linux/drivers/misc/sgi-xp/xpc_partition.c
Robin@sgi.com c22c7aeff6 sgi-xpc: XPC fails to discover partitions with all nasids above 128
UV hardware defines 256 memory protection regions versus the baseline 64
with increasing size for the SN2 ia64.  This was overlooked when XPC was
modified to accomodate both UV and SN2.

Without this patch, a user could reconfigure their existing system and
suddenly disable cross-partition communications with no indication of what
has gone wrong.  It also prevents larger configurations from using
cross-partition communication.

Signed-off-by: Robin Holt <holt@sgi.com>
Cc: <stable@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2010-11-25 06:50:40 +09:00

541 lines
14 KiB
C

/*
* This file is subject to the terms and conditions of the GNU General Public
* License. See the file "COPYING" in the main directory of this archive
* for more details.
*
* Copyright (c) 2004-2008 Silicon Graphics, Inc. All Rights Reserved.
*/
/*
* Cross Partition Communication (XPC) partition support.
*
* This is the part of XPC that detects the presence/absence of
* other partitions. It provides a heartbeat and monitors the
* heartbeats of other partitions.
*
*/
#include <linux/device.h>
#include <linux/hardirq.h>
#include <linux/slab.h>
#include "xpc.h"
#include <asm/uv/uv_hub.h>
/* XPC is exiting flag */
int xpc_exiting;
/* this partition's reserved page pointers */
struct xpc_rsvd_page *xpc_rsvd_page;
static unsigned long *xpc_part_nasids;
unsigned long *xpc_mach_nasids;
static int xpc_nasid_mask_nbytes; /* #of bytes in nasid mask */
int xpc_nasid_mask_nlongs; /* #of longs in nasid mask */
struct xpc_partition *xpc_partitions;
/*
* Guarantee that the kmalloc'd memory is cacheline aligned.
*/
void *
xpc_kmalloc_cacheline_aligned(size_t size, gfp_t flags, void **base)
{
/* see if kmalloc will give us cachline aligned memory by default */
*base = kmalloc(size, flags);
if (*base == NULL)
return NULL;
if ((u64)*base == L1_CACHE_ALIGN((u64)*base))
return *base;
kfree(*base);
/* nope, we'll have to do it ourselves */
*base = kmalloc(size + L1_CACHE_BYTES, flags);
if (*base == NULL)
return NULL;
return (void *)L1_CACHE_ALIGN((u64)*base);
}
/*
* Given a nasid, get the physical address of the partition's reserved page
* for that nasid. This function returns 0 on any error.
*/
static unsigned long
xpc_get_rsvd_page_pa(int nasid)
{
enum xp_retval ret;
u64 cookie = 0;
unsigned long rp_pa = nasid; /* seed with nasid */
size_t len = 0;
size_t buf_len = 0;
void *buf = buf;
void *buf_base = NULL;
enum xp_retval (*get_partition_rsvd_page_pa)
(void *, u64 *, unsigned long *, size_t *) =
xpc_arch_ops.get_partition_rsvd_page_pa;
while (1) {
/* !!! rp_pa will need to be _gpa on UV.
* ??? So do we save it into the architecture specific parts
* ??? of the xpc_partition structure? Do we rename this
* ??? function or have two versions? Rename rp_pa for UV to
* ??? rp_gpa?
*/
ret = get_partition_rsvd_page_pa(buf, &cookie, &rp_pa, &len);
dev_dbg(xpc_part, "SAL returned with ret=%d, cookie=0x%016lx, "
"address=0x%016lx, len=0x%016lx\n", ret,
(unsigned long)cookie, rp_pa, len);
if (ret != xpNeedMoreInfo)
break;
/* !!! L1_CACHE_ALIGN() is only a sn2-bte_copy requirement */
if (is_shub())
len = L1_CACHE_ALIGN(len);
if (len > buf_len) {
if (buf_base != NULL)
kfree(buf_base);
buf_len = L1_CACHE_ALIGN(len);
buf = xpc_kmalloc_cacheline_aligned(buf_len, GFP_KERNEL,
&buf_base);
if (buf_base == NULL) {
dev_err(xpc_part, "unable to kmalloc "
"len=0x%016lx\n", buf_len);
ret = xpNoMemory;
break;
}
}
ret = xp_remote_memcpy(xp_pa(buf), rp_pa, len);
if (ret != xpSuccess) {
dev_dbg(xpc_part, "xp_remote_memcpy failed %d\n", ret);
break;
}
}
kfree(buf_base);
if (ret != xpSuccess)
rp_pa = 0;
dev_dbg(xpc_part, "reserved page at phys address 0x%016lx\n", rp_pa);
return rp_pa;
}
/*
* Fill the partition reserved page with the information needed by
* other partitions to discover we are alive and establish initial
* communications.
*/
int
xpc_setup_rsvd_page(void)
{
int ret;
struct xpc_rsvd_page *rp;
unsigned long rp_pa;
unsigned long new_ts_jiffies;
/* get the local reserved page's address */
preempt_disable();
rp_pa = xpc_get_rsvd_page_pa(xp_cpu_to_nasid(smp_processor_id()));
preempt_enable();
if (rp_pa == 0) {
dev_err(xpc_part, "SAL failed to locate the reserved page\n");
return -ESRCH;
}
rp = (struct xpc_rsvd_page *)__va(xp_socket_pa(rp_pa));
if (rp->SAL_version < 3) {
/* SAL_versions < 3 had a SAL_partid defined as a u8 */
rp->SAL_partid &= 0xff;
}
BUG_ON(rp->SAL_partid != xp_partition_id);
if (rp->SAL_partid < 0 || rp->SAL_partid >= xp_max_npartitions) {
dev_err(xpc_part, "the reserved page's partid of %d is outside "
"supported range (< 0 || >= %d)\n", rp->SAL_partid,
xp_max_npartitions);
return -EINVAL;
}
rp->version = XPC_RP_VERSION;
rp->max_npartitions = xp_max_npartitions;
/* establish the actual sizes of the nasid masks */
if (rp->SAL_version == 1) {
/* SAL_version 1 didn't set the nasids_size field */
rp->SAL_nasids_size = 128;
}
xpc_nasid_mask_nbytes = rp->SAL_nasids_size;
xpc_nasid_mask_nlongs = BITS_TO_LONGS(rp->SAL_nasids_size *
BITS_PER_BYTE);
/* setup the pointers to the various items in the reserved page */
xpc_part_nasids = XPC_RP_PART_NASIDS(rp);
xpc_mach_nasids = XPC_RP_MACH_NASIDS(rp);
ret = xpc_arch_ops.setup_rsvd_page(rp);
if (ret != 0)
return ret;
/*
* Set timestamp of when reserved page was setup by XPC.
* This signifies to the remote partition that our reserved
* page is initialized.
*/
new_ts_jiffies = jiffies;
if (new_ts_jiffies == 0 || new_ts_jiffies == rp->ts_jiffies)
new_ts_jiffies++;
rp->ts_jiffies = new_ts_jiffies;
xpc_rsvd_page = rp;
return 0;
}
void
xpc_teardown_rsvd_page(void)
{
/* a zero timestamp indicates our rsvd page is not initialized */
xpc_rsvd_page->ts_jiffies = 0;
}
/*
* Get a copy of a portion of the remote partition's rsvd page.
*
* remote_rp points to a buffer that is cacheline aligned for BTE copies and
* is large enough to contain a copy of their reserved page header and
* part_nasids mask.
*/
enum xp_retval
xpc_get_remote_rp(int nasid, unsigned long *discovered_nasids,
struct xpc_rsvd_page *remote_rp, unsigned long *remote_rp_pa)
{
int l;
enum xp_retval ret;
/* get the reserved page's physical address */
*remote_rp_pa = xpc_get_rsvd_page_pa(nasid);
if (*remote_rp_pa == 0)
return xpNoRsvdPageAddr;
/* pull over the reserved page header and part_nasids mask */
ret = xp_remote_memcpy(xp_pa(remote_rp), *remote_rp_pa,
XPC_RP_HEADER_SIZE + xpc_nasid_mask_nbytes);
if (ret != xpSuccess)
return ret;
if (discovered_nasids != NULL) {
unsigned long *remote_part_nasids =
XPC_RP_PART_NASIDS(remote_rp);
for (l = 0; l < xpc_nasid_mask_nlongs; l++)
discovered_nasids[l] |= remote_part_nasids[l];
}
/* zero timestamp indicates the reserved page has not been setup */
if (remote_rp->ts_jiffies == 0)
return xpRsvdPageNotSet;
if (XPC_VERSION_MAJOR(remote_rp->version) !=
XPC_VERSION_MAJOR(XPC_RP_VERSION)) {
return xpBadVersion;
}
/* check that both remote and local partids are valid for each side */
if (remote_rp->SAL_partid < 0 ||
remote_rp->SAL_partid >= xp_max_npartitions ||
remote_rp->max_npartitions <= xp_partition_id) {
return xpInvalidPartid;
}
if (remote_rp->SAL_partid == xp_partition_id)
return xpLocalPartid;
return xpSuccess;
}
/*
* See if the other side has responded to a partition deactivate request
* from us. Though we requested the remote partition to deactivate with regard
* to us, we really only need to wait for the other side to disengage from us.
*/
int
xpc_partition_disengaged(struct xpc_partition *part)
{
short partid = XPC_PARTID(part);
int disengaged;
disengaged = !xpc_arch_ops.partition_engaged(partid);
if (part->disengage_timeout) {
if (!disengaged) {
if (time_is_after_jiffies(part->disengage_timeout)) {
/* timelimit hasn't been reached yet */
return 0;
}
/*
* Other side hasn't responded to our deactivate
* request in a timely fashion, so assume it's dead.
*/
dev_info(xpc_part, "deactivate request to remote "
"partition %d timed out\n", partid);
xpc_disengage_timedout = 1;
xpc_arch_ops.assume_partition_disengaged(partid);
disengaged = 1;
}
part->disengage_timeout = 0;
/* cancel the timer function, provided it's not us */
if (!in_interrupt())
del_singleshot_timer_sync(&part->disengage_timer);
DBUG_ON(part->act_state != XPC_P_AS_DEACTIVATING &&
part->act_state != XPC_P_AS_INACTIVE);
if (part->act_state != XPC_P_AS_INACTIVE)
xpc_wakeup_channel_mgr(part);
xpc_arch_ops.cancel_partition_deactivation_request(part);
}
return disengaged;
}
/*
* Mark specified partition as active.
*/
enum xp_retval
xpc_mark_partition_active(struct xpc_partition *part)
{
unsigned long irq_flags;
enum xp_retval ret;
dev_dbg(xpc_part, "setting partition %d to ACTIVE\n", XPC_PARTID(part));
spin_lock_irqsave(&part->act_lock, irq_flags);
if (part->act_state == XPC_P_AS_ACTIVATING) {
part->act_state = XPC_P_AS_ACTIVE;
ret = xpSuccess;
} else {
DBUG_ON(part->reason == xpSuccess);
ret = part->reason;
}
spin_unlock_irqrestore(&part->act_lock, irq_flags);
return ret;
}
/*
* Start the process of deactivating the specified partition.
*/
void
xpc_deactivate_partition(const int line, struct xpc_partition *part,
enum xp_retval reason)
{
unsigned long irq_flags;
spin_lock_irqsave(&part->act_lock, irq_flags);
if (part->act_state == XPC_P_AS_INACTIVE) {
XPC_SET_REASON(part, reason, line);
spin_unlock_irqrestore(&part->act_lock, irq_flags);
if (reason == xpReactivating) {
/* we interrupt ourselves to reactivate partition */
xpc_arch_ops.request_partition_reactivation(part);
}
return;
}
if (part->act_state == XPC_P_AS_DEACTIVATING) {
if ((part->reason == xpUnloading && reason != xpUnloading) ||
reason == xpReactivating) {
XPC_SET_REASON(part, reason, line);
}
spin_unlock_irqrestore(&part->act_lock, irq_flags);
return;
}
part->act_state = XPC_P_AS_DEACTIVATING;
XPC_SET_REASON(part, reason, line);
spin_unlock_irqrestore(&part->act_lock, irq_flags);
/* ask remote partition to deactivate with regard to us */
xpc_arch_ops.request_partition_deactivation(part);
/* set a timelimit on the disengage phase of the deactivation request */
part->disengage_timeout = jiffies + (xpc_disengage_timelimit * HZ);
part->disengage_timer.expires = part->disengage_timeout;
add_timer(&part->disengage_timer);
dev_dbg(xpc_part, "bringing partition %d down, reason = %d\n",
XPC_PARTID(part), reason);
xpc_partition_going_down(part, reason);
}
/*
* Mark specified partition as inactive.
*/
void
xpc_mark_partition_inactive(struct xpc_partition *part)
{
unsigned long irq_flags;
dev_dbg(xpc_part, "setting partition %d to INACTIVE\n",
XPC_PARTID(part));
spin_lock_irqsave(&part->act_lock, irq_flags);
part->act_state = XPC_P_AS_INACTIVE;
spin_unlock_irqrestore(&part->act_lock, irq_flags);
part->remote_rp_pa = 0;
}
/*
* SAL has provided a partition and machine mask. The partition mask
* contains a bit for each even nasid in our partition. The machine
* mask contains a bit for each even nasid in the entire machine.
*
* Using those two bit arrays, we can determine which nasids are
* known in the machine. Each should also have a reserved page
* initialized if they are available for partitioning.
*/
void
xpc_discovery(void)
{
void *remote_rp_base;
struct xpc_rsvd_page *remote_rp;
unsigned long remote_rp_pa;
int region;
int region_size;
int max_regions;
int nasid;
struct xpc_rsvd_page *rp;
unsigned long *discovered_nasids;
enum xp_retval ret;
remote_rp = xpc_kmalloc_cacheline_aligned(XPC_RP_HEADER_SIZE +
xpc_nasid_mask_nbytes,
GFP_KERNEL, &remote_rp_base);
if (remote_rp == NULL)
return;
discovered_nasids = kzalloc(sizeof(long) * xpc_nasid_mask_nlongs,
GFP_KERNEL);
if (discovered_nasids == NULL) {
kfree(remote_rp_base);
return;
}
rp = (struct xpc_rsvd_page *)xpc_rsvd_page;
/*
* The term 'region' in this context refers to the minimum number of
* nodes that can comprise an access protection grouping. The access
* protection is in regards to memory, IOI and IPI.
*/
region_size = xp_region_size;
if (is_uv())
max_regions = 256;
else {
max_regions = 64;
switch (region_size) {
case 128:
max_regions *= 2;
case 64:
max_regions *= 2;
case 32:
max_regions *= 2;
region_size = 16;
DBUG_ON(!is_shub2());
}
}
for (region = 0; region < max_regions; region++) {
if (xpc_exiting)
break;
dev_dbg(xpc_part, "searching region %d\n", region);
for (nasid = (region * region_size * 2);
nasid < ((region + 1) * region_size * 2); nasid += 2) {
if (xpc_exiting)
break;
dev_dbg(xpc_part, "checking nasid %d\n", nasid);
if (test_bit(nasid / 2, xpc_part_nasids)) {
dev_dbg(xpc_part, "PROM indicates Nasid %d is "
"part of the local partition; skipping "
"region\n", nasid);
break;
}
if (!(test_bit(nasid / 2, xpc_mach_nasids))) {
dev_dbg(xpc_part, "PROM indicates Nasid %d was "
"not on Numa-Link network at reset\n",
nasid);
continue;
}
if (test_bit(nasid / 2, discovered_nasids)) {
dev_dbg(xpc_part, "Nasid %d is part of a "
"partition which was previously "
"discovered\n", nasid);
continue;
}
/* pull over the rsvd page header & part_nasids mask */
ret = xpc_get_remote_rp(nasid, discovered_nasids,
remote_rp, &remote_rp_pa);
if (ret != xpSuccess) {
dev_dbg(xpc_part, "unable to get reserved page "
"from nasid %d, reason=%d\n", nasid,
ret);
if (ret == xpLocalPartid)
break;
continue;
}
xpc_arch_ops.request_partition_activation(remote_rp,
remote_rp_pa, nasid);
}
}
kfree(discovered_nasids);
kfree(remote_rp_base);
}
/*
* Given a partid, get the nasids owned by that partition from the
* remote partition's reserved page.
*/
enum xp_retval
xpc_initiate_partid_to_nasids(short partid, void *nasid_mask)
{
struct xpc_partition *part;
unsigned long part_nasid_pa;
part = &xpc_partitions[partid];
if (part->remote_rp_pa == 0)
return xpPartitionDown;
memset(nasid_mask, 0, xpc_nasid_mask_nbytes);
part_nasid_pa = (unsigned long)XPC_RP_PART_NASIDS(part->remote_rp_pa);
return xp_remote_memcpy(xp_pa(nasid_mask), part_nasid_pa,
xpc_nasid_mask_nbytes);
}