kernel-ark/drivers/ide/ide.c
Dan Carpenter 0860bf9471 ide: silence some underflow warnings
Back in the day we used to just say this code was root only so it was
ok that the bounds checking was sloppy.  These days it annoys static
checkers so we fix it.

In the original code "c > INT_MAX" was never true since "c" was an int.
I am not sure what was intended so I left it alone.  But because I made
"c" unsigned it means we don't have a warning any more.

The second warning is that we cap "i" but allow negatives leading to an
underflow of the ide_disks_chs[] array.  The third set of warnings is
because these values come from the user and we cap most of the upper
bounds but allow negative values.  Negative cylinders doesn't make
sense.

drivers/ide/ide.c:262 ide_set_disk_chs() warn: impossible condition '(c > ((~0 >> 1))) => (s32min-s32max > s32max)'
drivers/ide/ide.c:270 ide_set_disk_chs() warn: check 'ide_disks_chs[i]' for negative offsets 'i' = s32min.  extra = 's32min-19'
drivers/ide/ide.c:271 ide_set_disk_chs() warn: no lower bound on 'h'

Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2016-01-18 14:12:33 -05:00

415 lines
10 KiB
C

/*
* Copyright (C) 1994-1998 Linus Torvalds & authors (see below)
* Copyright (C) 2003-2005, 2007 Bartlomiej Zolnierkiewicz
*/
/*
* Mostly written by Mark Lord <mlord@pobox.com>
* and Gadi Oxman <gadio@netvision.net.il>
* and Andre Hedrick <andre@linux-ide.org>
*
* See linux/MAINTAINERS for address of current maintainer.
*
* This is the multiple IDE interface driver, as evolved from hd.c.
* It supports up to MAX_HWIFS IDE interfaces, on one or more IRQs
* (usually 14 & 15).
* There can be up to two drives per interface, as per the ATA-2 spec.
*
* ...
*
* From hd.c:
* |
* | It traverses the request-list, using interrupts to jump between functions.
* | As nearly all functions can be called within interrupts, we may not sleep.
* | Special care is recommended. Have Fun!
* |
* | 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.
* |
* | Early work on error handling by Mika Liljeberg (liljeber@cs.Helsinki.FI).
* |
* | IRQ-unmask, drive-id, multiple-mode, support for ">16 heads",
* | and general streamlining by Mark Lord (mlord@pobox.com).
*
* October, 1994 -- Complete line-by-line overhaul for linux 1.1.x, by:
*
* Mark Lord (mlord@pobox.com) (IDE Perf.Pkg)
* Delman Lee (delman@ieee.org) ("Mr. atdisk2")
* Scott Snyder (snyder@fnald0.fnal.gov) (ATAPI IDE cd-rom)
*
* This was a rewrite of just about everything from hd.c, though some original
* code is still sprinkled about. Think of it as a major evolution, with
* inspiration from lots of linux users, esp. hamish@zot.apana.org.au
*/
#include <linux/module.h>
#include <linux/types.h>
#include <linux/string.h>
#include <linux/kernel.h>
#include <linux/interrupt.h>
#include <linux/major.h>
#include <linux/errno.h>
#include <linux/genhd.h>
#include <linux/init.h>
#include <linux/pci.h>
#include <linux/ide.h>
#include <linux/hdreg.h>
#include <linux/completion.h>
#include <linux/device.h>
struct class *ide_port_class;
/**
* ide_device_get - get an additional reference to a ide_drive_t
* @drive: device to get a reference to
*
* Gets a reference to the ide_drive_t and increments the use count of the
* underlying LLDD module.
*/
int ide_device_get(ide_drive_t *drive)
{
struct device *host_dev;
struct module *module;
if (!get_device(&drive->gendev))
return -ENXIO;
host_dev = drive->hwif->host->dev[0];
module = host_dev ? host_dev->driver->owner : NULL;
if (module && !try_module_get(module)) {
put_device(&drive->gendev);
return -ENXIO;
}
return 0;
}
EXPORT_SYMBOL_GPL(ide_device_get);
/**
* ide_device_put - release a reference to a ide_drive_t
* @drive: device to release a reference on
*
* Release a reference to the ide_drive_t and decrements the use count of
* the underlying LLDD module.
*/
void ide_device_put(ide_drive_t *drive)
{
#ifdef CONFIG_MODULE_UNLOAD
struct device *host_dev = drive->hwif->host->dev[0];
struct module *module = host_dev ? host_dev->driver->owner : NULL;
module_put(module);
#endif
put_device(&drive->gendev);
}
EXPORT_SYMBOL_GPL(ide_device_put);
static int ide_bus_match(struct device *dev, struct device_driver *drv)
{
return 1;
}
static int ide_uevent(struct device *dev, struct kobj_uevent_env *env)
{
ide_drive_t *drive = to_ide_device(dev);
add_uevent_var(env, "MEDIA=%s", ide_media_string(drive));
add_uevent_var(env, "DRIVENAME=%s", drive->name);
add_uevent_var(env, "MODALIAS=ide:m-%s", ide_media_string(drive));
return 0;
}
static int generic_ide_probe(struct device *dev)
{
ide_drive_t *drive = to_ide_device(dev);
struct ide_driver *drv = to_ide_driver(dev->driver);
return drv->probe ? drv->probe(drive) : -ENODEV;
}
static int generic_ide_remove(struct device *dev)
{
ide_drive_t *drive = to_ide_device(dev);
struct ide_driver *drv = to_ide_driver(dev->driver);
if (drv->remove)
drv->remove(drive);
return 0;
}
static void generic_ide_shutdown(struct device *dev)
{
ide_drive_t *drive = to_ide_device(dev);
struct ide_driver *drv = to_ide_driver(dev->driver);
if (dev->driver && drv->shutdown)
drv->shutdown(drive);
}
struct bus_type ide_bus_type = {
.name = "ide",
.match = ide_bus_match,
.uevent = ide_uevent,
.probe = generic_ide_probe,
.remove = generic_ide_remove,
.shutdown = generic_ide_shutdown,
.dev_groups = ide_dev_groups,
.suspend = generic_ide_suspend,
.resume = generic_ide_resume,
};
EXPORT_SYMBOL_GPL(ide_bus_type);
int ide_vlb_clk;
EXPORT_SYMBOL_GPL(ide_vlb_clk);
module_param_named(vlb_clock, ide_vlb_clk, int, 0);
MODULE_PARM_DESC(vlb_clock, "VLB clock frequency (in MHz)");
int ide_pci_clk;
EXPORT_SYMBOL_GPL(ide_pci_clk);
module_param_named(pci_clock, ide_pci_clk, int, 0);
MODULE_PARM_DESC(pci_clock, "PCI bus clock frequency (in MHz)");
static int ide_set_dev_param_mask(const char *s, const struct kernel_param *kp)
{
unsigned int a, b, i, j = 1;
unsigned int *dev_param_mask = (unsigned int *)kp->arg;
/* controller . device (0 or 1) [ : 1 (set) | 0 (clear) ] */
if (sscanf(s, "%u.%u:%u", &a, &b, &j) != 3 &&
sscanf(s, "%u.%u", &a, &b) != 2)
return -EINVAL;
i = a * MAX_DRIVES + b;
if (i >= MAX_HWIFS * MAX_DRIVES || j > 1)
return -EINVAL;
if (j)
*dev_param_mask |= (1 << i);
else
*dev_param_mask &= ~(1 << i);
return 0;
}
static const struct kernel_param_ops param_ops_ide_dev_mask = {
.set = ide_set_dev_param_mask
};
#define param_check_ide_dev_mask(name, p) param_check_uint(name, p)
static unsigned int ide_nodma;
module_param_named(nodma, ide_nodma, ide_dev_mask, 0);
MODULE_PARM_DESC(nodma, "disallow DMA for a device");
static unsigned int ide_noflush;
module_param_named(noflush, ide_noflush, ide_dev_mask, 0);
MODULE_PARM_DESC(noflush, "disable flush requests for a device");
static unsigned int ide_nohpa;
module_param_named(nohpa, ide_nohpa, ide_dev_mask, 0);
MODULE_PARM_DESC(nohpa, "disable Host Protected Area for a device");
static unsigned int ide_noprobe;
module_param_named(noprobe, ide_noprobe, ide_dev_mask, 0);
MODULE_PARM_DESC(noprobe, "skip probing for a device");
static unsigned int ide_nowerr;
module_param_named(nowerr, ide_nowerr, ide_dev_mask, 0);
MODULE_PARM_DESC(nowerr, "ignore the ATA_DF bit for a device");
static unsigned int ide_cdroms;
module_param_named(cdrom, ide_cdroms, ide_dev_mask, 0);
MODULE_PARM_DESC(cdrom, "force device as a CD-ROM");
struct chs_geom {
unsigned int cyl;
u8 head;
u8 sect;
};
static unsigned int ide_disks;
static struct chs_geom ide_disks_chs[MAX_HWIFS * MAX_DRIVES];
static int ide_set_disk_chs(const char *str, struct kernel_param *kp)
{
unsigned int a, b, c = 0, h = 0, s = 0, i, j = 1;
/* controller . device (0 or 1) : Cylinders , Heads , Sectors */
/* controller . device (0 or 1) : 1 (use CHS) | 0 (ignore CHS) */
if (sscanf(str, "%u.%u:%u,%u,%u", &a, &b, &c, &h, &s) != 5 &&
sscanf(str, "%u.%u:%u", &a, &b, &j) != 3)
return -EINVAL;
i = a * MAX_DRIVES + b;
if (i >= MAX_HWIFS * MAX_DRIVES || j > 1)
return -EINVAL;
if (c > INT_MAX || h > 255 || s > 255)
return -EINVAL;
if (j)
ide_disks |= (1 << i);
else
ide_disks &= ~(1 << i);
ide_disks_chs[i].cyl = c;
ide_disks_chs[i].head = h;
ide_disks_chs[i].sect = s;
return 0;
}
module_param_call(chs, ide_set_disk_chs, NULL, NULL, 0);
MODULE_PARM_DESC(chs, "force device as a disk (using CHS)");
static void ide_dev_apply_params(ide_drive_t *drive, u8 unit)
{
int i = drive->hwif->index * MAX_DRIVES + unit;
if (ide_nodma & (1 << i)) {
printk(KERN_INFO "ide: disallowing DMA for %s\n", drive->name);
drive->dev_flags |= IDE_DFLAG_NODMA;
}
if (ide_noflush & (1 << i)) {
printk(KERN_INFO "ide: disabling flush requests for %s\n",
drive->name);
drive->dev_flags |= IDE_DFLAG_NOFLUSH;
}
if (ide_nohpa & (1 << i)) {
printk(KERN_INFO "ide: disabling Host Protected Area for %s\n",
drive->name);
drive->dev_flags |= IDE_DFLAG_NOHPA;
}
if (ide_noprobe & (1 << i)) {
printk(KERN_INFO "ide: skipping probe for %s\n", drive->name);
drive->dev_flags |= IDE_DFLAG_NOPROBE;
}
if (ide_nowerr & (1 << i)) {
printk(KERN_INFO "ide: ignoring the ATA_DF bit for %s\n",
drive->name);
drive->bad_wstat = BAD_R_STAT;
}
if (ide_cdroms & (1 << i)) {
printk(KERN_INFO "ide: forcing %s as a CD-ROM\n", drive->name);
drive->dev_flags |= IDE_DFLAG_PRESENT;
drive->media = ide_cdrom;
/* an ATAPI device ignores DRDY */
drive->ready_stat = 0;
}
if (ide_disks & (1 << i)) {
drive->cyl = drive->bios_cyl = ide_disks_chs[i].cyl;
drive->head = drive->bios_head = ide_disks_chs[i].head;
drive->sect = drive->bios_sect = ide_disks_chs[i].sect;
printk(KERN_INFO "ide: forcing %s as a disk (%d/%d/%d)\n",
drive->name,
drive->cyl, drive->head, drive->sect);
drive->dev_flags |= IDE_DFLAG_FORCED_GEOM | IDE_DFLAG_PRESENT;
drive->media = ide_disk;
drive->ready_stat = ATA_DRDY;
}
}
static unsigned int ide_ignore_cable;
static int ide_set_ignore_cable(const char *s, struct kernel_param *kp)
{
int i, j = 1;
/* controller (ignore) */
/* controller : 1 (ignore) | 0 (use) */
if (sscanf(s, "%d:%d", &i, &j) != 2 && sscanf(s, "%d", &i) != 1)
return -EINVAL;
if (i >= MAX_HWIFS || j < 0 || j > 1)
return -EINVAL;
if (j)
ide_ignore_cable |= (1 << i);
else
ide_ignore_cable &= ~(1 << i);
return 0;
}
module_param_call(ignore_cable, ide_set_ignore_cable, NULL, NULL, 0);
MODULE_PARM_DESC(ignore_cable, "ignore cable detection");
void ide_port_apply_params(ide_hwif_t *hwif)
{
ide_drive_t *drive;
int i;
if (ide_ignore_cable & (1 << hwif->index)) {
printk(KERN_INFO "ide: ignoring cable detection for %s\n",
hwif->name);
hwif->cbl = ATA_CBL_PATA40_SHORT;
}
ide_port_for_each_dev(i, drive, hwif)
ide_dev_apply_params(drive, i);
}
/*
* This is gets invoked once during initialization, to set *everything* up
*/
static int __init ide_init(void)
{
int ret;
printk(KERN_INFO "Uniform Multi-Platform E-IDE driver\n");
ret = bus_register(&ide_bus_type);
if (ret < 0) {
printk(KERN_WARNING "IDE: bus_register error: %d\n", ret);
return ret;
}
ide_port_class = class_create(THIS_MODULE, "ide_port");
if (IS_ERR(ide_port_class)) {
ret = PTR_ERR(ide_port_class);
goto out_port_class;
}
ide_acpi_init();
proc_ide_create();
return 0;
out_port_class:
bus_unregister(&ide_bus_type);
return ret;
}
static void __exit ide_exit(void)
{
proc_ide_destroy();
class_destroy(ide_port_class);
bus_unregister(&ide_bus_type);
}
module_init(ide_init);
module_exit(ide_exit);
MODULE_LICENSE("GPL");