linux/drivers/s390/cio/ioasm.c
Peter Oberparleiter 7775913724 s390/chsc: Add exception handler for CHSC instruction
Prevent kernel crashes due to unhandled exceptions raised by the CHSC
instruction which may for example be triggered by invalid ioctl data.

Fixes: 64150adf89 ("s390/cio: Introduce generic synchronous CHSC IOCTL")
Cc: <stable@vger.kernel.org> # v3.11+
Signed-off-by: Peter Oberparleiter <oberpar@linux.vnet.ibm.com>
Reviewed-by: Sebastian Ott <sebott@linux.vnet.ibm.com>
Reviewed-by: Cornelia Huck <cornelia.huck@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2017-02-23 10:06:38 +01:00

300 lines
4.8 KiB
C

/*
* Channel subsystem I/O instructions.
*/
#include <linux/export.h>
#include <asm/chpid.h>
#include <asm/schid.h>
#include <asm/crw.h>
#include "ioasm.h"
#include "orb.h"
#include "cio.h"
static inline int __stsch(struct subchannel_id schid, struct schib *addr)
{
register struct subchannel_id reg1 asm ("1") = schid;
int ccode = -EIO;
asm volatile(
" stsch 0(%3)\n"
"0: ipm %0\n"
" srl %0,28\n"
"1:\n"
EX_TABLE(0b, 1b)
: "+d" (ccode), "=m" (*addr)
: "d" (reg1), "a" (addr)
: "cc");
return ccode;
}
int stsch(struct subchannel_id schid, struct schib *addr)
{
int ccode;
ccode = __stsch(schid, addr);
trace_s390_cio_stsch(schid, addr, ccode);
return ccode;
}
EXPORT_SYMBOL(stsch);
static inline int __msch(struct subchannel_id schid, struct schib *addr)
{
register struct subchannel_id reg1 asm ("1") = schid;
int ccode = -EIO;
asm volatile(
" msch 0(%2)\n"
"0: ipm %0\n"
" srl %0,28\n"
"1:\n"
EX_TABLE(0b, 1b)
: "+d" (ccode)
: "d" (reg1), "a" (addr), "m" (*addr)
: "cc");
return ccode;
}
int msch(struct subchannel_id schid, struct schib *addr)
{
int ccode;
ccode = __msch(schid, addr);
trace_s390_cio_msch(schid, addr, ccode);
return ccode;
}
static inline int __tsch(struct subchannel_id schid, struct irb *addr)
{
register struct subchannel_id reg1 asm ("1") = schid;
int ccode;
asm volatile(
" tsch 0(%3)\n"
" ipm %0\n"
" srl %0,28"
: "=d" (ccode), "=m" (*addr)
: "d" (reg1), "a" (addr)
: "cc");
return ccode;
}
int tsch(struct subchannel_id schid, struct irb *addr)
{
int ccode;
ccode = __tsch(schid, addr);
trace_s390_cio_tsch(schid, addr, ccode);
return ccode;
}
static inline int __ssch(struct subchannel_id schid, union orb *addr)
{
register struct subchannel_id reg1 asm("1") = schid;
int ccode = -EIO;
asm volatile(
" ssch 0(%2)\n"
"0: ipm %0\n"
" srl %0,28\n"
"1:\n"
EX_TABLE(0b, 1b)
: "+d" (ccode)
: "d" (reg1), "a" (addr), "m" (*addr)
: "cc", "memory");
return ccode;
}
int ssch(struct subchannel_id schid, union orb *addr)
{
int ccode;
ccode = __ssch(schid, addr);
trace_s390_cio_ssch(schid, addr, ccode);
return ccode;
}
EXPORT_SYMBOL(ssch);
static inline int __csch(struct subchannel_id schid)
{
register struct subchannel_id reg1 asm("1") = schid;
int ccode;
asm volatile(
" csch\n"
" ipm %0\n"
" srl %0,28"
: "=d" (ccode)
: "d" (reg1)
: "cc");
return ccode;
}
int csch(struct subchannel_id schid)
{
int ccode;
ccode = __csch(schid);
trace_s390_cio_csch(schid, ccode);
return ccode;
}
EXPORT_SYMBOL(csch);
int tpi(struct tpi_info *addr)
{
int ccode;
asm volatile(
" tpi 0(%2)\n"
" ipm %0\n"
" srl %0,28"
: "=d" (ccode), "=m" (*addr)
: "a" (addr)
: "cc");
trace_s390_cio_tpi(addr, ccode);
return ccode;
}
int chsc(void *chsc_area)
{
typedef struct { char _[4096]; } addr_type;
int cc = -EIO;
asm volatile(
" .insn rre,0xb25f0000,%2,0\n"
"0: ipm %0\n"
" srl %0,28\n"
"1:\n"
EX_TABLE(0b, 1b)
: "+d" (cc), "=m" (*(addr_type *) chsc_area)
: "d" (chsc_area), "m" (*(addr_type *) chsc_area)
: "cc");
trace_s390_cio_chsc(chsc_area, cc);
return cc;
}
EXPORT_SYMBOL(chsc);
static inline int __rchp(struct chp_id chpid)
{
register struct chp_id reg1 asm ("1") = chpid;
int ccode;
asm volatile(
" lr 1,%1\n"
" rchp\n"
" ipm %0\n"
" srl %0,28"
: "=d" (ccode) : "d" (reg1) : "cc");
return ccode;
}
int rchp(struct chp_id chpid)
{
int ccode;
ccode = __rchp(chpid);
trace_s390_cio_rchp(chpid, ccode);
return ccode;
}
static inline int __rsch(struct subchannel_id schid)
{
register struct subchannel_id reg1 asm("1") = schid;
int ccode;
asm volatile(
" rsch\n"
" ipm %0\n"
" srl %0,28"
: "=d" (ccode)
: "d" (reg1)
: "cc", "memory");
return ccode;
}
int rsch(struct subchannel_id schid)
{
int ccode;
ccode = __rsch(schid);
trace_s390_cio_rsch(schid, ccode);
return ccode;
}
static inline int __hsch(struct subchannel_id schid)
{
register struct subchannel_id reg1 asm("1") = schid;
int ccode;
asm volatile(
" hsch\n"
" ipm %0\n"
" srl %0,28"
: "=d" (ccode)
: "d" (reg1)
: "cc");
return ccode;
}
int hsch(struct subchannel_id schid)
{
int ccode;
ccode = __hsch(schid);
trace_s390_cio_hsch(schid, ccode);
return ccode;
}
static inline int __xsch(struct subchannel_id schid)
{
register struct subchannel_id reg1 asm("1") = schid;
int ccode;
asm volatile(
" xsch\n"
" ipm %0\n"
" srl %0,28"
: "=d" (ccode)
: "d" (reg1)
: "cc");
return ccode;
}
int xsch(struct subchannel_id schid)
{
int ccode;
ccode = __xsch(schid);
trace_s390_cio_xsch(schid, ccode);
return ccode;
}
int stcrw(struct crw *crw)
{
int ccode;
asm volatile(
" stcrw 0(%2)\n"
" ipm %0\n"
" srl %0,28\n"
: "=d" (ccode), "=m" (*crw)
: "a" (crw)
: "cc");
trace_s390_cio_stcrw(crw, ccode);
return ccode;
}