linux/arch/s390/mm/extmem.c
Heiko Carstens a53c8fab3f s390/comments: unify copyright messages and remove file names
Remove the file name from the comment at top of many files. In most
cases the file name was wrong anyway, so it's rather pointless.

Also unify the IBM copyright statement. We did have a lot of sightly
different statements and wanted to change them one after another
whenever a file gets touched. However that never happened. Instead
people start to take the old/"wrong" statements to use as a template
for new files.
So unify all of them in one go.

Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
2012-07-20 11:15:04 +02:00

777 lines
18 KiB
C

/*
* Author(s)......: Carsten Otte <cotte@de.ibm.com>
* Rob M van der Heij <rvdheij@nl.ibm.com>
* Steven Shultz <shultzss@us.ibm.com>
* Bugreports.to..: <Linux390@de.ibm.com>
* Copyright IBM Corp. 2002, 2004
*/
#define KMSG_COMPONENT "extmem"
#define pr_fmt(fmt) KMSG_COMPONENT ": " fmt
#include <linux/kernel.h>
#include <linux/string.h>
#include <linux/spinlock.h>
#include <linux/list.h>
#include <linux/slab.h>
#include <linux/module.h>
#include <linux/bootmem.h>
#include <linux/ctype.h>
#include <linux/ioport.h>
#include <asm/page.h>
#include <asm/pgtable.h>
#include <asm/ebcdic.h>
#include <asm/errno.h>
#include <asm/extmem.h>
#include <asm/cpcmd.h>
#include <asm/setup.h>
#define DCSS_LOADSHR 0x00
#define DCSS_LOADNSR 0x04
#define DCSS_PURGESEG 0x08
#define DCSS_FINDSEG 0x0c
#define DCSS_LOADNOLY 0x10
#define DCSS_SEGEXT 0x18
#define DCSS_LOADSHRX 0x20
#define DCSS_LOADNSRX 0x24
#define DCSS_FINDSEGX 0x2c
#define DCSS_SEGEXTX 0x38
#define DCSS_FINDSEGA 0x0c
struct qrange {
unsigned long start; /* last byte type */
unsigned long end; /* last byte reserved */
};
struct qout64 {
unsigned long segstart;
unsigned long segend;
int segcnt;
int segrcnt;
struct qrange range[6];
};
#ifdef CONFIG_64BIT
struct qrange_old {
unsigned int start; /* last byte type */
unsigned int end; /* last byte reserved */
};
/* output area format for the Diag x'64' old subcode x'18' */
struct qout64_old {
int segstart;
int segend;
int segcnt;
int segrcnt;
struct qrange_old range[6];
};
#endif
struct qin64 {
char qopcode;
char rsrv1[3];
char qrcode;
char rsrv2[3];
char qname[8];
unsigned int qoutptr;
short int qoutlen;
};
struct dcss_segment {
struct list_head list;
char dcss_name[8];
char res_name[15];
unsigned long start_addr;
unsigned long end;
atomic_t ref_count;
int do_nonshared;
unsigned int vm_segtype;
struct qrange range[6];
int segcnt;
struct resource *res;
};
static DEFINE_MUTEX(dcss_lock);
static LIST_HEAD(dcss_list);
static char *segtype_string[] = { "SW", "EW", "SR", "ER", "SN", "EN", "SC",
"EW/EN-MIXED" };
static int loadshr_scode, loadnsr_scode, findseg_scode;
static int segext_scode, purgeseg_scode;
static int scode_set;
/* set correct Diag x'64' subcodes. */
static int
dcss_set_subcodes(void)
{
#ifdef CONFIG_64BIT
char *name = kmalloc(8 * sizeof(char), GFP_KERNEL | GFP_DMA);
unsigned long rx, ry;
int rc;
if (name == NULL)
return -ENOMEM;
rx = (unsigned long) name;
ry = DCSS_FINDSEGX;
strcpy(name, "dummy");
asm volatile(
" diag %0,%1,0x64\n"
"0: ipm %2\n"
" srl %2,28\n"
" j 2f\n"
"1: la %2,3\n"
"2:\n"
EX_TABLE(0b, 1b)
: "+d" (rx), "+d" (ry), "=d" (rc) : : "cc");
kfree(name);
/* Diag x'64' new subcodes are supported, set to new subcodes */
if (rc != 3) {
loadshr_scode = DCSS_LOADSHRX;
loadnsr_scode = DCSS_LOADNSRX;
purgeseg_scode = DCSS_PURGESEG;
findseg_scode = DCSS_FINDSEGX;
segext_scode = DCSS_SEGEXTX;
return 0;
}
#endif
/* Diag x'64' new subcodes are not supported, set to old subcodes */
loadshr_scode = DCSS_LOADNOLY;
loadnsr_scode = DCSS_LOADNSR;
purgeseg_scode = DCSS_PURGESEG;
findseg_scode = DCSS_FINDSEG;
segext_scode = DCSS_SEGEXT;
return 0;
}
/*
* Create the 8 bytes, ebcdic VM segment name from
* an ascii name.
*/
static void
dcss_mkname(char *name, char *dcss_name)
{
int i;
for (i = 0; i < 8; i++) {
if (name[i] == '\0')
break;
dcss_name[i] = toupper(name[i]);
};
for (; i < 8; i++)
dcss_name[i] = ' ';
ASCEBC(dcss_name, 8);
}
/*
* search all segments in dcss_list, and return the one
* namend *name. If not found, return NULL.
*/
static struct dcss_segment *
segment_by_name (char *name)
{
char dcss_name[9];
struct list_head *l;
struct dcss_segment *tmp, *retval = NULL;
BUG_ON(!mutex_is_locked(&dcss_lock));
dcss_mkname (name, dcss_name);
list_for_each (l, &dcss_list) {
tmp = list_entry (l, struct dcss_segment, list);
if (memcmp(tmp->dcss_name, dcss_name, 8) == 0) {
retval = tmp;
break;
}
}
return retval;
}
/*
* Perform a function on a dcss segment.
*/
static inline int
dcss_diag(int *func, void *parameter,
unsigned long *ret1, unsigned long *ret2)
{
unsigned long rx, ry;
int rc;
if (scode_set == 0) {
rc = dcss_set_subcodes();
if (rc < 0)
return rc;
scode_set = 1;
}
rx = (unsigned long) parameter;
ry = (unsigned long) *func;
#ifdef CONFIG_64BIT
/* 64-bit Diag x'64' new subcode, keep in 64-bit addressing mode */
if (*func > DCSS_SEGEXT)
asm volatile(
" diag %0,%1,0x64\n"
" ipm %2\n"
" srl %2,28\n"
: "+d" (rx), "+d" (ry), "=d" (rc) : : "cc");
/* 31-bit Diag x'64' old subcode, switch to 31-bit addressing mode */
else
asm volatile(
" sam31\n"
" diag %0,%1,0x64\n"
" sam64\n"
" ipm %2\n"
" srl %2,28\n"
: "+d" (rx), "+d" (ry), "=d" (rc) : : "cc");
#else
asm volatile(
" diag %0,%1,0x64\n"
" ipm %2\n"
" srl %2,28\n"
: "+d" (rx), "+d" (ry), "=d" (rc) : : "cc");
#endif
*ret1 = rx;
*ret2 = ry;
return rc;
}
static inline int
dcss_diag_translate_rc (int vm_rc) {
if (vm_rc == 44)
return -ENOENT;
return -EIO;
}
/* do a diag to get info about a segment.
* fills start_address, end and vm_segtype fields
*/
static int
query_segment_type (struct dcss_segment *seg)
{
unsigned long dummy, vmrc;
int diag_cc, rc, i;
struct qout64 *qout;
struct qin64 *qin;
qin = kmalloc(sizeof(*qin), GFP_KERNEL | GFP_DMA);
qout = kmalloc(sizeof(*qout), GFP_KERNEL | GFP_DMA);
if ((qin == NULL) || (qout == NULL)) {
rc = -ENOMEM;
goto out_free;
}
/* initialize diag input parameters */
qin->qopcode = DCSS_FINDSEGA;
qin->qoutptr = (unsigned long) qout;
qin->qoutlen = sizeof(struct qout64);
memcpy (qin->qname, seg->dcss_name, 8);
diag_cc = dcss_diag(&segext_scode, qin, &dummy, &vmrc);
if (diag_cc < 0) {
rc = diag_cc;
goto out_free;
}
if (diag_cc > 1) {
pr_warning("Querying a DCSS type failed with rc=%ld\n", vmrc);
rc = dcss_diag_translate_rc (vmrc);
goto out_free;
}
#ifdef CONFIG_64BIT
/* Only old format of output area of Diagnose x'64' is supported,
copy data for the new format. */
if (segext_scode == DCSS_SEGEXT) {
struct qout64_old *qout_old;
qout_old = kzalloc(sizeof(*qout_old), GFP_KERNEL | GFP_DMA);
if (qout_old == NULL) {
rc = -ENOMEM;
goto out_free;
}
memcpy(qout_old, qout, sizeof(struct qout64_old));
qout->segstart = (unsigned long) qout_old->segstart;
qout->segend = (unsigned long) qout_old->segend;
qout->segcnt = qout_old->segcnt;
qout->segrcnt = qout_old->segrcnt;
if (qout->segcnt > 6)
qout->segrcnt = 6;
for (i = 0; i < qout->segrcnt; i++) {
qout->range[i].start =
(unsigned long) qout_old->range[i].start;
qout->range[i].end =
(unsigned long) qout_old->range[i].end;
}
kfree(qout_old);
}
#endif
if (qout->segcnt > 6) {
rc = -EOPNOTSUPP;
goto out_free;
}
if (qout->segcnt == 1) {
seg->vm_segtype = qout->range[0].start & 0xff;
} else {
/* multi-part segment. only one type supported here:
- all parts are contiguous
- all parts are either EW or EN type
- maximum 6 parts allowed */
unsigned long start = qout->segstart >> PAGE_SHIFT;
for (i=0; i<qout->segcnt; i++) {
if (((qout->range[i].start & 0xff) != SEG_TYPE_EW) &&
((qout->range[i].start & 0xff) != SEG_TYPE_EN)) {
rc = -EOPNOTSUPP;
goto out_free;
}
if (start != qout->range[i].start >> PAGE_SHIFT) {
rc = -EOPNOTSUPP;
goto out_free;
}
start = (qout->range[i].end >> PAGE_SHIFT) + 1;
}
seg->vm_segtype = SEG_TYPE_EWEN;
}
/* analyze diag output and update seg */
seg->start_addr = qout->segstart;
seg->end = qout->segend;
memcpy (seg->range, qout->range, 6*sizeof(struct qrange));
seg->segcnt = qout->segcnt;
rc = 0;
out_free:
kfree(qin);
kfree(qout);
return rc;
}
/*
* get info about a segment
* possible return values:
* -ENOSYS : we are not running on VM
* -EIO : could not perform query diagnose
* -ENOENT : no such segment
* -EOPNOTSUPP: multi-part segment cannot be used with linux
* -ENOMEM : out of memory
* 0 .. 6 : type of segment as defined in include/asm-s390/extmem.h
*/
int
segment_type (char* name)
{
int rc;
struct dcss_segment seg;
if (!MACHINE_IS_VM)
return -ENOSYS;
dcss_mkname(name, seg.dcss_name);
rc = query_segment_type (&seg);
if (rc < 0)
return rc;
return seg.vm_segtype;
}
/*
* check if segment collides with other segments that are currently loaded
* returns 1 if this is the case, 0 if no collision was found
*/
static int
segment_overlaps_others (struct dcss_segment *seg)
{
struct list_head *l;
struct dcss_segment *tmp;
BUG_ON(!mutex_is_locked(&dcss_lock));
list_for_each(l, &dcss_list) {
tmp = list_entry(l, struct dcss_segment, list);
if ((tmp->start_addr >> 20) > (seg->end >> 20))
continue;
if ((tmp->end >> 20) < (seg->start_addr >> 20))
continue;
if (seg == tmp)
continue;
return 1;
}
return 0;
}
/*
* real segment loading function, called from segment_load
*/
static int
__segment_load (char *name, int do_nonshared, unsigned long *addr, unsigned long *end)
{
unsigned long start_addr, end_addr, dummy;
struct dcss_segment *seg;
int rc, diag_cc;
start_addr = end_addr = 0;
seg = kmalloc(sizeof(*seg), GFP_KERNEL | GFP_DMA);
if (seg == NULL) {
rc = -ENOMEM;
goto out;
}
dcss_mkname (name, seg->dcss_name);
rc = query_segment_type (seg);
if (rc < 0)
goto out_free;
if (loadshr_scode == DCSS_LOADSHRX) {
if (segment_overlaps_others(seg)) {
rc = -EBUSY;
goto out_free;
}
}
rc = vmem_add_mapping(seg->start_addr, seg->end - seg->start_addr + 1);
if (rc)
goto out_free;
seg->res = kzalloc(sizeof(struct resource), GFP_KERNEL);
if (seg->res == NULL) {
rc = -ENOMEM;
goto out_shared;
}
seg->res->flags = IORESOURCE_BUSY | IORESOURCE_MEM;
seg->res->start = seg->start_addr;
seg->res->end = seg->end;
memcpy(&seg->res_name, seg->dcss_name, 8);
EBCASC(seg->res_name, 8);
seg->res_name[8] = '\0';
strncat(seg->res_name, " (DCSS)", 7);
seg->res->name = seg->res_name;
rc = seg->vm_segtype;
if (rc == SEG_TYPE_SC ||
((rc == SEG_TYPE_SR || rc == SEG_TYPE_ER) && !do_nonshared))
seg->res->flags |= IORESOURCE_READONLY;
if (request_resource(&iomem_resource, seg->res)) {
rc = -EBUSY;
kfree(seg->res);
goto out_shared;
}
if (do_nonshared)
diag_cc = dcss_diag(&loadnsr_scode, seg->dcss_name,
&start_addr, &end_addr);
else
diag_cc = dcss_diag(&loadshr_scode, seg->dcss_name,
&start_addr, &end_addr);
if (diag_cc < 0) {
dcss_diag(&purgeseg_scode, seg->dcss_name,
&dummy, &dummy);
rc = diag_cc;
goto out_resource;
}
if (diag_cc > 1) {
pr_warning("Loading DCSS %s failed with rc=%ld\n", name,
end_addr);
rc = dcss_diag_translate_rc(end_addr);
dcss_diag(&purgeseg_scode, seg->dcss_name,
&dummy, &dummy);
goto out_resource;
}
seg->start_addr = start_addr;
seg->end = end_addr;
seg->do_nonshared = do_nonshared;
atomic_set(&seg->ref_count, 1);
list_add(&seg->list, &dcss_list);
*addr = seg->start_addr;
*end = seg->end;
if (do_nonshared)
pr_info("DCSS %s of range %p to %p and type %s loaded as "
"exclusive-writable\n", name, (void*) seg->start_addr,
(void*) seg->end, segtype_string[seg->vm_segtype]);
else {
pr_info("DCSS %s of range %p to %p and type %s loaded in "
"shared access mode\n", name, (void*) seg->start_addr,
(void*) seg->end, segtype_string[seg->vm_segtype]);
}
goto out;
out_resource:
release_resource(seg->res);
kfree(seg->res);
out_shared:
vmem_remove_mapping(seg->start_addr, seg->end - seg->start_addr + 1);
out_free:
kfree(seg);
out:
return rc;
}
/*
* this function loads a DCSS segment
* name : name of the DCSS
* do_nonshared : 0 indicates that the dcss should be shared with other linux images
* 1 indicates that the dcss should be exclusive for this linux image
* addr : will be filled with start address of the segment
* end : will be filled with end address of the segment
* return values:
* -ENOSYS : we are not running on VM
* -EIO : could not perform query or load diagnose
* -ENOENT : no such segment
* -EOPNOTSUPP: multi-part segment cannot be used with linux
* -ENOSPC : segment cannot be used (overlaps with storage)
* -EBUSY : segment can temporarily not be used (overlaps with dcss)
* -ERANGE : segment cannot be used (exceeds kernel mapping range)
* -EPERM : segment is currently loaded with incompatible permissions
* -ENOMEM : out of memory
* 0 .. 6 : type of segment as defined in include/asm-s390/extmem.h
*/
int
segment_load (char *name, int do_nonshared, unsigned long *addr,
unsigned long *end)
{
struct dcss_segment *seg;
int rc;
if (!MACHINE_IS_VM)
return -ENOSYS;
mutex_lock(&dcss_lock);
seg = segment_by_name (name);
if (seg == NULL)
rc = __segment_load (name, do_nonshared, addr, end);
else {
if (do_nonshared == seg->do_nonshared) {
atomic_inc(&seg->ref_count);
*addr = seg->start_addr;
*end = seg->end;
rc = seg->vm_segtype;
} else {
*addr = *end = 0;
rc = -EPERM;
}
}
mutex_unlock(&dcss_lock);
return rc;
}
/*
* this function modifies the shared state of a DCSS segment. note that
* name : name of the DCSS
* do_nonshared : 0 indicates that the dcss should be shared with other linux images
* 1 indicates that the dcss should be exclusive for this linux image
* return values:
* -EIO : could not perform load diagnose (segment gone!)
* -ENOENT : no such segment (segment gone!)
* -EAGAIN : segment is in use by other exploiters, try later
* -EINVAL : no segment with the given name is currently loaded - name invalid
* -EBUSY : segment can temporarily not be used (overlaps with dcss)
* 0 : operation succeeded
*/
int
segment_modify_shared (char *name, int do_nonshared)
{
struct dcss_segment *seg;
unsigned long start_addr, end_addr, dummy;
int rc, diag_cc;
start_addr = end_addr = 0;
mutex_lock(&dcss_lock);
seg = segment_by_name (name);
if (seg == NULL) {
rc = -EINVAL;
goto out_unlock;
}
if (do_nonshared == seg->do_nonshared) {
pr_info("DCSS %s is already in the requested access "
"mode\n", name);
rc = 0;
goto out_unlock;
}
if (atomic_read (&seg->ref_count) != 1) {
pr_warning("DCSS %s is in use and cannot be reloaded\n",
name);
rc = -EAGAIN;
goto out_unlock;
}
release_resource(seg->res);
if (do_nonshared)
seg->res->flags &= ~IORESOURCE_READONLY;
else
if (seg->vm_segtype == SEG_TYPE_SR ||
seg->vm_segtype == SEG_TYPE_ER)
seg->res->flags |= IORESOURCE_READONLY;
if (request_resource(&iomem_resource, seg->res)) {
pr_warning("DCSS %s overlaps with used memory resources "
"and cannot be reloaded\n", name);
rc = -EBUSY;
kfree(seg->res);
goto out_del_mem;
}
dcss_diag(&purgeseg_scode, seg->dcss_name, &dummy, &dummy);
if (do_nonshared)
diag_cc = dcss_diag(&loadnsr_scode, seg->dcss_name,
&start_addr, &end_addr);
else
diag_cc = dcss_diag(&loadshr_scode, seg->dcss_name,
&start_addr, &end_addr);
if (diag_cc < 0) {
rc = diag_cc;
goto out_del_res;
}
if (diag_cc > 1) {
pr_warning("Reloading DCSS %s failed with rc=%ld\n", name,
end_addr);
rc = dcss_diag_translate_rc(end_addr);
goto out_del_res;
}
seg->start_addr = start_addr;
seg->end = end_addr;
seg->do_nonshared = do_nonshared;
rc = 0;
goto out_unlock;
out_del_res:
release_resource(seg->res);
kfree(seg->res);
out_del_mem:
vmem_remove_mapping(seg->start_addr, seg->end - seg->start_addr + 1);
list_del(&seg->list);
dcss_diag(&purgeseg_scode, seg->dcss_name, &dummy, &dummy);
kfree(seg);
out_unlock:
mutex_unlock(&dcss_lock);
return rc;
}
/*
* Decrease the use count of a DCSS segment and remove
* it from the address space if nobody is using it
* any longer.
*/
void
segment_unload(char *name)
{
unsigned long dummy;
struct dcss_segment *seg;
if (!MACHINE_IS_VM)
return;
mutex_lock(&dcss_lock);
seg = segment_by_name (name);
if (seg == NULL) {
pr_err("Unloading unknown DCSS %s failed\n", name);
goto out_unlock;
}
if (atomic_dec_return(&seg->ref_count) != 0)
goto out_unlock;
release_resource(seg->res);
kfree(seg->res);
vmem_remove_mapping(seg->start_addr, seg->end - seg->start_addr + 1);
list_del(&seg->list);
dcss_diag(&purgeseg_scode, seg->dcss_name, &dummy, &dummy);
kfree(seg);
out_unlock:
mutex_unlock(&dcss_lock);
}
/*
* save segment content permanently
*/
void
segment_save(char *name)
{
struct dcss_segment *seg;
char cmd1[160];
char cmd2[80];
int i, response;
if (!MACHINE_IS_VM)
return;
mutex_lock(&dcss_lock);
seg = segment_by_name (name);
if (seg == NULL) {
pr_err("Saving unknown DCSS %s failed\n", name);
goto out;
}
sprintf(cmd1, "DEFSEG %s", name);
for (i=0; i<seg->segcnt; i++) {
sprintf(cmd1+strlen(cmd1), " %lX-%lX %s",
seg->range[i].start >> PAGE_SHIFT,
seg->range[i].end >> PAGE_SHIFT,
segtype_string[seg->range[i].start & 0xff]);
}
sprintf(cmd2, "SAVESEG %s", name);
response = 0;
cpcmd(cmd1, NULL, 0, &response);
if (response) {
pr_err("Saving a DCSS failed with DEFSEG response code "
"%i\n", response);
goto out;
}
cpcmd(cmd2, NULL, 0, &response);
if (response) {
pr_err("Saving a DCSS failed with SAVESEG response code "
"%i\n", response);
goto out;
}
out:
mutex_unlock(&dcss_lock);
}
/*
* print appropriate error message for segment_load()/segment_type()
* return code
*/
void segment_warning(int rc, char *seg_name)
{
switch (rc) {
case -ENOENT:
pr_err("DCSS %s cannot be loaded or queried\n", seg_name);
break;
case -ENOSYS:
pr_err("DCSS %s cannot be loaded or queried without "
"z/VM\n", seg_name);
break;
case -EIO:
pr_err("Loading or querying DCSS %s resulted in a "
"hardware error\n", seg_name);
break;
case -EOPNOTSUPP:
pr_err("DCSS %s has multiple page ranges and cannot be "
"loaded or queried\n", seg_name);
break;
case -ENOSPC:
pr_err("DCSS %s overlaps with used storage and cannot "
"be loaded\n", seg_name);
break;
case -EBUSY:
pr_err("%s needs used memory resources and cannot be "
"loaded or queried\n", seg_name);
break;
case -EPERM:
pr_err("DCSS %s is already loaded in a different access "
"mode\n", seg_name);
break;
case -ENOMEM:
pr_err("There is not enough memory to load or query "
"DCSS %s\n", seg_name);
break;
case -ERANGE:
pr_err("DCSS %s exceeds the kernel mapping range (%lu) "
"and cannot be loaded\n", seg_name, VMEM_MAX_PHYS);
break;
default:
break;
}
}
EXPORT_SYMBOL(segment_load);
EXPORT_SYMBOL(segment_unload);
EXPORT_SYMBOL(segment_save);
EXPORT_SYMBOL(segment_type);
EXPORT_SYMBOL(segment_modify_shared);
EXPORT_SYMBOL(segment_warning);