static int setsize(unsigned long capacity, unsigned int *cyls, unsigned int *hds,
unsigned int *secs);
+/**
+ * scsi_bios_ptable - Read PC partition table out of first sector of device.
+ * @dev: from this device
+ *
+ * Description: Reads the first sector from the device and returns %0x42 bytes
+ * starting at offset %0x1be.
+ * Returns: partition table in kmalloc(GFP_KERNEL) memory, or NULL on error.
+ */
unsigned char *scsi_bios_ptable(struct block_device *dev)
{
unsigned char *res = kmalloc(66, GFP_KERNEL);
}
EXPORT_SYMBOL(scsi_bios_ptable);
-/*
- * Function : int scsicam_bios_param (struct block_device *bdev, ector_t capacity, int *ip)
+/**
+ * scsicam_bios_param - Determine geometry of a disk in cylinders/heads/sectors.
+ * @bdev: which device
+ * @capacity: size of the disk in sectors
+ * @ip: return value: ip[0]=heads, ip[1]=sectors, ip[2]=cylinders
*
- * Purpose : to determine the BIOS mapping used for a drive in a
+ * Description : determine the BIOS mapping/geometry used for a drive in a
* SCSI-CAM system, storing the results in ip as required
* by the HDIO_GETGEO ioctl().
*
* Returns : -1 on failure, 0 on success.
- *
*/
int scsicam_bios_param(struct block_device *bdev, sector_t capacity, int *ip)
{
unsigned char *p;
+ u64 capacity64 = capacity; /* Suppress gcc warning */
int ret;
p = scsi_bios_ptable(bdev);
(unsigned int *)ip + 0, (unsigned int *)ip + 1);
kfree(p);
- if (ret == -1) {
+ if (ret == -1 && capacity64 < (1ULL << 32)) {
/* pick some standard mapping with at most 1024 cylinders,
and at most 62 sectors per track - this works up to
7905 MB */
}
EXPORT_SYMBOL(scsicam_bios_param);
-/*
- * Function : static int scsi_partsize(unsigned char *buf, unsigned long
- * capacity,unsigned int *cyls, unsigned int *hds, unsigned int *secs);
+/**
+ * scsi_partsize - Parse cylinders/heads/sectors from PC partition table
+ * @buf: partition table, see scsi_bios_ptable()
+ * @capacity: size of the disk in sectors
+ * @cyls: put cylinders here
+ * @hds: put heads here
+ * @secs: put sectors here
*
- * Purpose : to determine the BIOS mapping used to create the partition
+ * Description: determine the BIOS mapping/geometry used to create the partition
* table, storing the results in *cyls, *hds, and *secs
*
- * Returns : -1 on failure, 0 on success.
- *
+ * Returns: -1 on failure, 0 on success.
*/
int scsi_partsize(unsigned char *buf, unsigned long capacity,
*
* WORKING X3T9.2
* DRAFT 792D
- *
+ * see http://www.t10.org/ftp/t10/drafts/cam/cam-r12b.pdf
*
* Revision 6
* 10-MAR-94