LU-16872 lod: reset llc_ostlist when using O_APPEND stripes

Files created with O_APPEND can have special striping set with the
parameters mdd.*.append_stripe_count and mdd.*.append_pool, and
should not inherit a list of OSTs to use from a parent directory
when these parameters are set. However, if a file is created with
O_APPEND and its create is handled by a kernel thread that has
previously created a file with a default list of OSTs, then those
defaults were erroneously applied to the O_APPEND file. This can
lead to the create returning EINVAL or to a crash.

This commit ensures that llc_ostlist is cleared when a file is
created with special append stripes.

Signed-off-by: Thomas Bertschinger <bertschinger@lanl.gov>
Change-Id: Ib2023e17c9ef31a2e029e09e67b257eb2c77b113
Reviewed-on: https://review.whamcloud.com/c/fs/lustre-release/+/51559
Tested-by: jenkins <devops@whamcloud.com>
Tested-by: Maloo <maloo@whamcloud.com>
Reviewed-by: Andreas Dilger <adilger@whamcloud.com>
Reviewed-by: Lai Siyao <lai.siyao@whamcloud.com>
Reviewed-by: Oleg Drokin <green@whamcloud.com>

diff --git a/lustre/lod/lod_object.c b/lustre/lod/lod_object.c
index 8a144e0..e6b4227 100644 (file)
--- a/lustre/lod/lod_object.c
+++ b/lustre/lod/lod_object.c
@@ -5418,9 +5418,9 @@ static int lod_get_default_lov_striping(const struct lu_env *env,
 
                lod_set_pool(&llc->llc_pool, pool);
 
-               if (append_stripe_count != 0 || append_pool != NULL) {
-                       /* Ignore specific striping for append. */
-               } else if (v1->lmm_magic == LOV_USER_MAGIC_SPECIFIC) {
+               if (v1->lmm_magic == LOV_USER_MAGIC_SPECIFIC &&
+                   append_stripe_count == 0 &&
+                   append_pool == NULL) {
                        v3 = (struct lov_user_md_v3 *)v1;
                        rc = lod_comp_copy_ost_lists(llc, v3);
                        if (rc)