG_REC_HDR_NEEDS_SWABBING(last_rec))
lustre_swab_llog_rec(last_rec);
LASSERT(last_rec->lrh_index == tail->lrt_index);
/* this shouldn't happen */
if (tail->lrt_index == 0) {
CERROR("%s: invalid llog tail at log id "DOSTID"/%u "
"offset "LPU64"\n",
o->do_lu.lo_dev->ld_obd->obd_name,
POSTID(&loghandle->lgh_id.lgl_oi),
loghandle->lgh_id.lgl_ogen, cur_offset);
GOTO(out, rc = -EINVAL);
}
if (tail->lrt_index < prev_idx)
continue;
/* sanity check that the start of the new buffer is no farther
* than the record that we wanted. This shouldn't happen. */
if (rec->lrh_index > prev_idx) {
CERROR("%s: missed desired record? %u > %u\n",
o->do_lu.lo_dev->ld_obd->obd_name,
rec->lrh_index, prev_idx);
GOTO(out, rc = -ENOENT);
}
GOTO(out, rc = 0);
}
GOTO(out, rc = -EIO);
out:
return rc;
}
static int out_read(struct tgt_session_info *tsi)
{
const struct lu_env *env = tsi->tsi_env;
struct tgt_thread_info *tti = tgt_th_info(env);
struct object_update *update = tti->tti_u.update.tti_update;
struct dt_object *obj = tti->tti_u.update.tti_dt_object;
struct object_update_reply *reply = tti->tti_u.update.tti_update_reply;
int index = tti->tti_u.update.tti_update_reply_index;
struct lu_rdbuf *rdbuf;
struct object_update_result *update_result;
struct out_read_reply *orr;
void *tmp;
size_t size;
size_t total_size = 0;
__u64 pos;
unsigned int i;
unsigned int nbufs;
int rc = 0;
ENTRY;
update_result = object_update_result_get(reply, index, NULL);
LASSERT(update_result != NULL);
update_result->our_datalen = sizeof(*orr);
if (!lu_object_exists(&obj->do_lu))
GOTO(out, rc = -ENOENT);
tmp = object_update_param_get(update, 0, NULL);
if (IS_ERR(tmp)) {
CERROR("%s: empty size for read: rc = %ld\n",
tgt_name(tsi->tsi_tgt), PTR_ERR(tmp));
GOTO(out, rc = PTR_ERR(tmp));
}
size = le64_to_cpu(*(size_t *)(tmp));
tmp = object_update_param_get(update, 1, NULL);
if (IS_ERR(tmp)) {
CERROR("%s: empty pos for read: rc = %ld\n",
tgt_name(tsi->tsi_tgt), PTR_ERR(tmp));
GOTO(out, rc = PTR_ERR(tmp));
}
pos = le64_to_cpu(*(__u64 *)(tmp));
/* Put the offset into the begining of the buffer in reply */
orr = (struct out_read_reply *)update_result->our_data;
nbufs = (size + OUT_BULK_BUFFER_SIZE - 1) / OUT_BULK_BUFFER_SIZE;
OBD_ALLOC(rdbuf, sizeof(struct lu_rdbuf) +
nbufs * sizeof(rdbuf->rb_bufs[0]));
if (rdbuf == NULL)
GOTO(out, rc = -ENOMEM);
rdbuf->rb_nbufs = 0;
total_size = 0;
for (i = 0; i < nbufs; i++) {
__u32 read_size;
read_size = size > OUT_BULK_BUFFER_SIZE ?
OUT_BULK_BUFFER_SIZE : size;
OBD_ALLOC(rdbuf->rb_bufs[i].lb_buf, read_size);
if (rdbuf->rb_bufs[i].lb_buf == NULL)
GOTO(out_free, rc = -ENOMEM);
rdbuf->rb_bufs[i].lb_len = read_size;
dt_read_lock(env, obj, MOR_TGT_CHILD);
rc = dt_read(env, obj, &rdbuf->rb_bufs[i], &pos);
dt_read_unlock(env, obj);
total_size += rc < 0 ? 0 : rc;
if (rc <= 0)
break;
rdbuf->rb_nbufs++;
size -= read_size;
}
/* send pages to client */
rc = tgt_send_buffer(tsi, rdbuf);
if (rc < 0)
GOTO(out_free, rc);
orr->orr_size = total_size;
orr->orr_offset = pos;
orr_cpu_to_le(orr, orr);
update_result->our_datalen += orr->orr_size;
out_free:
for (i = 0; i < nbufs; i++) {
if (rdbuf->rb_bufs[i].lb_buf != NULL) {
OBD_FREE(rdbuf->rb_bufs[i].lb_buf,
rdbuf->rb_bufs[i].lb_len);
}
}
OBD_FREE(rdbuf, sizeof(struct lu_rdbuf) +
nbufs * sizeof(rdbuf->rb_bufs[0]));
out:
/* Insert read buffer */
update_result->our_rc = ptlrpc_status_hton(rc);
reply->ourp_lens[index] = cfs_size_round(update_result->our_datalen +
sizeof(*update_result));
RETURN(rc);
}
/* sets:
* - cur_offset to the furthest point read in the log file
* - cur_idx to the log index preceeding cur_offset
* returns -EIO/-EINVAL on error
*/
static int llog_osd_next_block(const struct lu_env *env,
struct llog_handle *loghandle, int *cur_idx,
int next_idx, __u64 *cur_offset, void *buf,
int len)
{
struct llog_thread_info *lgi = llog_info(env);
struct dt_object *o;
struct dt_device *dt;
int rc;
ENTRY;
LASSERT(env);
LASSERT(lgi);
if (len == 0 || len & (LLOG_CHUNK_SIZE - 1))
RETURN(-EINVAL);
CDEBUG(D_OTHER, "looking for log index %u (cur idx %u off "LPU64")\n",
next_idx, *cur_idx, *cur_offset);
LASSERT(loghandle);
LASSERT(loghandle->lgh_ctxt);
o = loghandle->lgh_obj;
LASSERT(o);
LASSERT(dt_object_exists(o));
dt = lu2dt_dev(o->do_lu.lo_dev);
LASSERT(dt);
rc = dt_attr_get(env, o, &lgi->lgi_attr, BYPASS_CAPA);
if (rc)
GOTO(out, rc);
while (*cur_offset < lgi->lgi_attr.la_size) {
struct llog_rec_hdr *rec, *last_rec;
struct llog_rec_tail *tail;
llog_skip_over(cur_offset, *cur_idx, next_idx);
/* read up to next LLOG_CHUNK_SIZE block */
lgi->lgi_buf.lb_len = LLOG_CHUNK_SIZE -
(*cur_offset & (LLOG_CHUNK_SIZE - 1));
lgi->lgi_buf.lb_buf = buf;
/* Note: read lock is not needed around la_size get above at
* the time of dt_attr_get(). There are only two cases that
* matter. Either la_size == cur_offset, in which case the
* entire read is skipped, or la_size > cur_offset and the loop
* is entered and this thread is blocked at dt_read_lock()
* until the write is completed. When the write completes, then
* the dt_read() will be done with the full length, and will
* get the full data.
*/
dt_read_lock(env, o, 0);
rc = dt_read(env, o, &lgi->lgi_buf, cur_offset);
dt_read_unlock(env, o);
if (rc < 0) {
CERROR("%s: can't read llog block from log "DFID
" offset "LPU64": rc = %d\n",
o->do_lu.lo_dev->ld_obd->obd_name,
PFID(lu_object_fid(&o->do_lu)), *cur_offset,
rc);
GOTO(out, rc);
}
if (rc < len) {
/* signal the end of the valid buffer to
* llog_process */
memset(buf + rc, 0, len - rc);
}
if (rc == 0) /* end of file, nothing to do */
GOTO(out, rc);
if (rc < sizeof(*tail)) {
CERROR("%s: invalid llog block at log id "LPU64"/%u "
"offset "LPU64"\n",
o->do_lu.lo_dev->ld_obd->obd_name,
loghandle->lgh_id.lgl_oid,
loghandle->lgh_id.lgl_ogen, *cur_offset);
GOTO(out, rc = -EINVAL);
}
rec = buf;
if (LLOG_REC_HDR_NEEDS_SWABBING(rec))
lustre_swab_llog_rec(rec);
tail = (struct llog_rec_tail *)((char *)buf + rc -
sizeof(struct llog_rec_tail));
/* get the last record in block */
last_rec = (struct llog_rec_hdr *)((char *)buf + rc -
le32_to_cpu(tail->lrt_len));
if (LLOG_REC_HDR_NEEDS_SWABBING(last_rec))
lustre_swab_llog_rec(last_rec);
LASSERT(last_rec->lrh_index == tail->lrt_index);
*cur_idx = tail->lrt_index;
/* this shouldn't happen */
if (tail->lrt_index == 0) {
CERROR("%s: invalid llog tail at log id "LPU64"/%u "
"offset "LPU64"\n",
o->do_lu.lo_dev->ld_obd->obd_name,
loghandle->lgh_id.lgl_oid,
loghandle->lgh_id.lgl_ogen, *cur_offset);
GOTO(out, rc = -EINVAL);
}
if (tail->lrt_index < next_idx)
continue;
/* sanity check that the start of the new buffer is no farther
* than the record that we wanted. This shouldn't happen. */
if (rec->lrh_index > next_idx) {
CERROR("%s: missed desired record? %u > %u\n",
o->do_lu.lo_dev->ld_obd->obd_name,
rec->lrh_index, next_idx);
GOTO(out, rc = -ENOENT);
}
GOTO(out, rc = 0);
}
GOTO(out, rc = -EIO);
out:
return rc;
}
/**
* Implementation of the llog_operations::lop_next_block
*
* This function finds the the next llog block to return which contains
* record with required index. It is main part of llog processing.
*
* \param[in] env execution environment
* \param[in] loghandle llog handle of the current llog
* \param[in,out] cur_idx index preceeding cur_offset
* \param[in] next_idx target index to find
* \param[in,out] cur_offset furtherst point read in the file
* \param[in] buf pointer to data buffer to fill
* \param[in] len required len to read, it is
* LLOG_CHUNK_SIZE usually.
*
* \retval 0 on successful buffer read
* \retval negative value on error
*/
static int llog_osd_next_block(const struct lu_env *env,
struct llog_handle *loghandle, int *cur_idx,
int next_idx, __u64 *cur_offset, void *buf,
int len)
{
struct llog_thread_info *lgi = llog_info(env);
struct dt_object *o;
struct dt_device *dt;
int rc;
ENTRY;
LASSERT(env);
LASSERT(lgi);
if (len == 0 || len & (LLOG_CHUNK_SIZE - 1))
RETURN(-EINVAL);
CDEBUG(D_OTHER, "looking for log index %u (cur idx %u off "LPU64")\n",
next_idx, *cur_idx, *cur_offset);
LASSERT(loghandle);
LASSERT(loghandle->lgh_ctxt);
o = loghandle->lgh_obj;
LASSERT(o);
LASSERT(dt_object_exists(o));
dt = lu2dt_dev(o->do_lu.lo_dev);
LASSERT(dt);
rc = dt_attr_get(env, o, &lgi->lgi_attr, BYPASS_CAPA);
if (rc)
GOTO(out, rc);
while (*cur_offset < lgi->lgi_attr.la_size) {
struct llog_rec_hdr *rec, *last_rec;
struct llog_rec_tail *tail;
llog_skip_over(cur_offset, *cur_idx, next_idx);
/* read up to next LLOG_CHUNK_SIZE block */
lgi->lgi_buf.lb_len = LLOG_CHUNK_SIZE -
(*cur_offset & (LLOG_CHUNK_SIZE - 1));
lgi->lgi_buf.lb_buf = buf;
rc = dt_read(env, o, &lgi->lgi_buf, cur_offset);
if (rc < 0) {
CERROR("%s: can't read llog block from log "DFID
" offset "LPU64": rc = %d\n",
o->do_lu.lo_dev->ld_obd->obd_name,
PFID(lu_object_fid(&o->do_lu)), *cur_offset,
rc);
GOTO(out, rc);
}
if (rc < len) {
/* signal the end of the valid buffer to
* llog_process */
memset(buf + rc, 0, len - rc);
}
if (rc == 0) /* end of file, nothing to do */
GOTO(out, rc);
if (rc < sizeof(*tail)) {
CERROR("%s: invalid llog block at log id "DOSTID"/%u "
"offset "LPU64"\n",
o->do_lu.lo_dev->ld_obd->obd_name,
POSTID(&loghandle->lgh_id.lgl_oi),
loghandle->lgh_id.lgl_ogen, *cur_offset);
GOTO(out, rc = -EINVAL);
}
rec = buf;
if (LLOG_REC_HDR_NEEDS_SWABBING(rec))
lustre_swab_llog_rec(rec);
tail = (struct llog_rec_tail *)((char *)buf + rc -
sizeof(struct llog_rec_tail));
/* get the last record in block */
last_rec = (struct llog_rec_hdr *)((char *)buf + rc -
tail->lrt_len);
if (LLOG_REC_HDR_NEEDS_SWABBING(last_rec))
lustre_swab_llog_rec(last_rec);
LASSERT(last_rec->lrh_index == tail->lrt_index);
*cur_idx = tail->lrt_index;
/* this shouldn't happen */
if (tail->lrt_index == 0) {
CERROR("%s: invalid llog tail at log id "DOSTID"/%u "
"offset "LPU64"\n",
o->do_lu.lo_dev->ld_obd->obd_name,
POSTID(&loghandle->lgh_id.lgl_oi),
loghandle->lgh_id.lgl_ogen, *cur_offset);
GOTO(out, rc = -EINVAL);
}
if (tail->lrt_index < next_idx)
continue;
/* sanity check that the start of the new buffer is no farther
* than the record that we wanted. This shouldn't happen. */
if (rec->lrh_index > next_idx) {
CERROR("%s: missed desired record? %u > %u\n",
o->do_lu.lo_dev->ld_obd->obd_name,
rec->lrh_index, next_idx);
GOTO(out, rc = -ENOENT);
}
/* Trim unsupported extensions for compat w/ older clients */
if (!(loghandle->lgh_hdr->llh_flags & LLOG_F_EXT_JOBID))
changelog_block_trim_ext(rec, last_rec,
CLF_VERSION | CLF_RENAME);
GOTO(out, rc = 0);
}
GOTO(out, rc = -EIO);
out:
return rc;
}
