// SPDX-License-Identifier: GPL-2.0
|
/*
|
* 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/export.h>
|
#include <linux/memblock.h>
|
#include <linux/ctype.h>
|
#include <linux/ioport.h>
|
#include <linux/refcount.h>
|
#include <linux/pgtable.h>
|
#include <asm/diag.h>
|
#include <asm/page.h>
|
#include <asm/ebcdic.h>
|
#include <asm/errno.h>
|
#include <asm/extmem.h>
|
#include <asm/cpcmd.h>
|
#include <asm/setup.h>
|
|
#define DCSS_PURGESEG 0x08
|
#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];
|
};
|
|
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[16];
|
unsigned long start_addr;
|
unsigned long end;
|
refcount_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 = DCSS_LOADSHRX;
|
static int loadnsr_scode = DCSS_LOADNSRX;
|
static int purgeseg_scode = DCSS_PURGESEG;
|
static int segext_scode = DCSS_SEGEXTX;
|
|
/*
|
* 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;
|
|
rx = (unsigned long) parameter;
|
ry = (unsigned long) *func;
|
|
diag_stat_inc(DIAG_STAT_X064);
|
asm volatile(
|
" diag %0,%1,0x64\n"
|
" ipm %2\n"
|
" srl %2,28\n"
|
: "+d" (rx), "+d" (ry), "=d" (rc) : : "cc");
|
*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_warn("Querying a DCSS type failed with rc=%ld\n", vmrc);
|
rc = dcss_diag_translate_rc (vmrc);
|
goto out_free;
|
}
|
|
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
|
* Must return either an error code < 0, or the segment type code >= 0
|
*/
|
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, segtype;
|
|
start_addr = end_addr = 0;
|
segtype = -1;
|
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 (segment_overlaps_others(seg)) {
|
rc = -EBUSY;
|
goto out_free;
|
}
|
|
seg->res = kzalloc(sizeof(struct resource), GFP_KERNEL);
|
if (seg->res == NULL) {
|
rc = -ENOMEM;
|
goto out_free;
|
}
|
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';
|
strlcat(seg->res_name, " (DCSS)", sizeof(seg->res_name));
|
seg->res->name = seg->res_name;
|
segtype = seg->vm_segtype;
|
if (segtype == SEG_TYPE_SC ||
|
((segtype == SEG_TYPE_SR || segtype == SEG_TYPE_ER) && !do_nonshared))
|
seg->res->flags |= IORESOURCE_READONLY;
|
|
/* Check for overlapping resources before adding the mapping. */
|
if (request_resource(&iomem_resource, seg->res)) {
|
rc = -EBUSY;
|
goto out_free_resource;
|
}
|
|
rc = vmem_add_mapping(seg->start_addr, seg->end - seg->start_addr + 1);
|
if (rc)
|
goto out_resource;
|
|
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_mapping;
|
}
|
if (diag_cc > 1) {
|
pr_warn("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_mapping;
|
}
|
seg->start_addr = start_addr;
|
seg->end = end_addr;
|
seg->do_nonshared = do_nonshared;
|
refcount_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 %px to %px 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 %px to %px 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_mapping:
|
vmem_remove_mapping(seg->start_addr, seg->end - seg->start_addr + 1);
|
out_resource:
|
release_resource(seg->res);
|
out_free_resource:
|
kfree(seg->res);
|
out_free:
|
kfree(seg);
|
out:
|
return rc < 0 ? rc : segtype;
|
}
|
|
/*
|
* 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
|
* -EBUSY : segment cannot be used (overlaps with dcss or storage)
|
* -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) {
|
refcount_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 (refcount_read(&seg->ref_count) != 1) {
|
pr_warn("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_warn("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_warn("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 (!refcount_dec_and_test(&seg->ref_count))
|
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 -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);
|
