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s390/cio: rework channel-utilization-block handling

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Convert channel-utilization-block (CUB) address variables from separate
named fields to arrays of addresses. Also simplify error handling and
introduce named constants. This is done in preparation of introducing
additional CUBs.

Note: With this change the __packed annotation of secm_area is required
to prevent an alignment hole that would otherwise occur due to the
switch from u32 to dma64_t.

Reviewed-by: Vineeth Vijayan <vneethv@linux.ibm.com>
Acked-by: Heiko Carstens <hca@linux.ibm.com>
Signed-off-by: Peter Oberparleiter <oberpar@linux.ibm.com>
Signed-off-by: Alexander Gordeev <agordeev@linux.ibm.com>
This commit is contained in:
Peter Oberparleiter 2024-03-26 17:03:20 +01:00 committed by Alexander Gordeev
parent d35c34bb32
commit a817d98dc2
3 changed files with 49 additions and 25 deletions
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8
drivers/s390/cio/chp.c
View File

@ -161,12 +161,12 @@ static void chp_measurement_copy_block(struct cmg_entry *buf,
struct cmg_entry *entry, reference_buf;
int idx;
if (chpid.id < 128) {
area = css->cub_addr1;
if (chpid.id < CSS_CUES_PER_PAGE) {
area = css->cub[0];
idx = chpid.id;
} else {
area = css->cub_addr2;
idx = chpid.id - 128;
area = css->cub[1];
idx = chpid.id - CSS_CUES_PER_PAGE;
}
entry = area + (idx * sizeof(struct cmg_entry));
do {

56
drivers/s390/cio/chsc.c
View File

@ -874,19 +874,16 @@ int __chsc_do_secm(struct channel_subsystem *css, int enable)
u32 : 30;
u32 key : 4;
u32 : 28;
u32 zeroes1;
dma32_t cub_addr1;
u32 zeroes2;
dma32_t cub_addr2;
dma64_t cub[CSS_NUM_CUB_PAGES];
u32 reserved[13];
struct chsc_header response;
u32 status : 8;
u32 : 4;
u32 fmt : 4;
u32 : 16;
} *secm_area;
} __packed *secm_area;
unsigned long flags;
int ret, ccode;
int ret, ccode, i;
spin_lock_irqsave(&chsc_page_lock, flags);
memset(chsc_page, 0, PAGE_SIZE);
@ -895,8 +892,9 @@ int __chsc_do_secm(struct channel_subsystem *css, int enable)
secm_area->request.code = 0x0016;
secm_area->key = PAGE_DEFAULT_KEY >> 4;
secm_area->cub_addr1 = virt_to_dma32(css->cub_addr1);
secm_area->cub_addr2 = virt_to_dma32(css->cub_addr2);
for (i = 0; i < CSS_NUM_CUB_PAGES; i++)
secm_area->cub[i] = (__force dma64_t)virt_to_dma32(css->cub[i]);
secm_area->operation_code = enable ? 0 : 1;
@ -922,19 +920,38 @@ int __chsc_do_secm(struct channel_subsystem *css, int enable)
return ret;
}
static int cub_alloc(struct channel_subsystem *css)
{
int i;
for (i = 0; i < CSS_NUM_CUB_PAGES; i++) {
css->cub[i] = (void *)get_zeroed_page(GFP_KERNEL | GFP_DMA);
if (!css->cub[i])
return -ENOMEM;
}
return 0;
}
static void cub_free(struct channel_subsystem *css)
{
int i;
for (i = 0; i < CSS_NUM_CUB_PAGES; i++) {
free_page((unsigned long)css->cub[i]);
css->cub[i] = NULL;
}
}
int
chsc_secm(struct channel_subsystem *css, int enable)
{
int ret;
if (enable && !css->cm_enabled) {
css->cub_addr1 = (void *)get_zeroed_page(GFP_KERNEL | GFP_DMA);
css->cub_addr2 = (void *)get_zeroed_page(GFP_KERNEL | GFP_DMA);
if (!css->cub_addr1 || !css->cub_addr2) {
free_page((unsigned long)css->cub_addr1);
free_page((unsigned long)css->cub_addr2);
return -ENOMEM;
}
ret = cub_alloc(css);
if (ret)
goto out;
}
ret = __chsc_do_secm(css, enable);
if (!ret) {
@ -948,10 +965,11 @@ chsc_secm(struct channel_subsystem *css, int enable)
} else
chsc_remove_cmg_attr(css);
}
if (!css->cm_enabled) {
free_page((unsigned long)css->cub_addr1);
free_page((unsigned long)css->cub_addr2);
}
out:
if (!css->cm_enabled)
cub_free(css);
return ret;
}

10
drivers/s390/cio/css.h
View File

@ -34,6 +34,13 @@
#define SNID_STATE3_MULTI_PATH 1
#define SNID_STATE3_SINGLE_PATH 0
/*
* Miscellaneous constants
*/
#define CSS_NUM_CUB_PAGES 2
#define CSS_CUES_PER_PAGE 128
/*
* Conditions used to specify which subchannels need evaluation
*/
@ -122,8 +129,7 @@ struct channel_subsystem {
struct mutex mutex;
/* channel measurement related */
int cm_enabled;
void *cub_addr1;
void *cub_addr2;
void *cub[CSS_NUM_CUB_PAGES];
/* for orphaned ccw devices */
struct subchannel *pseudo_subchannel;
};