Re: [libvirt] [PATCH] safezero: fall back to writing zeroes even when resizing

Remove the resize flag and use the same code path for all callers. This flag was added by commit 18f0316 to allow virStorageFileResize use 'safezero' while preserving the behavior. Explicitly return -2 when a fallback to a different method should be done, to make the code path more obvious. Fail immediately when ftruncate fails in the mmap method, as we did before commit 18f0316. --- src/locking/lock_driver_sanlock.c | 4 ++-- src/storage/storage_backend.c | 2 +- src/util/virfile.c | 34 ++++++++++++---------------------- src/util/virfile.h | 2 +- src/util/virstoragefile.c | 13 ++++--------- 5 files changed, 20 insertions(+), 35 deletions(-)

diff --git a/src/util/virfile.c b/src/util/virfile.c index a2bf008..5f56005 100644 --- a/src/util/virfile.c +++ b/src/util/virfile.c

-int safezero(int fd, off_t offset, off_t len, bool resize) +int safezero(int fd, off_t offset, off_t len) { int ret; - /* posix_fallocate returns 0 on success or error number on failure, - * but errno is not set so use that to our advantage since we set - * errno to the returned value if we make the call. If we don't make - * the call because it doesn't exist, then errno won't change and - * we can try other methods. - */ - errno = 0; ret = safezero_posix_fallocate(fd, offset, len); - if (ret == 0 || errno != 0) + if (ret != -2) return ret; - if (resize) - return safezero_sys_fallocate(fd, offset, len); - - if (safezero_mmap(fd, offset, len) == 0) + if (safezero_sys_fallocate(fd, offset, len) == 0) return 0;

+ + ret = safezero_mmap(fd, offset, len); + if (ret != -2) + return ret; return safezero_slow(fd, offset, len); }