+
+/**** Changelogs *****/
+#define D_CHANGELOG 0
+
+DECLARE_CHANGELOG_NAMES;
+
+/* How many records per seq_show. Too small, we spawn llog_process threads
+ too often; too large, we run out of buffer space */
+#define CHANGELOG_CHUNK_SIZE 100
+
+static int changelog_show_cb(struct llog_handle *llh, struct llog_rec_hdr *hdr,
+ void *data)
+{
+ struct seq_file *seq = (struct seq_file *)data;
+ struct changelog_seq_iter *csi = seq->private;
+ struct llog_changelog_rec *rec = (struct llog_changelog_rec *)hdr;
+ int rc;
+ ENTRY;
+
+ if ((rec->cr_hdr.lrh_type != CHANGELOG_REC) ||
+ (rec->cr_type >= CL_LAST)) {
+ CERROR("Not a changelog rec %d/%d\n", rec->cr_hdr.lrh_type,
+ rec->cr_type);
+ RETURN(-EINVAL);
+ }
+
+ CDEBUG(D_CHANGELOG, "rec="LPU64" start="LPU64" cat=%d:%d start=%d:%d\n",
+ rec->cr_index, csi->csi_startrec,
+ llh->lgh_hdr->llh_cat_idx, llh->lgh_cur_idx,
+ csi->csi_startcat, csi->csi_startidx);
+
+ if (rec->cr_index < csi->csi_startrec)
+ /* Skip entries earlier than what we are interested in */
+ RETURN(0);
+ if (rec->cr_index == csi->csi_startrec) {
+ /* Remember where we started, since seq_read will re-read
+ * the data when it reallocs space. Sigh, if only there was
+ * a way to tell seq_file how big the buf should be in the
+ * first place...
+ */
+ csi->csi_startcat = llh->lgh_hdr->llh_cat_idx;
+ csi->csi_startidx = rec->cr_hdr.lrh_index - 1;
+ }
+ if (csi->csi_wrote > CHANGELOG_CHUNK_SIZE) {
+ /* Stop at some point with a reasonable seq_file buffer size.
+ * Start from here the next time.
+ */
+ csi->csi_endrec = rec->cr_index - 1;
+ csi->csi_startcat = llh->lgh_hdr->llh_cat_idx;
+ csi->csi_startidx = rec->cr_hdr.lrh_index - 1;
+ csi->csi_wrote = 0;
+ RETURN(LLOG_PROC_BREAK);
+ }
+
+ rc = seq_printf(seq, LPU64" %02d%-5s "LPU64" 0x%x t="DFID,
+ rec->cr_index, rec->cr_type,
+ changelog_str[rec->cr_type], rec->cr_time,
+ rec->cr_flags & CLF_FLAGMASK, PFID(&rec->cr_tfid));
+
+ if (rec->cr_namelen)
+ /* namespace rec includes parent and filename */
+ rc += seq_printf(seq, " p="DFID" %.*s\n", PFID(&rec->cr_pfid),
+ rec->cr_namelen, rec->cr_name);
+ else
+ rc += seq_puts(seq, "\n");
+
+ if (rc < 0) {
+ /* Ran out of room in the seq buffer. seq_read will dump
+ * the whole buffer and re-seq_start with a larger one;
+ * no point in continuing the llog_process */
+ CDEBUG(D_CHANGELOG, "rec="LPU64" overflow "LPU64"<-"LPU64"\n",
+ rec->cr_index, csi->csi_startrec, csi->csi_endrec);
+ csi->csi_endrec = csi->csi_startrec - 1;
+ csi->csi_wrote = 0;
+ RETURN(LLOG_PROC_BREAK);
+ }
+
+ csi->csi_wrote++;
+ csi->csi_endrec = rec->cr_index;
+
+ RETURN(0);
+}
+
+static int changelog_seq_show(struct seq_file *seq, void *v)
+{
+ struct changelog_seq_iter *csi = seq->private;
+ int rc;
+ ENTRY;
+
+ if (csi->csi_fill) {
+ /* seq_read wants more data to fill his buffer. But we already
+ filled the buf as much as we cared to; force seq_read to
+ accept that by padding with 0's */
+ while (seq_putc(seq, 0) == 0);
+ RETURN(0);
+ }
+
+ /* Since we have to restart the llog_cat_process for each chunk of the
+ seq_ functions, start from where we left off. */
+ rc = llog_cat_process(csi->csi_llh, changelog_show_cb, seq,
+ csi->csi_startcat, csi->csi_startidx);
+
+ CDEBUG(D_CHANGELOG,"seq_show "LPU64"-"LPU64" cat=%d:%d wrote=%d rc=%d\n",
+ csi->csi_startrec, csi->csi_endrec, csi->csi_startcat,
+ csi->csi_startidx, csi->csi_wrote, rc);
+
+ if (rc == 0)
+ csi->csi_done = 1;
+ if (rc == LLOG_PROC_BREAK)
+ /* more records left, but seq_show must return 0 */
+ rc = 0;
+ RETURN(rc);
+}
+
+static void *changelog_seq_start(struct seq_file *seq, loff_t *pos)
+{
+ struct changelog_seq_iter *csi = seq->private;
+ LASSERT(csi);
+
+ CDEBUG(D_CHANGELOG, "start "LPU64"-"LPU64" pos="LPU64"\n",
+ csi->csi_startrec, csi->csi_endrec, *pos);
+
+ csi->csi_fill = 0;
+
+ if (csi->csi_done)
+ /* no more records, seq_read should return 0 if buffer
+ is empty */
+ return NULL;
+
+ if (*pos > csi->csi_pos) {
+ /* The seq_read implementation sucks. It may call start
+ multiple times, using pos to indicate advances, if any,
+ by arbitrarily increasing it by 1. So ignore the actual
+ value of pos, and just register any increase as
+ "seq_read wants the next values". */
+ csi->csi_startrec = csi->csi_endrec + 1;
+ csi->csi_pos = *pos;
+ }
+ /* else use old startrec/startidx */
+
+ return csi;
+}
+
+static void changelog_seq_stop(struct seq_file *seq, void *v)
+{
+ struct changelog_seq_iter *csi = seq->private;
+
+ CDEBUG(D_CHANGELOG, "stop "LPU64"-"LPU64"\n",
+ csi->csi_startrec, csi->csi_endrec);
+}
+
+static void *changelog_seq_next(struct seq_file *seq, void *v, loff_t *pos)
+{
+ struct changelog_seq_iter *csi = seq->private;
+
+ CDEBUG(D_CHANGELOG, "next "LPU64"-"LPU64" pos="LPU64"\n",
+ csi->csi_startrec, csi->csi_endrec, *pos);
+
+ csi->csi_fill = 1;
+
+ return csi;
+}
+
+static struct seq_operations changelog_sops = {
+ .start = changelog_seq_start,
+ .stop = changelog_seq_stop,
+ .next = changelog_seq_next,
+ .show = changelog_seq_show,
+};
+
+int changelog_seq_open(struct inode *inode, struct file *file,
+ struct changelog_seq_iter **csih)
+{
+ struct changelog_seq_iter *csi;
+ struct proc_dir_entry *dp = PDE(inode);
+ struct seq_file *seq;
+ int rc;
+
+ LPROCFS_ENTRY_AND_CHECK(dp);
+
+ rc = seq_open(file, &changelog_sops);
+ if (rc) {
+ LPROCFS_EXIT();
+ return rc;
+ }
+
+ OBD_ALLOC_PTR(csi);
+ if (csi == NULL) {
+ lprocfs_seq_release(inode, file);
+ return -ENOMEM;
+ }
+
+ csi->csi_dev = dp->data;
+ seq = file->private_data;
+ seq->private = csi;
+ *csih = csi;
+
+ return rc;
+}
+EXPORT_SYMBOL(changelog_seq_open);
+
+int changelog_seq_release(struct inode *inode, struct file *file)
+{
+ struct seq_file *seq = file->private_data;
+ struct changelog_seq_iter *csi = seq->private;
+
+ if (csi)
+ OBD_FREE_PTR(csi);
+
+ return lprocfs_seq_release(inode, file);
+}
+EXPORT_SYMBOL(changelog_seq_release);
+
+loff_t changelog_seq_lseek(struct file *file, loff_t offset, int origin)
+{
+ struct seq_file *seq = (struct seq_file *)file->private_data;
+ struct changelog_seq_iter *csi = seq->private;
+
+ CDEBUG(D_CHANGELOG,"seek "LPU64"-"LPU64" off="LPU64":%d fpos="LPU64"\n",
+ csi->csi_startrec, csi->csi_endrec, offset, origin, file->f_pos);
+
+ LL_SEQ_LOCK(seq);
+
+ switch (origin) {
+ case SEEK_CUR:
+ offset += csi->csi_endrec;
+ break;
+ case SEEK_END:
+ /* we don't know the last rec */
+ offset = -1;
+ }
+
+ /* SEEK_SET */
+
+ if (offset < 0) {
+ LL_SEQ_UNLOCK(seq);
+ return -EINVAL;
+ }
+
+ csi->csi_startrec = offset;
+ csi->csi_endrec = offset ? offset - 1 : 0;
+
+ /* drop whatever is left in sucky seq_read's buffer */
+ seq->count = 0;
+ seq->from = 0;
+ seq->index++;
+ LL_SEQ_UNLOCK(seq);
+ file->f_pos = csi->csi_startrec;
+ return csi->csi_startrec;
+}
+EXPORT_SYMBOL(changelog_seq_lseek);
+
git://git.whamcloud.com / fs / lustre-release.git / commitdiff