android_kernel_motorola_sm6225/drivers/pnp/pnpbios/bioscalls.c
Zachary Amsden 5fe9fe3c6f [PATCH] x86: Pnp byte granularity
The one remaining caller of set_limit, the PnP BIOS code, calls into the PnP
BIOS, passing kernel parameters in and out.  These parameteres may be passed
from arbitrary kernel virtual memory, so they deserve strict protection to
stop a bad BIOS from smashing beyond the object size.

Unfortunately, the use of set_limit was badly botching this by setting the
limit in terms of pages, when it really should have byte granularity.

When doing this, I discovered my BIOS had the buggy code during the "get
system device node" call:

 mov ax, es:[bx]

Which is harmless, but has a trivial workaround.

Signed-off-by: Zachary Amsden <zach@vmware.com>
Cc: "Seth, Rohit" <rohit.seth@intel.com>
Cc: Stephen Rothwell <sfr@canb.auug.org.au>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-01-06 08:33:35 -08:00

542 lines
14 KiB
C

/*
* bioscalls.c - the lowlevel layer of the PnPBIOS driver
*
*/
#include <linux/types.h>
#include <linux/module.h>
#include <linux/init.h>
#include <linux/linkage.h>
#include <linux/kernel.h>
#include <linux/pnpbios.h>
#include <linux/device.h>
#include <linux/pnp.h>
#include <linux/mm.h>
#include <linux/smp.h>
#include <linux/slab.h>
#include <linux/kmod.h>
#include <linux/completion.h>
#include <linux/spinlock.h>
#include <asm/page.h>
#include <asm/desc.h>
#include <asm/system.h>
#include <asm/byteorder.h>
#include "pnpbios.h"
static struct {
u16 offset;
u16 segment;
} pnp_bios_callpoint;
/*
* These are some opcodes for a "static asmlinkage"
* As this code is *not* executed inside the linux kernel segment, but in a
* alias at offset 0, we need a far return that can not be compiled by
* default (please, prove me wrong! this is *really* ugly!)
* This is the only way to get the bios to return into the kernel code,
* because the bios code runs in 16 bit protected mode and therefore can only
* return to the caller if the call is within the first 64kB, and the linux
* kernel begins at offset 3GB...
*/
asmlinkage void pnp_bios_callfunc(void);
__asm__(
".text \n"
__ALIGN_STR "\n"
"pnp_bios_callfunc:\n"
" pushl %edx \n"
" pushl %ecx \n"
" pushl %ebx \n"
" pushl %eax \n"
" lcallw *pnp_bios_callpoint\n"
" addl $16, %esp \n"
" lret \n"
".previous \n"
);
#define Q_SET_SEL(cpu, selname, address, size) \
do { \
struct desc_struct *gdt = get_cpu_gdt_table((cpu)); \
set_base(gdt[(selname) >> 3], __va((u32)(address))); \
set_limit(gdt[(selname) >> 3], size); \
} while(0)
#define Q2_SET_SEL(cpu, selname, address, size) \
do { \
struct desc_struct *gdt = get_cpu_gdt_table((cpu)); \
set_base(gdt[(selname) >> 3], (u32)(address)); \
set_limit(gdt[(selname) >> 3], size); \
} while(0)
static struct desc_struct bad_bios_desc = { 0, 0x00409200 };
/*
* At some point we want to use this stack frame pointer to unwind
* after PnP BIOS oopses.
*/
u32 pnp_bios_fault_esp;
u32 pnp_bios_fault_eip;
u32 pnp_bios_is_utter_crap = 0;
static spinlock_t pnp_bios_lock;
/*
* Support Functions
*/
static inline u16 call_pnp_bios(u16 func, u16 arg1, u16 arg2, u16 arg3,
u16 arg4, u16 arg5, u16 arg6, u16 arg7,
void *ts1_base, u32 ts1_size,
void *ts2_base, u32 ts2_size)
{
unsigned long flags;
u16 status;
struct desc_struct save_desc_40;
int cpu;
/*
* PnP BIOSes are generally not terribly re-entrant.
* Also, don't rely on them to save everything correctly.
*/
if(pnp_bios_is_utter_crap)
return PNP_FUNCTION_NOT_SUPPORTED;
cpu = get_cpu();
save_desc_40 = get_cpu_gdt_table(cpu)[0x40 / 8];
get_cpu_gdt_table(cpu)[0x40 / 8] = bad_bios_desc;
/* On some boxes IRQ's during PnP BIOS calls are deadly. */
spin_lock_irqsave(&pnp_bios_lock, flags);
/* The lock prevents us bouncing CPU here */
if (ts1_size)
Q2_SET_SEL(smp_processor_id(), PNP_TS1, ts1_base, ts1_size);
if (ts2_size)
Q2_SET_SEL(smp_processor_id(), PNP_TS2, ts2_base, ts2_size);
__asm__ __volatile__(
"pushl %%ebp\n\t"
"pushl %%edi\n\t"
"pushl %%esi\n\t"
"pushl %%ds\n\t"
"pushl %%es\n\t"
"pushl %%fs\n\t"
"pushl %%gs\n\t"
"pushfl\n\t"
"movl %%esp, pnp_bios_fault_esp\n\t"
"movl $1f, pnp_bios_fault_eip\n\t"
"lcall %5,%6\n\t"
"1:popfl\n\t"
"popl %%gs\n\t"
"popl %%fs\n\t"
"popl %%es\n\t"
"popl %%ds\n\t"
"popl %%esi\n\t"
"popl %%edi\n\t"
"popl %%ebp\n\t"
: "=a" (status)
: "0" ((func) | (((u32)arg1) << 16)),
"b" ((arg2) | (((u32)arg3) << 16)),
"c" ((arg4) | (((u32)arg5) << 16)),
"d" ((arg6) | (((u32)arg7) << 16)),
"i" (PNP_CS32),
"i" (0)
: "memory"
);
spin_unlock_irqrestore(&pnp_bios_lock, flags);
get_cpu_gdt_table(cpu)[0x40 / 8] = save_desc_40;
put_cpu();
/* If we get here and this is set then the PnP BIOS faulted on us. */
if(pnp_bios_is_utter_crap)
{
printk(KERN_ERR "PnPBIOS: Warning! Your PnP BIOS caused a fatal error. Attempting to continue\n");
printk(KERN_ERR "PnPBIOS: You may need to reboot with the \"pnpbios=off\" option to operate stably\n");
printk(KERN_ERR "PnPBIOS: Check with your vendor for an updated BIOS\n");
}
return status;
}
void pnpbios_print_status(const char * module, u16 status)
{
switch(status) {
case PNP_SUCCESS:
printk(KERN_ERR "PnPBIOS: %s: function successful\n", module);
break;
case PNP_NOT_SET_STATICALLY:
printk(KERN_ERR "PnPBIOS: %s: unable to set static resources\n", module);
break;
case PNP_UNKNOWN_FUNCTION:
printk(KERN_ERR "PnPBIOS: %s: invalid function number passed\n", module);
break;
case PNP_FUNCTION_NOT_SUPPORTED:
printk(KERN_ERR "PnPBIOS: %s: function not supported on this system\n", module);
break;
case PNP_INVALID_HANDLE:
printk(KERN_ERR "PnPBIOS: %s: invalid handle\n", module);
break;
case PNP_BAD_PARAMETER:
printk(KERN_ERR "PnPBIOS: %s: invalid parameters were passed\n", module);
break;
case PNP_SET_FAILED:
printk(KERN_ERR "PnPBIOS: %s: unable to set resources\n", module);
break;
case PNP_EVENTS_NOT_PENDING:
printk(KERN_ERR "PnPBIOS: %s: no events are pending\n", module);
break;
case PNP_SYSTEM_NOT_DOCKED:
printk(KERN_ERR "PnPBIOS: %s: the system is not docked\n", module);
break;
case PNP_NO_ISA_PNP_CARDS:
printk(KERN_ERR "PnPBIOS: %s: no isapnp cards are installed on this system\n", module);
break;
case PNP_UNABLE_TO_DETERMINE_DOCK_CAPABILITIES:
printk(KERN_ERR "PnPBIOS: %s: cannot determine the capabilities of the docking station\n", module);
break;
case PNP_CONFIG_CHANGE_FAILED_NO_BATTERY:
printk(KERN_ERR "PnPBIOS: %s: unable to undock, the system does not have a battery\n", module);
break;
case PNP_CONFIG_CHANGE_FAILED_RESOURCE_CONFLICT:
printk(KERN_ERR "PnPBIOS: %s: could not dock due to resource conflicts\n", module);
break;
case PNP_BUFFER_TOO_SMALL:
printk(KERN_ERR "PnPBIOS: %s: the buffer passed is too small\n", module);
break;
case PNP_USE_ESCD_SUPPORT:
printk(KERN_ERR "PnPBIOS: %s: use ESCD instead\n", module);
break;
case PNP_MESSAGE_NOT_SUPPORTED:
printk(KERN_ERR "PnPBIOS: %s: the message is unsupported\n", module);
break;
case PNP_HARDWARE_ERROR:
printk(KERN_ERR "PnPBIOS: %s: a hardware failure has occured\n", module);
break;
default:
printk(KERN_ERR "PnPBIOS: %s: unexpected status 0x%x\n", module, status);
break;
}
}
/*
* PnP BIOS Low Level Calls
*/
#define PNP_GET_NUM_SYS_DEV_NODES 0x00
#define PNP_GET_SYS_DEV_NODE 0x01
#define PNP_SET_SYS_DEV_NODE 0x02
#define PNP_GET_EVENT 0x03
#define PNP_SEND_MESSAGE 0x04
#define PNP_GET_DOCKING_STATION_INFORMATION 0x05
#define PNP_SET_STATIC_ALLOCED_RES_INFO 0x09
#define PNP_GET_STATIC_ALLOCED_RES_INFO 0x0a
#define PNP_GET_APM_ID_TABLE 0x0b
#define PNP_GET_PNP_ISA_CONFIG_STRUC 0x40
#define PNP_GET_ESCD_INFO 0x41
#define PNP_READ_ESCD 0x42
#define PNP_WRITE_ESCD 0x43
/*
* Call PnP BIOS with function 0x00, "get number of system device nodes"
*/
static int __pnp_bios_dev_node_info(struct pnp_dev_node_info *data)
{
u16 status;
if (!pnp_bios_present())
return PNP_FUNCTION_NOT_SUPPORTED;
status = call_pnp_bios(PNP_GET_NUM_SYS_DEV_NODES, 0, PNP_TS1, 2, PNP_TS1, PNP_DS, 0, 0,
data, sizeof(struct pnp_dev_node_info), NULL, 0);
data->no_nodes &= 0xff;
return status;
}
int pnp_bios_dev_node_info(struct pnp_dev_node_info *data)
{
int status = __pnp_bios_dev_node_info( data );
if ( status )
pnpbios_print_status( "dev_node_info", status );
return status;
}
/*
* Note that some PnP BIOSes (e.g., on Sony Vaio laptops) die a horrible
* death if they are asked to access the "current" configuration.
* Therefore, if it's a matter of indifference, it's better to call
* get_dev_node() and set_dev_node() with boot=1 rather than with boot=0.
*/
/*
* Call PnP BIOS with function 0x01, "get system device node"
* Input: *nodenum = desired node,
* boot = whether to get nonvolatile boot (!=0)
* or volatile current (0) config
* Output: *nodenum=next node or 0xff if no more nodes
*/
static int __pnp_bios_get_dev_node(u8 *nodenum, char boot, struct pnp_bios_node *data)
{
u16 status;
u16 tmp_nodenum;
if (!pnp_bios_present())
return PNP_FUNCTION_NOT_SUPPORTED;
if ( !boot && pnpbios_dont_use_current_config )
return PNP_FUNCTION_NOT_SUPPORTED;
tmp_nodenum = *nodenum;
status = call_pnp_bios(PNP_GET_SYS_DEV_NODE, 0, PNP_TS1, 0, PNP_TS2, boot ? 2 : 1, PNP_DS, 0,
&tmp_nodenum, sizeof(tmp_nodenum), data, 65536);
*nodenum = tmp_nodenum;
return status;
}
int pnp_bios_get_dev_node(u8 *nodenum, char boot, struct pnp_bios_node *data)
{
int status;
status = __pnp_bios_get_dev_node( nodenum, boot, data );
if ( status )
pnpbios_print_status( "get_dev_node", status );
return status;
}
/*
* Call PnP BIOS with function 0x02, "set system device node"
* Input: *nodenum = desired node,
* boot = whether to set nonvolatile boot (!=0)
* or volatile current (0) config
*/
static int __pnp_bios_set_dev_node(u8 nodenum, char boot, struct pnp_bios_node *data)
{
u16 status;
if (!pnp_bios_present())
return PNP_FUNCTION_NOT_SUPPORTED;
if ( !boot && pnpbios_dont_use_current_config )
return PNP_FUNCTION_NOT_SUPPORTED;
status = call_pnp_bios(PNP_SET_SYS_DEV_NODE, nodenum, 0, PNP_TS1, boot ? 2 : 1, PNP_DS, 0, 0,
data, 65536, NULL, 0);
return status;
}
int pnp_bios_set_dev_node(u8 nodenum, char boot, struct pnp_bios_node *data)
{
int status;
status = __pnp_bios_set_dev_node( nodenum, boot, data );
if ( status ) {
pnpbios_print_status( "set_dev_node", status );
return status;
}
if ( !boot ) { /* Update devlist */
status = pnp_bios_get_dev_node( &nodenum, boot, data );
if ( status )
return status;
}
return status;
}
#if needed
/*
* Call PnP BIOS with function 0x03, "get event"
*/
static int pnp_bios_get_event(u16 *event)
{
u16 status;
if (!pnp_bios_present())
return PNP_FUNCTION_NOT_SUPPORTED;
status = call_pnp_bios(PNP_GET_EVENT, 0, PNP_TS1, PNP_DS, 0, 0 ,0 ,0,
event, sizeof(u16), NULL, 0);
return status;
}
#endif
#if needed
/*
* Call PnP BIOS with function 0x04, "send message"
*/
static int pnp_bios_send_message(u16 message)
{
u16 status;
if (!pnp_bios_present())
return PNP_FUNCTION_NOT_SUPPORTED;
status = call_pnp_bios(PNP_SEND_MESSAGE, message, PNP_DS, 0, 0, 0, 0, 0, 0, 0, 0, 0);
return status;
}
#endif
/*
* Call PnP BIOS with function 0x05, "get docking station information"
*/
int pnp_bios_dock_station_info(struct pnp_docking_station_info *data)
{
u16 status;
if (!pnp_bios_present())
return PNP_FUNCTION_NOT_SUPPORTED;
status = call_pnp_bios(PNP_GET_DOCKING_STATION_INFORMATION, 0, PNP_TS1, PNP_DS, 0, 0, 0, 0,
data, sizeof(struct pnp_docking_station_info), NULL, 0);
return status;
}
#if needed
/*
* Call PnP BIOS with function 0x09, "set statically allocated resource
* information"
*/
static int pnp_bios_set_stat_res(char *info)
{
u16 status;
if (!pnp_bios_present())
return PNP_FUNCTION_NOT_SUPPORTED;
status = call_pnp_bios(PNP_SET_STATIC_ALLOCED_RES_INFO, 0, PNP_TS1, PNP_DS, 0, 0, 0, 0,
info, *((u16 *) info), 0, 0);
return status;
}
#endif
/*
* Call PnP BIOS with function 0x0a, "get statically allocated resource
* information"
*/
static int __pnp_bios_get_stat_res(char *info)
{
u16 status;
if (!pnp_bios_present())
return PNP_FUNCTION_NOT_SUPPORTED;
status = call_pnp_bios(PNP_GET_STATIC_ALLOCED_RES_INFO, 0, PNP_TS1, PNP_DS, 0, 0, 0, 0,
info, 65536, NULL, 0);
return status;
}
int pnp_bios_get_stat_res(char *info)
{
int status;
status = __pnp_bios_get_stat_res( info );
if ( status )
pnpbios_print_status( "get_stat_res", status );
return status;
}
#if needed
/*
* Call PnP BIOS with function 0x0b, "get APM id table"
*/
static int pnp_bios_apm_id_table(char *table, u16 *size)
{
u16 status;
if (!pnp_bios_present())
return PNP_FUNCTION_NOT_SUPPORTED;
status = call_pnp_bios(PNP_GET_APM_ID_TABLE, 0, PNP_TS2, 0, PNP_TS1, PNP_DS, 0, 0,
table, *size, size, sizeof(u16));
return status;
}
#endif
/*
* Call PnP BIOS with function 0x40, "get isa pnp configuration structure"
*/
static int __pnp_bios_isapnp_config(struct pnp_isa_config_struc *data)
{
u16 status;
if (!pnp_bios_present())
return PNP_FUNCTION_NOT_SUPPORTED;
status = call_pnp_bios(PNP_GET_PNP_ISA_CONFIG_STRUC, 0, PNP_TS1, PNP_DS, 0, 0, 0, 0,
data, sizeof(struct pnp_isa_config_struc), NULL, 0);
return status;
}
int pnp_bios_isapnp_config(struct pnp_isa_config_struc *data)
{
int status;
status = __pnp_bios_isapnp_config( data );
if ( status )
pnpbios_print_status( "isapnp_config", status );
return status;
}
/*
* Call PnP BIOS with function 0x41, "get ESCD info"
*/
static int __pnp_bios_escd_info(struct escd_info_struc *data)
{
u16 status;
if (!pnp_bios_present())
return ESCD_FUNCTION_NOT_SUPPORTED;
status = call_pnp_bios(PNP_GET_ESCD_INFO, 0, PNP_TS1, 2, PNP_TS1, 4, PNP_TS1, PNP_DS,
data, sizeof(struct escd_info_struc), NULL, 0);
return status;
}
int pnp_bios_escd_info(struct escd_info_struc *data)
{
int status;
status = __pnp_bios_escd_info( data );
if ( status )
pnpbios_print_status( "escd_info", status );
return status;
}
/*
* Call PnP BIOS function 0x42, "read ESCD"
* nvram_base is determined by calling escd_info
*/
static int __pnp_bios_read_escd(char *data, u32 nvram_base)
{
u16 status;
if (!pnp_bios_present())
return ESCD_FUNCTION_NOT_SUPPORTED;
status = call_pnp_bios(PNP_READ_ESCD, 0, PNP_TS1, PNP_TS2, PNP_DS, 0, 0, 0,
data, 65536, __va(nvram_base), 65536);
return status;
}
int pnp_bios_read_escd(char *data, u32 nvram_base)
{
int status;
status = __pnp_bios_read_escd( data, nvram_base );
if ( status )
pnpbios_print_status( "read_escd", status );
return status;
}
#if needed
/*
* Call PnP BIOS function 0x43, "write ESCD"
*/
static int pnp_bios_write_escd(char *data, u32 nvram_base)
{
u16 status;
if (!pnp_bios_present())
return ESCD_FUNCTION_NOT_SUPPORTED;
status = call_pnp_bios(PNP_WRITE_ESCD, 0, PNP_TS1, PNP_TS2, PNP_DS, 0, 0, 0,
data, 65536, __va(nvram_base), 65536);
return status;
}
#endif
/*
* Initialization
*/
void pnpbios_calls_init(union pnp_bios_install_struct *header)
{
int i;
spin_lock_init(&pnp_bios_lock);
pnp_bios_callpoint.offset = header->fields.pm16offset;
pnp_bios_callpoint.segment = PNP_CS16;
set_base(bad_bios_desc, __va((unsigned long)0x40 << 4));
_set_limit((char *)&bad_bios_desc, 4095 - (0x40 << 4));
for (i = 0; i < NR_CPUS; i++) {
struct desc_struct *gdt = get_cpu_gdt_table(i);
if (!gdt)
continue;
Q2_SET_SEL(i, PNP_CS32, &pnp_bios_callfunc, 64 * 1024);
Q_SET_SEL(i, PNP_CS16, header->fields.pm16cseg, 64 * 1024);
Q_SET_SEL(i, PNP_DS, header->fields.pm16dseg, 64 * 1024);
}
}