diff options
Diffstat (limited to 'block')
-rw-r--r-- | block/file-posix.c | 54 |
1 files changed, 28 insertions, 26 deletions
diff --git a/block/file-posix.c b/block/file-posix.c index ab05b51a66..4479cc7ab4 100644 --- a/block/file-posix.c +++ b/block/file-posix.c @@ -1038,15 +1038,13 @@ static void raw_reopen_abort(BDRVReopenState *state) s->reopen_state = NULL; } -static int hdev_get_max_transfer_length(BlockDriverState *bs, int fd) +static int sg_get_max_transfer_length(int fd) { #ifdef BLKSECTGET int max_bytes = 0; - short max_sectors = 0; - if (bs->sg && ioctl(fd, BLKSECTGET, &max_bytes) == 0) { + + if (ioctl(fd, BLKSECTGET, &max_bytes) == 0) { return max_bytes; - } else if (!bs->sg && ioctl(fd, BLKSECTGET, &max_sectors) == 0) { - return max_sectors << BDRV_SECTOR_BITS; } else { return -errno; } @@ -1055,25 +1053,31 @@ static int hdev_get_max_transfer_length(BlockDriverState *bs, int fd) #endif } -static int hdev_get_max_segments(const struct stat *st) +static int sg_get_max_segments(int fd) { #ifdef CONFIG_LINUX char buf[32]; const char *end; - char *sysfspath; + char *sysfspath = NULL; int ret; - int fd = -1; + int sysfd = -1; long max_segments; + struct stat st; + + if (fstat(fd, &st)) { + ret = -errno; + goto out; + } sysfspath = g_strdup_printf("/sys/dev/block/%u:%u/queue/max_segments", - major(st->st_rdev), minor(st->st_rdev)); - fd = open(sysfspath, O_RDONLY); - if (fd == -1) { + major(st.st_rdev), minor(st.st_rdev)); + sysfd = open(sysfspath, O_RDONLY); + if (sysfd == -1) { ret = -errno; goto out; } do { - ret = read(fd, buf, sizeof(buf) - 1); + ret = read(sysfd, buf, sizeof(buf) - 1); } while (ret == -1 && errno == EINTR); if (ret < 0) { ret = -errno; @@ -1090,8 +1094,8 @@ static int hdev_get_max_segments(const struct stat *st) } out: - if (fd != -1) { - close(fd); + if (sysfd != -1) { + close(sysfd); } g_free(sysfspath); return ret; @@ -1103,19 +1107,17 @@ out: static void raw_refresh_limits(BlockDriverState *bs, Error **errp) { BDRVRawState *s = bs->opaque; - struct stat st; - if (!fstat(s->fd, &st)) { - if (S_ISBLK(st.st_mode) || S_ISCHR(st.st_mode)) { - int ret = hdev_get_max_transfer_length(bs, s->fd); - if (ret > 0 && ret <= BDRV_REQUEST_MAX_BYTES) { - bs->bl.max_transfer = pow2floor(ret); - } - ret = hdev_get_max_segments(&st); - if (ret > 0) { - bs->bl.max_transfer = MIN(bs->bl.max_transfer, - ret * getpagesize()); - } + if (bs->sg) { + int ret = sg_get_max_transfer_length(s->fd); + + if (ret > 0 && ret <= BDRV_REQUEST_MAX_BYTES) { + bs->bl.max_transfer = pow2floor(ret); + } + + ret = sg_get_max_segments(s->fd); + if (ret > 0) { + bs->bl.max_transfer = MIN(bs->bl.max_transfer, ret * getpagesize()); } } |