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ide: lba_capacity_is_ok() -> ata_id_is_lba_capacity_ok()

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Rename lba_capacity_is_ok() to ata_id_is_lba_capacity_ok()
and move it to <linux/ata.h> (remove needless parens while at it).

Cc: Jeff Garzik <jgarzik@pobox.com>
Signed-off-by: Bartlomiej Zolnierkiewicz <bzolnier@gmail.com>
This commit is contained in:
Bartlomiej Zolnierkiewicz 2008-10-10 22:39:31 +02:00
parent 93734a2344
commit a02227c977
2 changed files with 51 additions and 51 deletions
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50
include/linux/ata.h
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@ -782,6 +782,56 @@ static inline int atapi_id_dmadir(const u16 *dev_id)
return ata_id_major_version(dev_id) >= 7 && (dev_id[62] & 0x8000);
}
/*
* ata_id_is_lba_capacity_ok() performs a sanity check on
* the claimed LBA capacity value for the device.
*
* Returns 1 if LBA capacity looks sensible, 0 otherwise.
*
* It is called only once for each device.
*/
static inline int ata_id_is_lba_capacity_ok(u16 *id)
{
unsigned long lba_sects, chs_sects, head, tail;
/* No non-LBA info .. so valid! */
if (id[ATA_ID_CYLS] == 0)
return 1;
lba_sects = ata_id_u32(id, ATA_ID_LBA_CAPACITY);
/*
* 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.
* Some drives can be jumpered to use 4092 cyls instead of 16383.
*/
if ((id[ATA_ID_CYLS] == 16383 ||
(id[ATA_ID_CYLS] == 4092 && id[ATA_ID_CUR_CYLS] == 16383)) &&
id[ATA_ID_SECTORS] == 63 &&
(id[ATA_ID_HEADS] == 15 || id[ATA_ID_HEADS] == 16) &&
(lba_sects >= 16383 * 63 * id[ATA_ID_HEADS]))
return 1;
chs_sects = id[ATA_ID_CYLS] * id[ATA_ID_HEADS] * id[ATA_ID_SECTORS];
/* perform a rough sanity check on lba_sects: within 10% is OK */
if (lba_sects - chs_sects < chs_sects/10)
return 1;
/* some drives have the word order reversed */
head = (lba_sects >> 16) & 0xffff;
tail = lba_sects & 0xffff;
lba_sects = head | (tail << 16);
if (lba_sects - chs_sects < chs_sects/10) {
*(__le32 *)&id[ATA_ID_LBA_CAPACITY] = __cpu_to_le32(lba_sects);
return 1; /* LBA capacity is (now) good */
}
return 0; /* LBA capacity value may be bad */
}
static inline void ata_id_to_hd_driveid(u16 *id)
{
#ifdef __BIG_ENDIAN