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-rw-r--r--linux/src/drivers/block/ide.c73
1 files changed, 48 insertions, 25 deletions
diff --git a/linux/src/drivers/block/ide.c b/linux/src/drivers/block/ide.c
index cfd8b5b..7ab790d 100644
--- a/linux/src/drivers/block/ide.c
+++ b/linux/src/drivers/block/ide.c
@@ -604,6 +604,9 @@ void ide_set_handler (ide_drive_t *drive, ide_handler_t *handler, unsigned int t
*
* Returns: 1 if lba_capacity looks sensible
* 0 otherwise
+ *
+ * Note: we must not change id->cyls here, otherwise a second call
+ * of this routine might no longer find lba_capacity ok.
*/
static int lba_capacity_is_ok (struct hd_driveid *id)
{
@@ -611,10 +614,16 @@ static int lba_capacity_is_ok (struct hd_driveid *id)
unsigned long chs_sects = id->cyls * id->heads * id->sectors;
unsigned long _10_percent = chs_sects / 10;
- /* very large drives (8GB+) may lie about the number of cylinders */
- if (id->cyls == 16383 && id->heads == 16 && id->sectors == 63 && lba_sects > chs_sects) {
+ /*
+ * The ATA spec tells large drives to return
+ * C/H/S = 16383/16/63 independent of their size.
+ * Some drives can be jumpered to use 15 heads instead of 16.
+ */
+ if (id->cyls == 16383 && id->sectors == 63 &&
+ (id->heads == 15 || id->heads == 16) &&
+ id->lba_capacity >= 16383*63*id->heads)
return 1; /* lba_capacity is our only option */
- }
+
/* perform a rough sanity check on lba_sects: within 10% is "okay" */
if ((lba_sects - chs_sects) < _10_percent)
return 1; /* lba_capacity is good */
@@ -631,11 +640,13 @@ static int lba_capacity_is_ok (struct hd_driveid *id)
/*
* current_capacity() returns the capacity (in sectors) of a drive
* according to its current geometry/LBA settings.
+ *
+ * It also sets select.b.lba.
*/
static unsigned long current_capacity (ide_drive_t *drive)
{
struct hd_driveid *id = drive->id;
- unsigned long capacity = drive->cyl * drive->head * drive->sect;
+ unsigned long capacity;
if (!drive->present)
return 0;
@@ -645,8 +656,10 @@ static unsigned long current_capacity (ide_drive_t *drive)
#endif /* CONFIG_BLK_DEV_IDEFLOPPY */
if (drive->media != ide_disk)
return 0x7fffffff; /* cdrom or tape */
+
drive->select.b.lba = 0;
/* Determine capacity, and use LBA if the drive properly supports it */
+ capacity = drive->cyl * drive->head * drive->sect;
if (id != NULL && (id->capability & 2) && lba_capacity_is_ok(id)) {
if (id->lba_capacity >= capacity) {
capacity = id->lba_capacity;
@@ -2568,8 +2581,7 @@ static inline void do_identify (ide_drive_t *drive, byte cmd)
}
/* Handle logical geometry translation by the drive */
if ((id->field_valid & 1) && id->cur_cyls && id->cur_heads
- && (id->cur_heads <= 16) && id->cur_sectors)
- {
+ && (id->cur_heads <= 16) && id->cur_sectors) {
/*
* Extract the physical drive geometry for our use.
* Note that we purposely do *not* update the bios info.
@@ -2594,7 +2606,8 @@ static inline void do_identify (ide_drive_t *drive, byte cmd)
}
}
/* Use physical geometry if what we have still makes no sense */
- if ((!drive->head || drive->head > 16) && id->heads && id->heads <= 16) {
+ if ((!drive->head || drive->head > 16) &&
+ id->heads && id->heads <= 16) {
drive->cyl = id->cyls;
drive->head = id->heads;
drive->sect = id->sectors;
@@ -2603,21 +2616,22 @@ static inline void do_identify (ide_drive_t *drive, byte cmd)
/* calculate drive capacity, and select LBA if possible */
capacity = current_capacity (drive);
- /* Correct the number of cyls if the bios value is too small */
- if (!drive->forced_geom &&
- capacity > drive->bios_cyl * drive->bios_sect * drive->bios_head) {
- unsigned long cylsize;
- cylsize = drive->bios_sect * drive->bios_head;
- if (cylsize == 0 || capacity/cylsize > 65535) {
- drive->bios_sect = 63;
- drive->bios_head = 255;
- cylsize = 63*255;
- }
- if (capacity/cylsize > 65535)
- drive->bios_cyl = 65535;
- else
- drive->bios_cyl = capacity/cylsize;
- }
+ /*
+ * if possible, give fdisk access to more of the drive,
+ * by correcting bios_cyls:
+ */
+ if (capacity > drive->bios_cyl * drive->bios_head * drive->bios_sect
+ && !drive->forced_geom && drive->bios_sect && drive->bios_head) {
+ int cyl = (capacity / drive->bios_sect) / drive->bios_head;
+ if (cyl <= 65535)
+ drive->bios_cyl = cyl;
+ else {
+ /* OK until 539 GB */
+ drive->bios_sect = 63;
+ drive->bios_head = 255;
+ drive->bios_cyl = capacity / (63*255);
+ }
+ }
if (!strncmp((char *)id->model, "BMI ", 4) &&
strstr((char *)id->model, " ENHANCED IDE ") &&
@@ -3346,7 +3360,7 @@ done:
* This routine is called from the partition-table code in genhd.c
* to "convert" a drive to a logical geometry with fewer than 1024 cyls.
*
- * The second parameter, "xparm", determines exactly how the translation
+ * The second parameter, "xparm", determines exactly how the translation
* will be handled:
* 0 = convert to CHS with fewer than 1024 cyls
* using the same method as Ontrack DiskManager.
@@ -3354,10 +3368,11 @@ done:
* -1 = similar to "0", plus redirect sector 0 to sector 1.
* >1 = convert to a CHS geometry with "xparm" heads.
*
- * Returns 0 if the translation was not possible, if the device was not
+ * Returns 0 if the translation was not possible, if the device was not
* an IDE disk drive, or if a geometry was "forced" on the commandline.
* Returns 1 if the geometry translation was successful.
*/
+
int ide_xlate_1024 (kdev_t i_rdev, int xparm, const char *msg)
{
ide_drive_t *drive;
@@ -3365,7 +3380,11 @@ int ide_xlate_1024 (kdev_t i_rdev, int xparm, const char *msg)
const byte *heads = head_vals;
unsigned long tracks;
- if ((drive = get_info_ptr(i_rdev)) == NULL || drive->forced_geom)
+ drive = get_info_ptr(i_rdev);
+ if (!drive)
+ return 0;
+
+ if (drive->forced_geom)
return 0;
if (xparm > 1 && xparm <= drive->bios_head && drive->bios_sect == 63)
@@ -3373,6 +3392,10 @@ int ide_xlate_1024 (kdev_t i_rdev, int xparm, const char *msg)
printk("%s ", msg);
+ if (xparm < 0 && (drive->bios_cyl * drive->bios_head * drive->bios_sect) < (1024 * 16 * 63)) {
+ return 0; /* small disk: no translation needed */
+ }
+
if (drive->id) {
drive->cyl = drive->id->cyls;
drive->head = drive->id->heads;