diff options
| -rw-r--r-- | block/parallels.c | 33 |
1 files changed, 11 insertions, 22 deletions
diff --git a/block/parallels.c b/block/parallels.c index b2171016f1..efb6d4d6d4 100644 --- a/block/parallels.c +++ b/block/parallels.c @@ -83,7 +83,7 @@ static int parallels_open(BlockDriverState *bs, const char *filename, int flags) s->fd = fd; - if (read(fd, &ph, sizeof(ph)) != sizeof(ph)) + if (pread(fd, &ph, sizeof(ph), 0) != sizeof(ph)) goto fail; if (memcmp(ph.magic, HEADER_MAGIC, 16) || @@ -93,14 +93,11 @@ static int parallels_open(BlockDriverState *bs, const char *filename, int flags) bs->total_sectors = le32_to_cpu(ph.nb_sectors); - if (lseek(s->fd, 64, SEEK_SET) != 64) - goto fail; - s->tracks = le32_to_cpu(ph.tracks); s->catalog_size = le32_to_cpu(ph.catalog_entries); s->catalog_bitmap = qemu_malloc(s->catalog_size * 4); - if (read(s->fd, s->catalog_bitmap, s->catalog_size * 4) != + if (pread(s->fd, s->catalog_bitmap, s->catalog_size * 4, 64) != s->catalog_size * 4) goto fail; for (i = 0; i < s->catalog_size; i++) @@ -114,28 +111,18 @@ fail: return -1; } -static inline int seek_to_sector(BlockDriverState *bs, int64_t sector_num) +static int64_t seek_to_sector(BlockDriverState *bs, int64_t sector_num) { BDRVParallelsState *s = bs->opaque; uint32_t index, offset; - uint64_t position; index = sector_num / s->tracks; offset = sector_num % s->tracks; - // not allocated + /* not allocated */ if ((index > s->catalog_size) || (s->catalog_bitmap[index] == 0)) return -1; - - position = (uint64_t)(s->catalog_bitmap[index] + offset) * 512; - -// fprintf(stderr, "sector: %llx index=%x offset=%x pointer=%x position=%x\n", -// sector_num, index, offset, s->catalog_bitmap[index], position); - - if (lseek(s->fd, position, SEEK_SET) != position) - return -1; - - return 0; + return (uint64_t)(s->catalog_bitmap[index] + offset) * 512; } static int parallels_read(BlockDriverState *bs, int64_t sector_num, @@ -144,11 +131,13 @@ static int parallels_read(BlockDriverState *bs, int64_t sector_num, BDRVParallelsState *s = bs->opaque; while (nb_sectors > 0) { - if (!seek_to_sector(bs, sector_num)) { - if (read(s->fd, buf, 512) != 512) - return -1; - } else + int64_t position = seek_to_sector(bs, sector_num); + if (position >= 0) { + if (pread(s->fd, buf, 512, position) != 512) + return -1; + } else { memset(buf, 0, 512); + } nb_sectors--; sector_num++; buf += 512; |