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linux/drivers/ide/arm/rapide.c
Bartlomiej Zolnierkiewicz 93de00fd1c ide: remove broken/dangerous HDIO_[UNREGISTER,SCAN]_HWIF ioctls (take 3)
hdparm explicitely marks HDIO_[UNREGISTER,SCAN]_HWIF ioctls as DANGEROUS
and given the number of bugs we can assume that there are no real users:

* DMA has no chance of working because DMA resources are released by
  ide_unregister() and they are never allocated again.

* Since ide_init_hwif_ports() is used for ->io_ports[] setup the ioctls
  don't work for almost all hosts with "non-standard" (== non ISA-like)
  layout of IDE taskfile registers (there is a lot of such host drivers).

* ide_port_init_devices() is not called when probing IDE devices so:
  - drive->autotune is never set and IDE host/devices are not programmed
    for the correct PIO/DMA transfer modes (=> possible data corruption)
  - host specific I/O 32-bit and IRQ unmasking settings are not applied
    (=> possible data corruption)
  - host specific ->port_init_devs method is not called (=> no luck with
    ht6560b, qd65xx and opti621 host drivers)

* ->rw_disk method is not preserved (=> no HPT3xxN chipsets support).

* ->serialized flag is not preserved (=> possible data corruption when
   using icside, aec62xx (ATP850UF chipset), cmd640, cs5530, hpt366
   (HPT3xxN chipsets), rz1000, sc1200, dtc2278 and ht6560b host drivers).

* ->ack_intr method is not preserved (=> needed by ide-cris, buddha,
  gayle and macide host drivers).

* ->sata_scr[] and sata_misc[] is cleared by ide_unregister() and it
  isn't initialized again (SiI3112 support needs them).

* To issue an ioctl() there need to be at least one IDE device present
  in the system.

* ->cable_detect method is not preserved + it is not called when probing
  IDE devices so cable detection is broken (however since DMA support is
  also broken it doesn't really matter ;-).

* Some objects which may have already been freed in ide_unregister()
  are restored by ide_hwif_restore() (i.e. ->hwgroup).

* ide_register_hw() may unregister unrelated IDE ports if free ide_hwifs[]
  slot cannot be found.

* When IDE host drivers are modular unregistered port may be re-used by
  different host driver that owned it first causing subtle bugs.

Since we now have a proper warm-plug support remove these ioctls,
then remove no longer needed:
- ide_register_hw() and ide_hwif_restore() functions
- 'init_default' and 'restore' arguments of ide_unregister()
- zeroeing of hwif->{dma,extra}_* fields in ide_unregister()

As an added bonus IDE core code size shrinks by ~3kB (x86-32).

v2:
* fix ide_unregister() arguments in cleanup_module() (Andrew Morton).

v3:
* fix ide_unregister() arguments in palm_bk3710.c.

Acked-by: Sergei Shtylyov <sshtylyov@ru.mvista.com>
Signed-off-by: Bartlomiej Zolnierkiewicz <bzolnier@gmail.com>
2008-04-18 00:46:24 +02:00

107 lines
2.0 KiB
C

/*
* Copyright (c) 1996-2002 Russell King.
*/
#include <linux/module.h>
#include <linux/slab.h>
#include <linux/blkdev.h>
#include <linux/errno.h>
#include <linux/ide.h>
#include <linux/init.h>
#include <asm/ecard.h>
static void rapide_setup_ports(hw_regs_t *hw, void __iomem *base,
void __iomem *ctrl, unsigned int sz, int irq)
{
unsigned long port = (unsigned long)base;
int i;
for (i = IDE_DATA_OFFSET; i <= IDE_STATUS_OFFSET; i++) {
hw->io_ports[i] = port;
port += sz;
}
hw->io_ports[IDE_CONTROL_OFFSET] = (unsigned long)ctrl;
hw->irq = irq;
}
static int __devinit
rapide_probe(struct expansion_card *ec, const struct ecard_id *id)
{
ide_hwif_t *hwif;
void __iomem *base;
int ret;
u8 idx[4] = { 0xff, 0xff, 0xff, 0xff };
hw_regs_t hw;
ret = ecard_request_resources(ec);
if (ret)
goto out;
base = ecardm_iomap(ec, ECARD_RES_MEMC, 0, 0);
if (!base) {
ret = -ENOMEM;
goto release;
}
hwif = ide_find_port((unsigned long)base);
if (hwif) {
memset(&hw, 0, sizeof(hw));
rapide_setup_ports(&hw, base, base + 0x818, 1 << 6, ec->irq);
hw.chipset = ide_generic;
hw.dev = &ec->dev;
ide_init_port_hw(hwif, &hw);
hwif->mmio = 1;
default_hwif_mmiops(hwif);
idx[0] = hwif->index;
ide_device_add(idx, NULL);
ecard_set_drvdata(ec, hwif);
goto out;
}
release:
ecard_release_resources(ec);
out:
return ret;
}
static void __devexit rapide_remove(struct expansion_card *ec)
{
ide_hwif_t *hwif = ecard_get_drvdata(ec);
ecard_set_drvdata(ec, NULL);
ide_unregister(hwif->index);
ecard_release_resources(ec);
}
static struct ecard_id rapide_ids[] = {
{ MANU_YELLOWSTONE, PROD_YELLOWSTONE_RAPIDE32 },
{ 0xffff, 0xffff }
};
static struct ecard_driver rapide_driver = {
.probe = rapide_probe,
.remove = __devexit_p(rapide_remove),
.id_table = rapide_ids,
.drv = {
.name = "rapide",
},
};
static int __init rapide_init(void)
{
return ecard_register_driver(&rapide_driver);
}
MODULE_LICENSE("GPL");
MODULE_DESCRIPTION("Yellowstone RAPIDE driver");
module_init(rapide_init);