From: Stephane Thiell <sthiell@stanford.edu>
Date: Thu, 11 Feb 2021 00:15:02 +0000 (-0800)
Subject: LU-13609 mgs: fix config_log buffer handling
X-Git-Tag: 2.12.7-RC1~35
X-Git-Url: https://git.whamcloud.com/?a=commitdiff_plain;h=refs%2Fchanges%2F77%2F41777%2F3;p=fs%2Flustre-release.git

LU-13609 mgs: fix config_log buffer handling

Fix buffer handling in mgs_list_logs() to list all MGS config_logs
using multiple ioctl calls when we have a large number of targets.

Lustre-change: https://review.whamcloud.com/41478
Lustre-commit: e3f17defc141d8847562b610931255d37ed4dd3c

Fixes: 1d97a8b4cd3d ("LU-13609 llog: list all the log files correctly on MGS/MDT")
Signed-off-by: Stephane Thiell <sthiell@stanford.edu>
Change-Id: I1bf32e918e242f4da83c3d1624b7285a18a88d01
Reviewed-by: Andreas Dilger <adilger@whamcloud.com>
Reviewed-by: Emoly Liu <emoly@whamcloud.com>
Signed-off-by: Minh Diep <mdiep@whamcloud.com>
Reviewed-on: https://review.whamcloud.com/41777
Tested-by: jenkins <devops@whamcloud.com>
Tested-by: Maloo <maloo@whamcloud.com>
Reviewed-by: Oleg Drokin <green@whamcloud.com>
---

diff --git a/lustre/mgs/mgs_llog.c b/lustre/mgs/mgs_llog.c
index 9c30a36..3fba4ad 100644
--- a/lustre/mgs/mgs_llog.c
+++ b/lustre/mgs/mgs_llog.c
@@ -4473,7 +4473,7 @@ int mgs_list_logs(const struct lu_env *env, struct mgs_device *mgs,
 	struct mgs_direntry	*dirent, *n;
 	char			*out, *suffix, prefix[] = "config_log: ";
 	int			 prefix_len = strlen(prefix);
-	int			 l, remains, start = 0, rc;
+	int			 len, remains, start = 0, rc;
 
 	ENTRY;
 
@@ -4492,8 +4492,8 @@ int mgs_list_logs(const struct lu_env *env, struct mgs_device *mgs,
 		list_del_init(&dirent->mde_list);
 		suffix = strrchr(dirent->mde_name, '-');
 		if (suffix != NULL) {
-			l = prefix_len + dirent->mde_len + 1;
-			if (remains - 1 < 0) {
+			len = prefix_len + dirent->mde_len + 1;
+			if (remains - len < 0) {
 				/* No enough space for this record */
 				mgs_direntry_free(dirent);
 				goto out;
@@ -4503,13 +4503,13 @@ int mgs_list_logs(const struct lu_env *env, struct mgs_device *mgs,
 				mgs_direntry_free(dirent);
 				continue;
 			}
-			l = scnprintf(out, remains, "%s%s\n", prefix,
-				     dirent->mde_name);
-			out += l;
-			remains -= l;
+			len = scnprintf(out, remains, "%s%s\n", prefix,
+					dirent->mde_name);
+			out += len;
+			remains -= len;
 		}
 		mgs_direntry_free(dirent);
-		if (remains == 0)
+		if (remains <= 1)
 			/* Full */
 			goto out;
 	}