File efibootmgr-0.5.4-sector-size.diff of Package efibootmgr
From b8af2c229031e274a2c61293a1a634e515a56d27 Mon Sep 17 00:00:00 2001
In-Reply-To: <1279121617-17961-1-git-send-email-pjones@redhat.com>
References: <1279121617-17961-1-git-send-email-pjones@redhat.com>
From: Peter Jones <pjones@redhat.com>
Date: Wed, 14 Jul 2010 14:55:17 -0400
Subject: [efibootmgr patch] Handle sector_size != 512.
Disks can have 4kB sectors now, so don't just bail out when that's the
case.
---
src/include/disk.h | 3 +++
src/lib/disk.c | 42 ++++++++++++++++++++++++++++++++----------
src/lib/gpt.c | 24 +++++++++++-------------
3 files changed, 46 insertions(+), 23 deletions(-)
--- a/src/include/disk.h
+++ b/src/include/disk.h
@@ -65,6 +65,9 @@ enum _interface_type {interface_type_unk
ata, atapi, scsi, usb,
i1394, fibre, i2o, md};
+
+unsigned int lcm(unsigned int x, unsigned int y);
+
int disk_get_pci(int fd,
unsigned char *bus,
unsigned char *device,
--- a/src/lib/disk.c
+++ b/src/lib/disk.c
@@ -420,6 +420,27 @@ get_sector_size(int filedes)
return sector_size;
}
+/************************************************************
+ * lcm
+ * Requires:
+ * - numbers of which to find the lowest common multiple
+ * Modifies: nothing
+ * Returns:
+ * lowest common multiple of x and y
+ ************************************************************/
+unsigned int
+lcm(unsigned int x, unsigned int y)
+{
+ unsigned int m = x, n = y, o;
+
+ while ((o = m % n)) {
+ m = n;
+ n = o;
+ }
+
+ return (x / n) * y;
+}
+
/**
* disk_get_partition_info()
* @fd - open file descriptor to disk
@@ -442,26 +463,26 @@ disk_get_partition_info (int fd,
uint8_t *mbr_type, uint8_t *signature_type)
{
legacy_mbr *mbr;
- void *mbr_unaligned;
+ void *mbr_sector;
+ size_t mbr_size;
off_t offset;
int this_bytes_read = 0;
int gpt_invalid=0, mbr_invalid=0;
int rc=0;
int sector_size = get_sector_size(fd);
- if (sizeof(*mbr) != sector_size)
- return 1;
- mbr_unaligned = malloc(sizeof(*mbr)+sector_size-1);
- mbr = (legacy_mbr *)
- (((unsigned long)mbr_unaligned + sector_size - 1) &
- ~(unsigned long)(sector_size-1));
- memset(mbr, 0, sizeof(*mbr));
+ mbr_size = lcm(sizeof(*mbr), sector_size);
+ if ((rc = posix_memalign(&mbr_sector, sector_size, mbr_size)) != 0)
+ goto error;
+ memset(mbr_sector, '\0', mbr_size);
+
offset = lseek(fd, 0, SEEK_SET);
- this_bytes_read = read(fd, mbr, sizeof(*mbr));
+ this_bytes_read = read(fd, mbr_sector, mbr_size);
if (this_bytes_read < sizeof(*mbr)) {
rc=1;
goto error_free_mbr;
}
+ mbr = (legacy_mbr *)mbr_sector;
gpt_invalid = gpt_disk_get_partition_info(fd, num,
start, size,
signature,
@@ -479,7 +500,8 @@ disk_get_partition_info (int fd,
}
}
error_free_mbr:
- free(mbr_unaligned);
+ free(mbr_sector);
+ error:
return rc;
}
--- a/src/lib/gpt.c
+++ b/src/lib/gpt.c
@@ -218,23 +218,21 @@ read_lba(int fd, uint64_t lba, void *buf
int sector_size = get_sector_size(fd);
off_t offset = lba * sector_size;
ssize_t bytesread;
- void *aligned;
- void *unaligned;
+ void *iobuf;
+ size_t iobuf_size;
+ int rc;
- if (bytes % sector_size)
- return EINVAL;
-
- unaligned = malloc(bytes+sector_size-1);
- aligned = (void *)
- (((unsigned long)unaligned + sector_size - 1) &
- ~(unsigned long)(sector_size-1));
- memset(aligned, 0, bytes);
+ iobuf_size = lcm(bytes, sector_size);
+ rc = posix_memalign(&iobuf, sector_size, iobuf_size);
+ if (rc)
+ return rc;
+ memset(iobuf, 0, bytes);
lseek(fd, offset, SEEK_SET);
- bytesread = read(fd, aligned, bytes);
- memcpy(buffer, aligned, bytesread);
- free(unaligned);
+ bytesread = read(fd, iobuf, iobuf_size);
+ memcpy(buffer, iobuf, bytes);
+ free(iobuf);
/* Kludge. This is necessary to read/write the last
block of an odd-sized disk, until Linux 2.5.x kernel fixes.
