Commit 7ad6a249 authored by Peter Oberparleiter's avatar Peter Oberparleiter Committed by Martin Schwidefsky
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[S390] cio: fix subchannel channel-path data usage



Ensure that channel-path related subchannel data is only retrieved and
used when it is valid and that it is updated when it may have changed.
Signed-off-by: default avatarPeter Oberparleiter <peter.oberparleiter@de.ibm.com>
Signed-off-by: default avatarMartin Schwidefsky <schwidefsky@de.ibm.com>
parent 83b3370c
......@@ -26,155 +26,84 @@
static void *sei_page;
/* FIXME: this is _always_ called for every subchannel. shouldn't we
* process more than one at a time? */
static int
chsc_get_sch_desc_irq(struct subchannel *sch, void *page)
{
int ccode, j;
struct chsc_ssd_area {
struct chsc_header request;
u16 :10;
u16 ssid:2;
u16 :4;
u16 f_sch; /* first subchannel */
u16 :16;
u16 l_sch; /* last subchannel */
u32 :32;
struct chsc_header response;
u32 :32;
u8 sch_valid : 1;
u8 dev_valid : 1;
u8 st : 3; /* subchannel type */
u8 zeroes : 3;
u8 unit_addr; /* unit address */
u16 devno; /* device number */
u8 path_mask;
u8 fla_valid_mask;
u16 sch; /* subchannel */
u8 chpid[8]; /* chpids 0-7 */
u16 fla[8]; /* full link addresses 0-7 */
} __attribute__ ((packed));
struct {
struct chsc_header request;
u16 reserved1a:10;
u16 ssid:2;
u16 reserved1b:4;
u16 f_sch; /* first subchannel */
u16 reserved2;
u16 l_sch; /* last subchannel */
u32 reserved3;
struct chsc_header response;
u32 reserved4;
u8 sch_valid : 1;
u8 dev_valid : 1;
u8 st : 3; /* subchannel type */
u8 zeroes : 3;
u8 unit_addr; /* unit address */
u16 devno; /* device number */
u8 path_mask;
u8 fla_valid_mask;
u16 sch; /* subchannel */
u8 chpid[8]; /* chpids 0-7 */
u16 fla[8]; /* full link addresses 0-7 */
} __attribute__ ((packed)) *ssd_area;
ssd_area = page;
int chsc_get_ssd_info(struct subchannel_id schid, struct chsc_ssd_info *ssd)
{
unsigned long page;
struct chsc_ssd_area *ssd_area;
int ccode;
int ret;
int i;
int mask;
page = get_zeroed_page(GFP_KERNEL | GFP_DMA);
if (!page)
return -ENOMEM;
ssd_area = (struct chsc_ssd_area *) page;
ssd_area->request.length = 0x0010;
ssd_area->request.code = 0x0004;
ssd_area->ssid = sch->schid.ssid;
ssd_area->f_sch = sch->schid.sch_no;
ssd_area->l_sch = sch->schid.sch_no;
ssd_area->ssid = schid.ssid;
ssd_area->f_sch = schid.sch_no;
ssd_area->l_sch = schid.sch_no;
ccode = chsc(ssd_area);
/* Check response. */
if (ccode > 0) {
pr_debug("chsc returned with ccode = %d\n", ccode);
return (ccode == 3) ? -ENODEV : -EBUSY;
ret = (ccode == 3) ? -ENODEV : -EBUSY;
goto out_free;
}
switch (ssd_area->response.code) {
case 0x0001: /* everything ok */
break;
case 0x0002:
CIO_CRW_EVENT(2, "Invalid command!\n");
return -EINVAL;
case 0x0003:
CIO_CRW_EVENT(2, "Error in chsc request block!\n");
return -EINVAL;
case 0x0004:
CIO_CRW_EVENT(2, "Model does not provide ssd\n");
return -EOPNOTSUPP;
default:
CIO_CRW_EVENT(2, "Unknown CHSC response %d\n",
if (ssd_area->response.code != 0x0001) {
CIO_MSG_EVENT(2, "chsc: ssd failed for 0.%x.%04x (rc=%04x)\n",
schid.ssid, schid.sch_no,
ssd_area->response.code);
return -EIO;
}
/*
* ssd_area->st stores the type of the detected
* subchannel, with the following definitions:
*
* 0: I/O subchannel: All fields have meaning
* 1: CHSC subchannel: Only sch_val, st and sch
* have meaning
* 2: Message subchannel: All fields except unit_addr
* have meaning
* 3: ADM subchannel: Only sch_val, st and sch
* have meaning
*
* Other types are currently undefined.
*/
if (ssd_area->st > 3) { /* uhm, that looks strange... */
CIO_CRW_EVENT(0, "Strange subchannel type %d"
" for sch 0.%x.%04x\n", ssd_area->st,
sch->schid.ssid, sch->schid.sch_no);
/*
* There may have been a new subchannel type defined in the
* time since this code was written; since we don't know which
* fields have meaning and what to do with it we just jump out
*/
return 0;
} else {
const char *type[4] = {"I/O", "chsc", "message", "ADM"};
CIO_CRW_EVENT(6, "ssd: sch 0.%x.%04x is %s subchannel\n",
sch->schid.ssid, sch->schid.sch_no,
type[ssd_area->st]);
sch->ssd_info.valid = 1;
sch->ssd_info.type = ssd_area->st;
ret = -EIO;
goto out_free;
}
if (ssd_area->st == 0 || ssd_area->st == 2) {
for (j = 0; j < 8; j++) {
if (!((0x80 >> j) & ssd_area->path_mask &
ssd_area->fla_valid_mask))
continue;
sch->ssd_info.chpid[j] = ssd_area->chpid[j];
sch->ssd_info.fla[j] = ssd_area->fla[j];
}
if (!ssd_area->sch_valid) {
ret = -ENODEV;
goto out_free;
}
return 0;
}
int
css_get_ssd_info(struct subchannel *sch)
{
int ret;
void *page;
page = (void *)get_zeroed_page(GFP_KERNEL | GFP_DMA);
if (!page)
return -ENOMEM;
spin_lock_irq(sch->lock);
ret = chsc_get_sch_desc_irq(sch, page);
if (ret) {
static int cio_chsc_err_msg;
if (!cio_chsc_err_msg) {
printk(KERN_ERR
"chsc_get_sch_descriptions:"
" Error %d while doing chsc; "
"processing some machine checks may "
"not work\n", ret);
cio_chsc_err_msg = 1;
}
}
spin_unlock_irq(sch->lock);
free_page((unsigned long)page);
if (!ret) {
int j, mask;
struct chp_id chpid;
chp_id_init(&chpid);
/* Allocate channel path structures, if needed. */
for (j = 0; j < 8; j++) {
mask = 0x80 >> j;
chpid.id = sch->ssd_info.chpid[j];
if ((sch->schib.pmcw.pim & mask) &&
!chp_is_registered(chpid))
chp_new(chpid);
/* Copy data */
ret = 0;
memset(ssd, 0, sizeof(struct chsc_ssd_info));
if ((ssd_area->st != 0) && (ssd_area->st != 2))
goto out_free;
ssd->path_mask = ssd_area->path_mask;
ssd->fla_valid_mask = ssd_area->fla_valid_mask;
for (i = 0; i < 8; i++) {
mask = 0x80 >> i;
if (ssd_area->path_mask & mask) {
chp_id_init(&ssd->chpid[i]);
ssd->chpid[i].id = ssd_area->chpid[i];
}
if (ssd_area->fla_valid_mask & mask)
ssd->fla[i] = ssd_area->fla[i];
}
out_free:
free_page(page);
return ret;
}
......@@ -276,47 +205,6 @@ void chsc_chp_offline(struct chp_id chpid)
s390_subchannel_remove_chpid);
}
struct res_acc_data {
struct chp_id chpid;
u32 fla_mask;
u16 fla;
};
static int s390_process_res_acc_sch(struct res_acc_data *res_data,
struct subchannel *sch)
{
int found;
int chp;
int ccode;
found = 0;
for (chp = 0; chp <= 7; chp++)
/*
* check if chpid is in information updated by ssd
*/
if (sch->ssd_info.valid &&
sch->ssd_info.chpid[chp] == res_data->chpid.id &&
(sch->ssd_info.fla[chp] & res_data->fla_mask)
== res_data->fla) {
found = 1;
break;
}
if (found == 0)
return 0;
/*
* Do a stsch to update our subchannel structure with the
* new path information and eventually check for logically
* offline chpids.
*/
ccode = stsch(sch->schid, &sch->schib);
if (ccode > 0)
return 0;
return 0x80 >> chp;
}
static int
s390_process_res_acc_new_sch(struct subchannel_id schid)
{
......@@ -338,6 +226,32 @@ s390_process_res_acc_new_sch(struct subchannel_id schid)
return 0;
}
struct res_acc_data {
struct chp_id chpid;
u32 fla_mask;
u16 fla;
};
static int get_res_chpid_mask(struct chsc_ssd_info *ssd,
struct res_acc_data *data)
{
int i;
int mask;
for (i = 0; i < 8; i++) {
mask = 0x80 >> i;
if (!(ssd->path_mask & mask))
continue;
if (!chp_id_is_equal(&ssd->chpid[i], &data->chpid))
continue;
if ((ssd->fla_valid_mask & mask) &&
((ssd->fla[i] & data->fla_mask) != data->fla))
continue;
return mask;
}
return 0;
}
static int
__s390_process_res_acc(struct subchannel_id schid, void *data)
{
......@@ -352,14 +266,11 @@ __s390_process_res_acc(struct subchannel_id schid, void *data)
return s390_process_res_acc_new_sch(schid);
spin_lock_irq(sch->lock);
chp_mask = s390_process_res_acc_sch(res_data, sch);
if (chp_mask == 0) {
spin_unlock_irq(sch->lock);
put_device(&sch->dev);
return 0;
}
chp_mask = get_res_chpid_mask(&sch->ssd_info, res_data);
if (chp_mask == 0)
goto out;
if (stsch(sch->schid, &sch->schib))
goto out;
old_lpm = sch->lpm;
sch->lpm = ((sch->schib.pmcw.pim &
sch->schib.pmcw.pam &
......@@ -369,13 +280,12 @@ __s390_process_res_acc(struct subchannel_id schid, void *data)
device_trigger_reprobe(sch);
else if (sch->driver && sch->driver->verify)
sch->driver->verify(&sch->dev);
out:
spin_unlock_irq(sch->lock);
put_device(&sch->dev);
return 0;
}
static void s390_process_res_acc (struct res_acc_data *res_data)
{
char dbf_txt[15];
......@@ -661,29 +571,30 @@ static void __s390_subchannel_vary_chpid(struct subchannel *sch,
struct chp_id chpid, int on)
{
int chp, old_lpm;
int mask;
unsigned long flags;
if (!sch->ssd_info.valid)
return;
spin_lock_irqsave(sch->lock, flags);
old_lpm = sch->lpm;
for (chp = 0; chp < 8; chp++) {
if (sch->ssd_info.chpid[chp] != chpid.id)
mask = 0x80 >> chp;
if (!(sch->ssd_info.path_mask & mask))
continue;
if (!chp_id_is_equal(&sch->ssd_info.chpid[chp], &chpid))
continue;
if (on) {
sch->opm |= (0x80 >> chp);
sch->lpm |= (0x80 >> chp);
sch->opm |= mask;
sch->lpm |= mask;
if (!old_lpm)
device_trigger_reprobe(sch);
else if (sch->driver && sch->driver->verify)
sch->driver->verify(&sch->dev);
break;
}
sch->opm &= ~(0x80 >> chp);
sch->lpm &= ~(0x80 >> chp);
if (check_for_io_on_path(sch, (0x80 >> chp))) {
sch->opm &= ~mask;
sch->lpm &= ~mask;
if (check_for_io_on_path(sch, mask)) {
if (device_is_online(sch))
/* Path verification is done after killing. */
device_kill_io(sch);
......
......@@ -4,6 +4,7 @@
#include <linux/types.h>
#include <linux/device.h>
#include <asm/chpid.h>
#include "schid.h"
#define CHSC_SDA_OC_MSS 0x2
......@@ -35,7 +36,6 @@ struct channel_path_desc {
struct channel_path;
extern int css_get_ssd_info(struct subchannel *);
extern void chsc_process_crw(void);
struct css_general_char {
......@@ -69,6 +69,14 @@ struct css_chsc_char {
extern struct css_general_char css_general_characteristics;
extern struct css_chsc_char css_chsc_characteristics;
struct chsc_ssd_info {
u8 path_mask;
u8 fla_valid_mask;
struct chp_id chpid[8];
u16 fla[8];
};
extern int chsc_get_ssd_info(struct subchannel_id schid,
struct chsc_ssd_info *ssd);
extern int chsc_determine_css_characteristics(void);
extern int css_characteristics_avail;
......
#ifndef S390_CIO_H
#define S390_CIO_H
#include "schid.h"
#include <linux/mutex.h>
#include <linux/device.h>
/*
* where we put the ssd info
*/
struct ssd_info {
__u8 valid:1;
__u8 type:7; /* subchannel type */
__u8 chpid[8]; /* chpids */
__u16 fla[8]; /* full link addresses */
} __attribute__ ((packed));
#include <asm/chpid.h>
#include "chsc.h"
#include "schid.h"
/*
* path management control word
......@@ -109,7 +101,7 @@ struct subchannel {
struct schib schib; /* subchannel information block */
struct orb orb; /* operation request block */
struct ccw1 sense_ccw; /* static ccw for sense command */
struct ssd_info ssd_info; /* subchannel description */
struct chsc_ssd_info ssd_info; /* subchannel description */
struct device dev; /* entry in device tree */
struct css_driver *driver;
} __attribute__ ((aligned(8)));
......
......@@ -21,6 +21,7 @@
#include "chsc.h"
#include "device.h"
#include "idset.h"
#include "chp.h"
int css_init_done = 0;
static int need_reprobe = 0;
......@@ -125,8 +126,52 @@ void css_sch_device_unregister(struct subchannel *sch)
mutex_unlock(&sch->reg_mutex);
}
static int
css_register_subchannel(struct subchannel *sch)
static void ssd_from_pmcw(struct chsc_ssd_info *ssd, struct pmcw *pmcw)
{
int i;
int mask;
memset(ssd, 0, sizeof(struct chsc_ssd_info));
ssd->path_mask = pmcw->pim;
for (i = 0; i < 8; i++) {
mask = 0x80 >> i;
if (pmcw->pim & mask) {
chp_id_init(&ssd->chpid[i]);
ssd->chpid[i].id = pmcw->chpid[i];
}
}
}
static void ssd_register_chpids(struct chsc_ssd_info *ssd)
{
int i;
int mask;
for (i = 0; i < 8; i++) {
mask = 0x80 >> i;
if (ssd->path_mask & mask)
if (!chp_is_registered(ssd->chpid[i]))
chp_new(ssd->chpid[i]);
}
}
void css_update_ssd_info(struct subchannel *sch)
{
int ret;
if (cio_is_console(sch->schid)) {
/* Console is initialized too early for functions requiring
* memory allocation. */
ssd_from_pmcw(&sch->ssd_info, &sch->schib.pmcw);
} else {
ret = chsc_get_ssd_info(sch->schid, &sch->ssd_info);
if (ret)
ssd_from_pmcw(&sch->ssd_info, &sch->schib.pmcw);
ssd_register_chpids(&sch->ssd_info);
}
}
static int css_register_subchannel(struct subchannel *sch)
{
int ret;
......@@ -135,9 +180,7 @@ css_register_subchannel(struct subchannel *sch)
sch->dev.bus = &css_bus_type;
sch->dev.release = &css_subchannel_release;
sch->dev.groups = subch_attr_groups;
css_get_ssd_info(sch);
css_update_ssd_info(sch);
/* make it known to the system */
ret = css_sch_device_register(sch);
if (ret) {
......
......@@ -148,6 +148,7 @@ extern int css_init_done;
extern int for_each_subchannel(int(*fn)(struct subchannel_id, void *), void *);
extern void css_process_crw(int, int);
extern void css_reiterate_subchannels(void);
void css_update_ssd_info(struct subchannel *sch);
#define __MAX_SUBCHANNEL 65535
#define __MAX_SSID 3
......
......@@ -216,12 +216,18 @@ static ssize_t
chpids_show (struct device * dev, struct device_attribute *attr, char * buf)
{
struct subchannel *sch = to_subchannel(dev);
struct ssd_info *ssd = &sch->ssd_info;
struct chsc_ssd_info *ssd = &sch->ssd_info;
ssize_t ret = 0;
int chp;
int mask;
for (chp = 0; chp < 8; chp++)
ret += sprintf (buf+ret, "%02x ", ssd->chpid[chp]);
for (chp = 0; chp < 8; chp++) {
mask = 0x80 >> chp;
if (ssd->path_mask & mask)
ret += sprintf(buf + ret, "%02x ", ssd->chpid[chp].id);
else
ret += sprintf(buf + ret, "00 ");
}
ret += sprintf (buf+ret, "\n");
return min((ssize_t)PAGE_SIZE, ret);
}
......
......@@ -246,6 +246,7 @@ ccw_device_recog_done(struct ccw_device *cdev, int state)
*/
old_lpm = sch->lpm;
stsch(sch->schid, &sch->schib);
css_update_ssd_info(sch);
sch->lpm = sch->schib.pmcw.pam & sch->opm;
/* Check since device may again have become not operational. */
if (!sch->schib.pmcw.dnv)
......
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