From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from eggs.gnu.org ([208.118.235.92]:52652) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1SoWVc-0002MR-85 for qemu-devel@nongnu.org; Tue, 10 Jul 2012 05:13:36 -0400 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1SoWVU-0002MW-Lh for qemu-devel@nongnu.org; Tue, 10 Jul 2012 05:13:27 -0400 Received: from oxygen.pond.sub.org ([78.46.104.156]:57861) by eggs.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1SoWVU-0002M8-FH for qemu-devel@nongnu.org; Tue, 10 Jul 2012 05:13:20 -0400 From: Markus Armbruster Date: Tue, 10 Jul 2012 11:12:28 +0200 Message-Id: <1341911575-7306-3-git-send-email-armbru@redhat.com> In-Reply-To: <1341911575-7306-1-git-send-email-armbru@redhat.com> References: <1341911575-7306-1-git-send-email-armbru@redhat.com> Subject: [Qemu-devel] [PATCH v3 02/29] vvfat: Fix partition table List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , To: qemu-devel@nongnu.org Cc: kwolf@redhat.com, blauwirbel@gmail.com, stefanha@linux.vnet.ibm.com, pbonzini@redhat.com Unless parameter ":floppy:" is given, vvfat creates a virtual image with DOS MBR defining a single partition which holds the FAT file system. The size of the virtual image depends on the width of the FAT: 32 MiB (CHS 64, 16, 63) for 12 bit FAT, 504 MiB (CHS 1024, 16, 63) for 16 and 32 bit FAT, leaving (64*16-1)*63 = 64449 and (1024*16-1)*64 = 1032129 sectors for the partition. However, it screws up the end of the partition in the MBR: FAT width param. start CHS end CHS start LBA size :32: 0,1,1 1023,14,63 63 1032065 :16: 0,1,1 1023,14,55 63 1032057 :12: 0,1,1 63,14,55 63 64377 The actual FAT file system nevertheless assumes the partition has 1032129 or 64449 sectors. Oops. Signed-off-by: Markus Armbruster --- block/vvfat.c | 7 ++++--- 1 files changed, 4 insertions(+), 3 deletions(-) diff --git a/block/vvfat.c b/block/vvfat.c index 0fd3367..e2b83a2 100644 --- a/block/vvfat.c +++ b/block/vvfat.c @@ -394,11 +394,12 @@ static void init_mbr(BDRVVVFATState* s) /* LBA is used when partition is outside the CHS geometry */ lba = sector2CHS(s->bs, &partition->start_CHS, s->first_sectors_number-1); - lba|= sector2CHS(s->bs, &partition->end_CHS, s->sector_count); + lba |= sector2CHS(s->bs, &partition->end_CHS, s->bs->total_sectors - 1); /*LBA partitions are identified only by start/length_sector_long not by CHS*/ - partition->start_sector_long =cpu_to_le32(s->first_sectors_number-1); - partition->length_sector_long=cpu_to_le32(s->sector_count - s->first_sectors_number+1); + partition->start_sector_long = cpu_to_le32(s->first_sectors_number - 1); + partition->length_sector_long = cpu_to_le32(s->bs->total_sectors + - s->first_sectors_number + 1); /* FAT12/FAT16/FAT32 */ /* DOS uses different types when partition is LBA, -- 1.7.6.5