[dhowells-fs:netfs-folio-regions 23/28] fs/netfs/write_back.c:1071:1: error: expected statement

From: kernel test robot
Date: Thu Aug 19 2021 - 16:48:44 EST

tree: https://git.kernel.org/pub/scm/linux/kernel/git/dhowells/linux-fs.git netfs-folio-regions
head: 215a4ee495a95cc73256ed76f91cb78bcabd6b8e
commit: 763245c0c72ba51e185586cdaa4646b49ba7f14c [23/28] netfs: Pass initial write into netfs_flush_dirty()
config: hexagon-randconfig-r041-20210818 (attached as .config)
compiler: clang version 12.0.0
reproduce (this is a W=1 build):
wget https://raw.githubusercontent.com/intel/lkp-tests/master/sbin/make.cross -O ~/bin/make.cross
chmod +x ~/bin/make.cross
# https://git.kernel.org/pub/scm/linux/kernel/git/dhowells/linux-fs.git/commit/?id=763245c0c72ba51e185586cdaa4646b49ba7f14c
git remote add dhowells-fs https://git.kernel.org/pub/scm/linux/kernel/git/dhowells/linux-fs.git
git fetch --no-tags dhowells-fs netfs-folio-regions
git checkout 763245c0c72ba51e185586cdaa4646b49ba7f14c
# save the attached .config to linux build tree
mkdir build_dir
COMPILER_INSTALL_PATH=$HOME/0day COMPILER=clang make.cross O=build_dir ARCH=hexagon SHELL=/bin/bash fs/netfs/

If you fix the issue, kindly add following tag as appropriate
Reported-by: kernel test robot <lkp@xxxxxxxxx>

All errors (new ones prefixed by >>):

fs/netfs/write_back.c:108:22: warning: variable 'region' is uninitialized when used here [-Wuninitialized]
if (within(&range, &region->dirty)) {
^~~~~~
fs/netfs/write_back.c:98:35: note: initialize the variable 'region' to silence this warning
struct netfs_dirty_region *region, *r;
^
= NULL
fs/netfs/write_back.c:438:7: warning: variable 'ret' is used uninitialized whenever 'if' condition is false [-Wsometimes-uninitialized]
if (!folio_trylock(folio))
^~~~~~~~~~~~~~~~~~~~~
fs/netfs/write_back.c:442:9: note: uninitialized use occurs here
return ret;
^~~
fs/netfs/write_back.c:438:3: note: remove the 'if' if its condition is always true
if (!folio_trylock(folio))
^~~~~~~~~~~~~~~~~~~~~~~~~~
fs/netfs/write_back.c:425:9: note: initialize the variable 'ret' to silence this warning
int ret;
^
= 0
fs/netfs/write_back.c:492:22: warning: variable 'region' is uninitialized when used here [-Wuninitialized]
if (within(&range, &region->dirty))
^~~~~~
fs/netfs/write_back.c:481:35: note: initialize the variable 'region' to silence this warning
struct netfs_dirty_region *region, *r;
^
= NULL
>> fs/netfs/write_back.c:1071:1: error: expected statement
}
^
3 warnings and 1 error generated.


vim +1071 fs/netfs/write_back.c

763245c0c72ba5 David Howells 2021-08-02 976
763245c0c72ba5 David Howells 2021-08-02 977 /*
763245c0c72ba5 David Howells 2021-08-02 978 * Flush from the front group in the flush FIFO.
763245c0c72ba5 David Howells 2021-08-02 979 */
763245c0c72ba5 David Howells 2021-08-02 980 static int netfs_flush_group(struct address_space *mapping, bool may_wait)
763245c0c72ba5 David Howells 2021-08-02 981 {
763245c0c72ba5 David Howells 2021-08-02 982 struct netfs_write_request *wreq = NULL;
763245c0c72ba5 David Howells 2021-08-02 983 struct netfs_dirty_region *spares[2] = {}, *head, *r, *wait_for;
763245c0c72ba5 David Howells 2021-08-02 984 struct netfs_flush_group *group;
763245c0c72ba5 David Howells 2021-08-02 985 struct netfs_i_context *ctx = netfs_i_context(mapping->host);
763245c0c72ba5 David Howells 2021-08-02 986 struct netfs_range range;
763245c0c72ba5 David Howells 2021-08-02 987 unsigned int min_bsize = 1U << ctx->min_bshift;
763245c0c72ba5 David Howells 2021-08-02 988 loff_t wait_to;
763245c0c72ba5 David Howells 2021-08-02 989 int ret;
763245c0c72ba5 David Howells 2021-08-02 990
763245c0c72ba5 David Howells 2021-08-02 991 kenter("");
763245c0c72ba5 David Howells 2021-08-02 992
763245c0c72ba5 David Howells 2021-08-02 993 ret = netfs_sanity_check_ictx(mapping);
763245c0c72ba5 David Howells 2021-08-02 994 if (ret < 0)
763245c0c72ba5 David Howells 2021-08-02 995 return ret;
763245c0c72ba5 David Howells 2021-08-02 996
763245c0c72ba5 David Howells 2021-08-02 997 retry:
763245c0c72ba5 David Howells 2021-08-02 998 if (!wreq) {
763245c0c72ba5 David Howells 2021-08-02 999 ret = -ENOMEM;
763245c0c72ba5 David Howells 2021-08-02 1000 wreq = netfs_alloc_write_request(mapping, false);
763245c0c72ba5 David Howells 2021-08-02 1001 if (!wreq)
763245c0c72ba5 David Howells 2021-08-02 1002 goto out_unlocked;
763245c0c72ba5 David Howells 2021-08-02 1003 }
1e4f2a70cbedd7 David Howells 2021-07-29 1004
763245c0c72ba5 David Howells 2021-08-02 1005 spin_lock(&ctx->lock);
763245c0c72ba5 David Howells 2021-08-02 1006
763245c0c72ba5 David Howells 2021-08-02 1007 group = list_first_entry(&ctx->flush_groups, struct netfs_flush_group, group_link);
763245c0c72ba5 David Howells 2021-08-02 1008 if (list_empty(&group->region_list))
763245c0c72ba5 David Howells 2021-08-02 1009 goto group_empty;
763245c0c72ba5 David Howells 2021-08-02 1010
763245c0c72ba5 David Howells 2021-08-02 1011 /* We take the first region on the list as a starting point */
763245c0c72ba5 David Howells 2021-08-02 1012 head = list_first_entry(&group->region_list, struct netfs_dirty_region, flush_link);
763245c0c72ba5 David Howells 2021-08-02 1013 range.start = round_down(head->dirty.start, min_bsize);
763245c0c72ba5 David Howells 2021-08-02 1014 range.end = (unsigned long long)LLONG_MAX + 1;
763245c0c72ba5 David Howells 2021-08-02 1015 kdebug("query D=%x", r->debug_id);
763245c0c72ba5 David Howells 2021-08-02 1016
763245c0c72ba5 David Howells 2021-08-02 1017 ret = netfs_flush_dirty(ctx, head, spares, &range, wreq, &wait_for, &wait_to);
763245c0c72ba5 David Howells 2021-08-02 1018 switch (ret) {
763245c0c72ba5 David Howells 2021-08-02 1019 case -ENOBUFS:
763245c0c72ba5 David Howells 2021-08-02 1020 spin_unlock(&ctx->lock);
763245c0c72ba5 David Howells 2021-08-02 1021 goto need_spares;
763245c0c72ba5 David Howells 2021-08-02 1022 case -EAGAIN:
763245c0c72ba5 David Howells 2021-08-02 1023 if (wait_for)
763245c0c72ba5 David Howells 2021-08-02 1024 goto wait_for_active_region;
763245c0c72ba5 David Howells 2021-08-02 1025 spin_unlock(&ctx->lock);
763245c0c72ba5 David Howells 2021-08-02 1026 goto retry;
763245c0c72ba5 David Howells 2021-08-02 1027 default:
763245c0c72ba5 David Howells 2021-08-02 1028 spin_unlock(&ctx->lock);
763245c0c72ba5 David Howells 2021-08-02 1029 goto out_unlocked;
763245c0c72ba5 David Howells 2021-08-02 1030 case 0:
763245c0c72ba5 David Howells 2021-08-02 1031 spin_unlock(&ctx->lock);
763245c0c72ba5 David Howells 2021-08-02 1032 break;
763245c0c72ba5 David Howells 2021-08-02 1033 }
763245c0c72ba5 David Howells 2021-08-02 1034
763245c0c72ba5 David Howells 2021-08-02 1035 /* TODO: Flush more pieces */
763245c0c72ba5 David Howells 2021-08-02 1036
763245c0c72ba5 David Howells 2021-08-02 1037 out_unlocked:
763245c0c72ba5 David Howells 2021-08-02 1038 netfs_free_dirty_region(ctx, spares[0]);
763245c0c72ba5 David Howells 2021-08-02 1039 netfs_free_dirty_region(ctx, spares[1]);
763245c0c72ba5 David Howells 2021-08-02 1040 netfs_put_write_request(wreq, false, netfs_wreq_trace_put_discard);
763245c0c72ba5 David Howells 2021-08-02 1041 return ret;
763245c0c72ba5 David Howells 2021-08-02 1042
763245c0c72ba5 David Howells 2021-08-02 1043 wait_for_active_region:
763245c0c72ba5 David Howells 2021-08-02 1044 if (!may_wait)
763245c0c72ba5 David Howells 2021-08-02 1045 return -EBUSY;
763245c0c72ba5 David Howells 2021-08-02 1046
763245c0c72ba5 David Howells 2021-08-02 1047 if (!spares[0] || !spares[1])
763245c0c72ba5 David Howells 2021-08-02 1048 return -ENOBUFS;
763245c0c72ba5 David Howells 2021-08-02 1049
763245c0c72ba5 David Howells 2021-08-02 1050 netfs_get_dirty_region(ctx, r, netfs_region_trace_get_wait_active);
763245c0c72ba5 David Howells 2021-08-02 1051 spin_unlock(&ctx->lock);
763245c0c72ba5 David Howells 2021-08-02 1052
763245c0c72ba5 David Howells 2021-08-02 1053 wait_var_event(&r->state, (READ_ONCE(r->state) != NETFS_REGION_IS_ACTIVE ||
763245c0c72ba5 David Howells 2021-08-02 1054 READ_ONCE(r->dirty.end) != wait_to));
763245c0c72ba5 David Howells 2021-08-02 1055 netfs_put_dirty_region(ctx, r, netfs_region_trace_put_wait_active);
1e4f2a70cbedd7 David Howells 2021-07-29 1056 need_spares:
1e4f2a70cbedd7 David Howells 2021-07-29 1057 ret = -ENOMEM;
763245c0c72ba5 David Howells 2021-08-02 1058 if (!spares[0]) {
1e4f2a70cbedd7 David Howells 2021-07-29 1059 spares[0] = netfs_alloc_dirty_region();
1e4f2a70cbedd7 David Howells 2021-07-29 1060 if (!spares[0])
1e4f2a70cbedd7 David Howells 2021-07-29 1061 goto out_unlocked;
763245c0c72ba5 David Howells 2021-08-02 1062 }
763245c0c72ba5 David Howells 2021-08-02 1063 if (!spares[1]) {
1e4f2a70cbedd7 David Howells 2021-07-29 1064 spares[1] = netfs_alloc_dirty_region();
1e4f2a70cbedd7 David Howells 2021-07-29 1065 if (!spares[1])
1e4f2a70cbedd7 David Howells 2021-07-29 1066 goto out_unlocked;
763245c0c72ba5 David Howells 2021-08-02 1067 }
1e4f2a70cbedd7 David Howells 2021-07-29 1068 goto retry;
763245c0c72ba5 David Howells 2021-08-02 1069
763245c0c72ba5 David Howells 2021-08-02 1070 group_empty:
1e4f2a70cbedd7 David Howells 2021-07-29 @1071 }
1e4f2a70cbedd7 David Howells 2021-07-29 1072

:::::: The code at line 1071 was first introduced by commit
:::::: 1e4f2a70cbedd75d80440425727faa78e2dccb93 netfs: Cut out region to be written from dirty regions

:::::: TO: David Howells <dhowells@xxxxxxxxxx>
:::::: CC: David Howells <dhowells@xxxxxxxxxx>

---
0-DAY CI Kernel Test Service, Intel Corporation
https://lists.01.org/hyperkitty/list/kbuild-all@xxxxxxxxxxxx

Attachment: .config.gz
Description: application/gzip