linux/drivers/ide/legacy/hd.c

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/*
* Copyright (C) 1991, 1992 Linus Torvalds
*
* This is the low-level hd interrupt support. It traverses the
* request-list, using interrupts to jump between functions. As
* all the functions are called within interrupts, we may not
* sleep. Special care is recommended.
*
* modified by Drew Eckhardt to check nr of hd's from the CMOS.
*
* Thanks to Branko Lankester, lankeste@fwi.uva.nl, who found a bug
* in the early extended-partition checks and added DM partitions
*
* IRQ-unmask, drive-id, multiple-mode, support for ">16 heads",
* and general streamlining by Mark Lord.
*
* Removed 99% of above. Use Mark's ide driver for those options.
* This is now a lightweight ST-506 driver. (Paul Gortmaker)
*
* Modified 1995 Russell King for ARM processor.
*
* Bugfix: max_sectors must be <= 255 or the wheels tend to come
* off in a hurry once you queue things up - Paul G. 02/2001
*/
/* Uncomment the following if you want verbose error reports. */
/* #define VERBOSE_ERRORS */
#include <linux/blkdev.h>
#include <linux/errno.h>
#include <linux/signal.h>
#include <linux/interrupt.h>
#include <linux/timer.h>
#include <linux/fs.h>
#include <linux/kernel.h>
#include <linux/genhd.h>
#include <linux/slab.h>
#include <linux/string.h>
#include <linux/ioport.h>
#include <linux/mc146818rtc.h> /* CMOS defines */
#include <linux/init.h>
#include <linux/blkpg.h>
#include <linux/hdreg.h>
#define REALLY_SLOW_IO
#include <asm/system.h>
#include <asm/io.h>
#include <asm/uaccess.h>
#ifdef __arm__
#undef HD_IRQ
#endif
#include <asm/irq.h>
#ifdef __arm__
#define HD_IRQ IRQ_HARDDISK
#endif
/* Hd controller regster ports */
#define HD_DATA 0x1f0 /* _CTL when writing */
#define HD_ERROR 0x1f1 /* see err-bits */
#define HD_NSECTOR 0x1f2 /* nr of sectors to read/write */
#define HD_SECTOR 0x1f3 /* starting sector */
#define HD_LCYL 0x1f4 /* starting cylinder */
#define HD_HCYL 0x1f5 /* high byte of starting cyl */
#define HD_CURRENT 0x1f6 /* 101dhhhh , d=drive, hhhh=head */
#define HD_STATUS 0x1f7 /* see status-bits */
#define HD_FEATURE HD_ERROR /* same io address, read=error, write=feature */
#define HD_PRECOMP HD_FEATURE /* obsolete use of this port - predates IDE */
#define HD_COMMAND HD_STATUS /* same io address, read=status, write=cmd */
#define HD_CMD 0x3f6 /* used for resets */
#define HD_ALTSTATUS 0x3f6 /* same as HD_STATUS but doesn't clear irq */
/* Bits of HD_STATUS */
#define ERR_STAT 0x01
#define INDEX_STAT 0x02
#define ECC_STAT 0x04 /* Corrected error */
#define DRQ_STAT 0x08
#define SEEK_STAT 0x10
#define SERVICE_STAT SEEK_STAT
#define WRERR_STAT 0x20
#define READY_STAT 0x40
#define BUSY_STAT 0x80
/* Bits for HD_ERROR */
#define MARK_ERR 0x01 /* Bad address mark */
#define TRK0_ERR 0x02 /* couldn't find track 0 */
#define ABRT_ERR 0x04 /* Command aborted */
#define MCR_ERR 0x08 /* media change request */
#define ID_ERR 0x10 /* ID field not found */
#define MC_ERR 0x20 /* media changed */
#define ECC_ERR 0x40 /* Uncorrectable ECC error */
#define BBD_ERR 0x80 /* pre-EIDE meaning: block marked bad */
#define ICRC_ERR 0x80 /* new meaning: CRC error during transfer */
static DEFINE_SPINLOCK(hd_lock);
static struct request_queue *hd_queue;
#define MAJOR_NR HD_MAJOR
#define QUEUE (hd_queue)
#define CURRENT elv_next_request(hd_queue)
#define TIMEOUT_VALUE (6*HZ)
#define HD_DELAY 0
#define MAX_ERRORS 16 /* Max read/write errors/sector */
#define RESET_FREQ 8 /* Reset controller every 8th retry */
#define RECAL_FREQ 4 /* Recalibrate every 4th retry */
#define MAX_HD 2
#define STAT_OK (READY_STAT|SEEK_STAT)
#define OK_STATUS(s) (((s)&(STAT_OK|(BUSY_STAT|WRERR_STAT|ERR_STAT)))==STAT_OK)
static void recal_intr(void);
static void bad_rw_intr(void);
static int reset;
static int hd_error;
/*
* This struct defines the HD's and their types.
*/
struct hd_i_struct {
unsigned int head,sect,cyl,wpcom,lzone,ctl;
int unit;
int recalibrate;
int special_op;
};
#ifdef HD_TYPE
static struct hd_i_struct hd_info[] = { HD_TYPE };
static int NR_HD = ((sizeof (hd_info))/(sizeof (struct hd_i_struct)));
#else
static struct hd_i_struct hd_info[MAX_HD];
static int NR_HD;
#endif
static struct gendisk *hd_gendisk[MAX_HD];
static struct timer_list device_timer;
#define TIMEOUT_VALUE (6*HZ)
#define SET_TIMER \
do { \
mod_timer(&device_timer, jiffies + TIMEOUT_VALUE); \
} while (0)
static void (*do_hd)(void) = NULL;
#define SET_HANDLER(x) \
if ((do_hd = (x)) != NULL) \
SET_TIMER; \
else \
del_timer(&device_timer);
#if (HD_DELAY > 0)
#include <asm/i8253.h>
unsigned long last_req;
unsigned long read_timer(void)
{
unsigned long t, flags;
int i;
spin_lock_irqsave(&i8253_lock, flags);
t = jiffies * 11932;
outb_p(0, 0x43);
i = inb_p(0x40);
i |= inb(0x40) << 8;
spin_unlock_irqrestore(&i8253_lock, flags);
return(t - i);
}
#endif
static void __init hd_setup(char *str, int *ints)
{
int hdind = 0;
if (ints[0] != 3)
return;
if (hd_info[0].head != 0)
hdind=1;
hd_info[hdind].head = ints[2];
hd_info[hdind].sect = ints[3];
hd_info[hdind].cyl = ints[1];
hd_info[hdind].wpcom = 0;
hd_info[hdind].lzone = ints[1];
hd_info[hdind].ctl = (ints[2] > 8 ? 8 : 0);
NR_HD = hdind+1;
}
static void dump_status (const char *msg, unsigned int stat)
{
char *name = "hd?";
if (CURRENT)
name = CURRENT->rq_disk->disk_name;
#ifdef VERBOSE_ERRORS
printk("%s: %s: status=0x%02x { ", name, msg, stat & 0xff);
if (stat & BUSY_STAT) printk("Busy ");
if (stat & READY_STAT) printk("DriveReady ");
if (stat & WRERR_STAT) printk("WriteFault ");
if (stat & SEEK_STAT) printk("SeekComplete ");
if (stat & DRQ_STAT) printk("DataRequest ");
if (stat & ECC_STAT) printk("CorrectedError ");
if (stat & INDEX_STAT) printk("Index ");
if (stat & ERR_STAT) printk("Error ");
printk("}\n");
if ((stat & ERR_STAT) == 0) {
hd_error = 0;
} else {
hd_error = inb(HD_ERROR);
printk("%s: %s: error=0x%02x { ", name, msg, hd_error & 0xff);
if (hd_error & BBD_ERR) printk("BadSector ");
if (hd_error & ECC_ERR) printk("UncorrectableError ");
if (hd_error & ID_ERR) printk("SectorIdNotFound ");
if (hd_error & ABRT_ERR) printk("DriveStatusError ");
if (hd_error & TRK0_ERR) printk("TrackZeroNotFound ");
if (hd_error & MARK_ERR) printk("AddrMarkNotFound ");
printk("}");
if (hd_error & (BBD_ERR|ECC_ERR|ID_ERR|MARK_ERR)) {
printk(", CHS=%d/%d/%d", (inb(HD_HCYL)<<8) + inb(HD_LCYL),
inb(HD_CURRENT) & 0xf, inb(HD_SECTOR));
if (CURRENT)
printk(", sector=%ld", CURRENT->sector);
}
printk("\n");
}
#else
printk("%s: %s: status=0x%02x.\n", name, msg, stat & 0xff);
if ((stat & ERR_STAT) == 0) {
hd_error = 0;
} else {
hd_error = inb(HD_ERROR);
printk("%s: %s: error=0x%02x.\n", name, msg, hd_error & 0xff);
}
#endif
}
static void check_status(void)
{
int i = inb_p(HD_STATUS);
if (!OK_STATUS(i)) {
dump_status("check_status", i);
bad_rw_intr();
}
}
static int controller_busy(void)
{
int retries = 100000;
unsigned char status;
do {
status = inb_p(HD_STATUS);
} while ((status & BUSY_STAT) && --retries);
return status;
}
static int status_ok(void)
{
unsigned char status = inb_p(HD_STATUS);
if (status & BUSY_STAT)
return 1; /* Ancient, but does it make sense??? */
if (status & WRERR_STAT)
return 0;
if (!(status & READY_STAT))
return 0;
if (!(status & SEEK_STAT))
return 0;
return 1;
}
static int controller_ready(unsigned int drive, unsigned int head)
{
int retry = 100;
do {
if (controller_busy() & BUSY_STAT)
return 0;
outb_p(0xA0 | (drive<<4) | head, HD_CURRENT);
if (status_ok())
return 1;
} while (--retry);
return 0;
}
static void hd_out(struct hd_i_struct *disk,
unsigned int nsect,
unsigned int sect,
unsigned int head,
unsigned int cyl,
unsigned int cmd,
void (*intr_addr)(void))
{
unsigned short port;
#if (HD_DELAY > 0)
while (read_timer() - last_req < HD_DELAY)
/* nothing */;
#endif
if (reset)
return;
if (!controller_ready(disk->unit, head)) {
reset = 1;
return;
}
SET_HANDLER(intr_addr);
outb_p(disk->ctl,HD_CMD);
port=HD_DATA;
outb_p(disk->wpcom>>2,++port);
outb_p(nsect,++port);
outb_p(sect,++port);
outb_p(cyl,++port);
outb_p(cyl>>8,++port);
outb_p(0xA0|(disk->unit<<4)|head,++port);
outb_p(cmd,++port);
}
static void hd_request (void);
static int drive_busy(void)
{
unsigned int i;
unsigned char c;
for (i = 0; i < 500000 ; i++) {
c = inb_p(HD_STATUS);
if ((c & (BUSY_STAT | READY_STAT | SEEK_STAT)) == STAT_OK)
return 0;
}
dump_status("reset timed out", c);
return 1;
}
static void reset_controller(void)
{
int i;
outb_p(4,HD_CMD);
for(i = 0; i < 1000; i++) barrier();
outb_p(hd_info[0].ctl & 0x0f,HD_CMD);
for(i = 0; i < 1000; i++) barrier();
if (drive_busy())
printk("hd: controller still busy\n");
else if ((hd_error = inb(HD_ERROR)) != 1)
printk("hd: controller reset failed: %02x\n",hd_error);
}
static void reset_hd(void)
{
static int i;
repeat:
if (reset) {
reset = 0;
i = -1;
reset_controller();
} else {
check_status();
if (reset)
goto repeat;
}
if (++i < NR_HD) {
struct hd_i_struct *disk = &hd_info[i];
disk->special_op = disk->recalibrate = 1;
hd_out(disk,disk->sect,disk->sect,disk->head-1,
disk->cyl,WIN_SPECIFY,&reset_hd);
if (reset)
goto repeat;
} else
hd_request();
}
/*
* Ok, don't know what to do with the unexpected interrupts: on some machines
* doing a reset and a retry seems to result in an eternal loop. Right now I
* ignore it, and just set the timeout.
*
* On laptops (and "green" PCs), an unexpected interrupt occurs whenever the
* drive enters "idle", "standby", or "sleep" mode, so if the status looks
* "good", we just ignore the interrupt completely.
*/
static void unexpected_hd_interrupt(void)
{
unsigned int stat = inb_p(HD_STATUS);
if (stat & (BUSY_STAT|DRQ_STAT|ECC_STAT|ERR_STAT)) {
dump_status ("unexpected interrupt", stat);
SET_TIMER;
}
}
/*
* bad_rw_intr() now tries to be a bit smarter and does things
* according to the error returned by the controller.
* -Mika Liljeberg (liljeber@cs.Helsinki.FI)
*/
static void bad_rw_intr(void)
{
struct request *req = CURRENT;
if (req != NULL) {
struct hd_i_struct *disk = req->rq_disk->private_data;
if (++req->errors >= MAX_ERRORS || (hd_error & BBD_ERR)) {
end_request(req, 0);
disk->special_op = disk->recalibrate = 1;
} else if (req->errors % RESET_FREQ == 0)
reset = 1;
else if ((hd_error & TRK0_ERR) || req->errors % RECAL_FREQ == 0)
disk->special_op = disk->recalibrate = 1;
/* Otherwise just retry */
}
}
static inline int wait_DRQ(void)
{
int retries = 100000, stat;
while (--retries > 0)
if ((stat = inb_p(HD_STATUS)) & DRQ_STAT)
return 0;
dump_status("wait_DRQ", stat);
return -1;
}
static void read_intr(void)
{
struct request *req;
int i, retries = 100000;
do {
i = (unsigned) inb_p(HD_STATUS);
if (i & BUSY_STAT)
continue;
if (!OK_STATUS(i))
break;
if (i & DRQ_STAT)
goto ok_to_read;
} while (--retries > 0);
dump_status("read_intr", i);
bad_rw_intr();
hd_request();
return;
ok_to_read:
req = CURRENT;
insw(HD_DATA,req->buffer,256);
req->sector++;
req->buffer += 512;
req->errors = 0;
i = --req->nr_sectors;
--req->current_nr_sectors;
#ifdef DEBUG
printk("%s: read: sector %ld, remaining = %ld, buffer=%p\n",
req->rq_disk->disk_name, req->sector, req->nr_sectors,
req->buffer+512));
#endif
if (req->current_nr_sectors <= 0)
end_request(req, 1);
if (i > 0) {
SET_HANDLER(&read_intr);
return;
}
(void) inb_p(HD_STATUS);
#if (HD_DELAY > 0)
last_req = read_timer();
#endif
if (elv_next_request(QUEUE))
hd_request();
return;
}
static void write_intr(void)
{
struct request *req = CURRENT;
int i;
int retries = 100000;
do {
i = (unsigned) inb_p(HD_STATUS);
if (i & BUSY_STAT)
continue;
if (!OK_STATUS(i))
break;
if ((req->nr_sectors <= 1) || (i & DRQ_STAT))
goto ok_to_write;
} while (--retries > 0);
dump_status("write_intr", i);
bad_rw_intr();
hd_request();
return;
ok_to_write:
req->sector++;
i = --req->nr_sectors;
--req->current_nr_sectors;
req->buffer += 512;
if (!i || (req->bio && req->current_nr_sectors <= 0))
end_request(req, 1);
if (i > 0) {
SET_HANDLER(&write_intr);
outsw(HD_DATA,req->buffer,256);
local_irq_enable();
} else {
#if (HD_DELAY > 0)
last_req = read_timer();
#endif
hd_request();
}
return;
}
static void recal_intr(void)
{
check_status();
#if (HD_DELAY > 0)
last_req = read_timer();
#endif
hd_request();
}
/*
* This is another of the error-routines I don't know what to do with. The
* best idea seems to just set reset, and start all over again.
*/
static void hd_times_out(unsigned long dummy)
{
char *name;
do_hd = NULL;
if (!CURRENT)
return;
disable_irq(HD_IRQ);
local_irq_enable();
reset = 1;
name = CURRENT->rq_disk->disk_name;
printk("%s: timeout\n", name);
if (++CURRENT->errors >= MAX_ERRORS) {
#ifdef DEBUG
printk("%s: too many errors\n", name);
#endif
end_request(CURRENT, 0);
}
local_irq_disable();
hd_request();
enable_irq(HD_IRQ);
}
static int do_special_op(struct hd_i_struct *disk, struct request *req)
{
if (disk->recalibrate) {
disk->recalibrate = 0;
hd_out(disk,disk->sect,0,0,0,WIN_RESTORE,&recal_intr);
return reset;
}
if (disk->head > 16) {
printk ("%s: cannot handle device with more than 16 heads - giving up\n", req->rq_disk->disk_name);
end_request(req, 0);
}
disk->special_op = 0;
return 1;
}
/*
* The driver enables interrupts as much as possible. In order to do this,
* (a) the device-interrupt is disabled before entering hd_request(),
* and (b) the timeout-interrupt is disabled before the sti().
*
* Interrupts are still masked (by default) whenever we are exchanging
* data/cmds with a drive, because some drives seem to have very poor
* tolerance for latency during I/O. The IDE driver has support to unmask
* interrupts for non-broken hardware, so use that driver if required.
*/
static void hd_request(void)
{
unsigned int block, nsect, sec, track, head, cyl;
struct hd_i_struct *disk;
struct request *req;
if (do_hd)
return;
repeat:
del_timer(&device_timer);
local_irq_enable();
req = CURRENT;
if (!req) {
do_hd = NULL;
return;
}
if (reset) {
local_irq_disable();
reset_hd();
return;
}
disk = req->rq_disk->private_data;
block = req->sector;
nsect = req->nr_sectors;
if (block >= get_capacity(req->rq_disk) ||
((block+nsect) > get_capacity(req->rq_disk))) {
printk("%s: bad access: block=%d, count=%d\n",
req->rq_disk->disk_name, block, nsect);
end_request(req, 0);
goto repeat;
}
if (disk->special_op) {
if (do_special_op(disk, req))
goto repeat;
return;
}
sec = block % disk->sect + 1;
track = block / disk->sect;
head = track % disk->head;
cyl = track / disk->head;
#ifdef DEBUG
printk("%s: %sing: CHS=%d/%d/%d, sectors=%d, buffer=%p\n",
req->rq_disk->disk_name, (req->cmd == READ)?"read":"writ",
cyl, head, sec, nsect, req->buffer);
#endif
if (blk_fs_request(req)) {
switch (rq_data_dir(req)) {
case READ:
hd_out(disk,nsect,sec,head,cyl,WIN_READ,&read_intr);
if (reset)
goto repeat;
break;
case WRITE:
hd_out(disk,nsect,sec,head,cyl,WIN_WRITE,&write_intr);
if (reset)
goto repeat;
if (wait_DRQ()) {
bad_rw_intr();
goto repeat;
}
outsw(HD_DATA,req->buffer,256);
break;
default:
printk("unknown hd-command\n");
end_request(req, 0);
break;
}
}
}
static void do_hd_request (request_queue_t * q)
{
disable_irq(HD_IRQ);
hd_request();
enable_irq(HD_IRQ);
}
static int hd_getgeo(struct block_device *bdev, struct hd_geometry *geo)
{
struct hd_i_struct *disk = bdev->bd_disk->private_data;
geo->heads = disk->head;
geo->sectors = disk->sect;
geo->cylinders = disk->cyl;
return 0;
}
/*
* Releasing a block device means we sync() it, so that it can safely
* be forgotten about...
*/
IRQ: Maintain regs pointer globally rather than passing to IRQ handlers Maintain a per-CPU global "struct pt_regs *" variable which can be used instead of passing regs around manually through all ~1800 interrupt handlers in the Linux kernel. The regs pointer is used in few places, but it potentially costs both stack space and code to pass it around. On the FRV arch, removing the regs parameter from all the genirq function results in a 20% speed up of the IRQ exit path (ie: from leaving timer_interrupt() to leaving do_IRQ()). Where appropriate, an arch may override the generic storage facility and do something different with the variable. On FRV, for instance, the address is maintained in GR28 at all times inside the kernel as part of general exception handling. Having looked over the code, it appears that the parameter may be handed down through up to twenty or so layers of functions. Consider a USB character device attached to a USB hub, attached to a USB controller that posts its interrupts through a cascaded auxiliary interrupt controller. A character device driver may want to pass regs to the sysrq handler through the input layer which adds another few layers of parameter passing. I've build this code with allyesconfig for x86_64 and i386. I've runtested the main part of the code on FRV and i386, though I can't test most of the drivers. I've also done partial conversion for powerpc and MIPS - these at least compile with minimal configurations. This will affect all archs. Mostly the changes should be relatively easy. Take do_IRQ(), store the regs pointer at the beginning, saving the old one: struct pt_regs *old_regs = set_irq_regs(regs); And put the old one back at the end: set_irq_regs(old_regs); Don't pass regs through to generic_handle_irq() or __do_IRQ(). In timer_interrupt(), this sort of change will be necessary: - update_process_times(user_mode(regs)); - profile_tick(CPU_PROFILING, regs); + update_process_times(user_mode(get_irq_regs())); + profile_tick(CPU_PROFILING); I'd like to move update_process_times()'s use of get_irq_regs() into itself, except that i386, alone of the archs, uses something other than user_mode(). Some notes on the interrupt handling in the drivers: (*) input_dev() is now gone entirely. The regs pointer is no longer stored in the input_dev struct. (*) finish_unlinks() in drivers/usb/host/ohci-q.c needs checking. It does something different depending on whether it's been supplied with a regs pointer or not. (*) Various IRQ handler function pointers have been moved to type irq_handler_t. Signed-Off-By: David Howells <dhowells@redhat.com> (cherry picked from 1b16e7ac850969f38b375e511e3fa2f474a33867 commit)
2006-10-05 13:55:46 +00:00
static irqreturn_t hd_interrupt(int irq, void *dev_id)
{
void (*handler)(void) = do_hd;
do_hd = NULL;
del_timer(&device_timer);
if (!handler)
handler = unexpected_hd_interrupt;
handler();
local_irq_enable();
return IRQ_HANDLED;
}
static struct block_device_operations hd_fops = {
.getgeo = hd_getgeo,
};
/*
* This is the hard disk IRQ description. The IRQF_DISABLED in sa_flags
* means we run the IRQ-handler with interrupts disabled: this is bad for
* interrupt latency, but anything else has led to problems on some
* machines.
*
* We enable interrupts in some of the routines after making sure it's
* safe.
*/
static int __init hd_init(void)
{
int drive;
if (register_blkdev(MAJOR_NR,"hd"))
return -1;
hd_queue = blk_init_queue(do_hd_request, &hd_lock);
if (!hd_queue) {
unregister_blkdev(MAJOR_NR,"hd");
return -ENOMEM;
}
blk_queue_max_sectors(hd_queue, 255);
init_timer(&device_timer);
device_timer.function = hd_times_out;
blk_queue_hardsect_size(hd_queue, 512);
#ifdef __i386__
if (!NR_HD) {
extern struct drive_info drive_info;
unsigned char *BIOS = (unsigned char *) &drive_info;
unsigned long flags;
int cmos_disks;
for (drive=0 ; drive<2 ; drive++) {
hd_info[drive].cyl = *(unsigned short *) BIOS;
hd_info[drive].head = *(2+BIOS);
hd_info[drive].wpcom = *(unsigned short *) (5+BIOS);
hd_info[drive].ctl = *(8+BIOS);
hd_info[drive].lzone = *(unsigned short *) (12+BIOS);
hd_info[drive].sect = *(14+BIOS);
#ifdef does_not_work_for_everybody_with_scsi_but_helps_ibm_vp
if (hd_info[drive].cyl && NR_HD == drive)
NR_HD++;
#endif
BIOS += 16;
}
/*
We query CMOS about hard disks : it could be that
we have a SCSI/ESDI/etc controller that is BIOS
compatible with ST-506, and thus showing up in our
BIOS table, but not register compatible, and therefore
not present in CMOS.
Furthermore, we will assume that our ST-506 drives
<if any> are the primary drives in the system, and
the ones reflected as drive 1 or 2.
The first drive is stored in the high nibble of CMOS
byte 0x12, the second in the low nibble. This will be
either a 4 bit drive type or 0xf indicating use byte 0x19
for an 8 bit type, drive 1, 0x1a for drive 2 in CMOS.
Needless to say, a non-zero value means we have
an AT controller hard disk for that drive.
Currently the rtc_lock is a bit academic since this
driver is non-modular, but someday... ? Paul G.
*/
spin_lock_irqsave(&rtc_lock, flags);
cmos_disks = CMOS_READ(0x12);
spin_unlock_irqrestore(&rtc_lock, flags);
if (cmos_disks & 0xf0) {
if (cmos_disks & 0x0f)
NR_HD = 2;
else
NR_HD = 1;
}
}
#endif /* __i386__ */
#ifdef __arm__
if (!NR_HD) {
/* We don't know anything about the drive. This means
* that you *MUST* specify the drive parameters to the
* kernel yourself.
*/
printk("hd: no drives specified - use hd=cyl,head,sectors"
" on kernel command line\n");
}
#endif
if (!NR_HD)
goto out;
for (drive=0 ; drive < NR_HD ; drive++) {
struct gendisk *disk = alloc_disk(64);
struct hd_i_struct *p = &hd_info[drive];
if (!disk)
goto Enomem;
disk->major = MAJOR_NR;
disk->first_minor = drive << 6;
disk->fops = &hd_fops;
sprintf(disk->disk_name, "hd%c", 'a'+drive);
disk->private_data = p;
set_capacity(disk, p->head * p->sect * p->cyl);
disk->queue = hd_queue;
p->unit = drive;
hd_gendisk[drive] = disk;
printk ("%s: %luMB, CHS=%d/%d/%d\n",
disk->disk_name, (unsigned long)get_capacity(disk)/2048,
p->cyl, p->head, p->sect);
}
if (request_irq(HD_IRQ, hd_interrupt, IRQF_DISABLED, "hd", NULL)) {
printk("hd: unable to get IRQ%d for the hard disk driver\n",
HD_IRQ);
goto out1;
}
if (!request_region(HD_DATA, 8, "hd")) {
printk(KERN_WARNING "hd: port 0x%x busy\n", HD_DATA);
goto out2;
}
if (!request_region(HD_CMD, 1, "hd(cmd)")) {
printk(KERN_WARNING "hd: port 0x%x busy\n", HD_CMD);
goto out3;
}
/* Let them fly */
for(drive=0; drive < NR_HD; drive++)
add_disk(hd_gendisk[drive]);
return 0;
out3:
release_region(HD_DATA, 8);
out2:
free_irq(HD_IRQ, NULL);
out1:
for (drive = 0; drive < NR_HD; drive++)
put_disk(hd_gendisk[drive]);
NR_HD = 0;
out:
del_timer(&device_timer);
unregister_blkdev(MAJOR_NR,"hd");
blk_cleanup_queue(hd_queue);
return -1;
Enomem:
while (drive--)
put_disk(hd_gendisk[drive]);
goto out;
}
static int __init parse_hd_setup (char *line) {
int ints[6];
(void) get_options(line, ARRAY_SIZE(ints), ints);
hd_setup(NULL, ints);
return 1;
}
__setup("hd=", parse_hd_setup);
module_init(hd_init);