diff options
author | David Teigland <teigland@redhat.com> | 2018-11-16 13:09:29 -0600 |
---|---|---|
committer | David Teigland <teigland@redhat.com> | 2018-11-20 09:04:37 -0600 |
commit | cb5405ded86209979eef54433d0b90942b2f976a (patch) | |
tree | 239ddbecd16336468681acd8c90c448116e504cd | |
parent | f8ce9bf3bc38df8f89021517d7967d94ace129df (diff) | |
download | lvm2-cb5405ded86209979eef54433d0b90942b2f976a.tar.gz |
bcache: sync io fixes
fix lseek error check
fix read/write error checks
handle zero return from read and write
don't return an error for short io
fix partial read/write loop
-rw-r--r-- | lib/device/bcache.c | 69 |
1 files changed, 47 insertions, 22 deletions
diff --git a/lib/device/bcache.c b/lib/device/bcache.c index 571ee7a2b..7384a3290 100644 --- a/lib/device/bcache.c +++ b/lib/device/bcache.c @@ -328,7 +328,7 @@ struct io_engine *create_async_io_engine(void) e->aio_context = 0; r = io_setup(MAX_IO, &e->aio_context); if (r < 0) { - log_warn("io_setup failed"); + log_debug("io_setup failed %d", r); dm_free(e); return NULL; } @@ -371,8 +371,11 @@ static void _sync_destroy(struct io_engine *ioe) static bool _sync_issue(struct io_engine *ioe, enum dir d, int fd, sector_t sb, sector_t se, void *data, void *context) { - int r; - uint64_t len = (se - sb) * 512, where; + int rv; + off_t off; + uint64_t where; + uint64_t pos = 0; + uint64_t len = (se - sb) * 512; struct sync_engine *e = _to_sync(ioe); struct sync_io *io = malloc(sizeof(*io)); if (!io) { @@ -381,11 +384,17 @@ static bool _sync_issue(struct io_engine *ioe, enum dir d, int fd, } where = sb * 512; - r = lseek(fd, where, SEEK_SET); - if (r < 0) { - log_warn("unable to seek to position %llu", (unsigned long long) where); - free(io); - return false; + + off = lseek(fd, where, SEEK_SET); + if (off == (off_t) -1) { + log_warn("Device seek error %d for offset %llu", errno, (unsigned long long)where); + free(io); + return false; + } + if (off != (off_t) where) { + log_warn("Device seek failed for offset %llu", (unsigned long long)where); + free(io); + return false; } /* @@ -430,28 +439,44 @@ static bool _sync_issue(struct io_engine *ioe, enum dir d, int fd, len = nbytes; } - while (len) { - do { - if (d == DIR_READ) - r = read(fd, data, len); - else - r = write(fd, data, len); + while (pos < len) { + if (d == DIR_READ) + rv = read(fd, (char *)data + pos, len - pos); + else + rv = write(fd, (char *)data + pos, len - pos); - } while ((r < 0) && ((r == EINTR) || (r == EAGAIN))); + if (rv == -1 && errno == EINTR) + continue; + if (rv == -1 && errno == EAGAIN) + continue; + + if (!rv) + break; - if (r < 0) { - log_warn("io failed %d", r); + if (rv < 0) { + if (d == DIR_READ) + log_debug("Device read error %d offset %llu len %llu", errno, + (unsigned long long)(where + pos), + (unsigned long long)(len - pos)); + else + log_debug("Device write error %d offset %llu len %llu", errno, + (unsigned long long)(where + pos), + (unsigned long long)(len - pos)); free(io); return false; - } - - len -= r; + } + pos += rv; } - if (len) { - log_warn("short io %u bytes remaining", (unsigned) len); + if (pos < len) { + if (d == DIR_READ) + log_warn("Device read short %u bytes remaining", (unsigned)(len - pos)); + else + log_warn("Device write short %u bytes remaining", (unsigned)(len - pos)); + /* free(io); return false; + */ } |