diff options
Diffstat (limited to 'drivers/scsi/scsicam.c')
| -rw-r--r-- | drivers/scsi/scsicam.c | 40 |
1 files changed, 27 insertions, 13 deletions
diff --git a/drivers/scsi/scsicam.c b/drivers/scsi/scsicam.c index b78354fc4b1..92d24d6dcb3 100644 --- a/drivers/scsi/scsicam.c +++ b/drivers/scsi/scsicam.c @@ -11,11 +11,11 @@ */ #include <linux/module.h> +#include <linux/slab.h> #include <linux/fs.h> #include <linux/genhd.h> #include <linux/kernel.h> #include <linux/blkdev.h> -#include <linux/buffer_head.h> #include <asm/unaligned.h> #include <scsi/scsicam.h> @@ -24,6 +24,14 @@ 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); @@ -43,20 +51,23 @@ unsigned char *scsi_bios_ptable(struct block_device *dev) } 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); @@ -68,7 +79,7 @@ int scsicam_bios_param(struct block_device *bdev, sector_t capacity, int *ip) (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 */ @@ -97,15 +108,18 @@ int scsicam_bios_param(struct block_device *bdev, sector_t capacity, int *ip) } 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, @@ -193,7 +207,7 @@ EXPORT_SYMBOL(scsi_partsize); * * WORKING X3T9.2 * DRAFT 792D - * + * see http://www.t10.org/ftp/t10/drafts/cam/cam-r12b.pdf * * Revision 6 * 10-MAR-94 |