diff options
Diffstat (limited to 'drivers/misc/sgi-xp/xpc_partition.c')
| -rw-r--r-- | drivers/misc/sgi-xp/xpc_partition.c | 1239 |
1 files changed, 1239 insertions, 0 deletions
diff --git a/drivers/misc/sgi-xp/xpc_partition.c b/drivers/misc/sgi-xp/xpc_partition.c new file mode 100644 index 00000000000..7412dc7351c --- /dev/null +++ b/drivers/misc/sgi-xp/xpc_partition.c @@ -0,0 +1,1239 @@ +/* + * 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/kernel.h> +#include <linux/sysctl.h> +#include <linux/cache.h> +#include <linux/mmzone.h> +#include <linux/nodemask.h> +#include <asm/uncached.h> +#include <asm/sn/bte.h> +#include <asm/sn/intr.h> +#include <asm/sn/sn_sal.h> +#include <asm/sn/nodepda.h> +#include <asm/sn/addrs.h> +#include "xpc.h" + + +/* XPC is exiting flag */ +int xpc_exiting; + + +/* SH_IPI_ACCESS shub register value on startup */ +static u64 xpc_sh1_IPI_access; +static u64 xpc_sh2_IPI_access0; +static u64 xpc_sh2_IPI_access1; +static u64 xpc_sh2_IPI_access2; +static u64 xpc_sh2_IPI_access3; + + +/* original protection values for each node */ +u64 xpc_prot_vec[MAX_NUMNODES]; + + +/* this partition's reserved page pointers */ +struct xpc_rsvd_page *xpc_rsvd_page; +static u64 *xpc_part_nasids; +static u64 *xpc_mach_nasids; +struct xpc_vars *xpc_vars; +struct xpc_vars_part *xpc_vars_part; + +static int xp_nasid_mask_bytes; /* actual size in bytes of nasid mask */ +static int xp_nasid_mask_words; /* actual size in words of nasid mask */ + + +/* + * For performance reasons, each entry of xpc_partitions[] is cacheline + * aligned. And xpc_partitions[] is padded with an additional entry at the + * end so that the last legitimate entry doesn't share its cacheline with + * another variable. + */ +struct xpc_partition xpc_partitions[XP_MAX_PARTITIONS + 1]; + + +/* + * Generic buffer used to store a local copy of portions of a remote + * partition's reserved page (either its header and part_nasids mask, + * or its vars). + */ +char *xpc_remote_copy_buffer; +void *xpc_remote_copy_buffer_base; + + +/* + * 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 u64 +xpc_get_rsvd_page_pa(int nasid) +{ + bte_result_t bte_res; + s64 status; + u64 cookie = 0; + u64 rp_pa = nasid; /* seed with nasid */ + u64 len = 0; + u64 buf = buf; + u64 buf_len = 0; + void *buf_base = NULL; + + + while (1) { + + status = sn_partition_reserved_page_pa(buf, &cookie, &rp_pa, + &len); + + dev_dbg(xpc_part, "SAL returned with status=%li, cookie=" + "0x%016lx, address=0x%016lx, len=0x%016lx\n", + status, cookie, rp_pa, len); + + if (status != SALRET_MORE_PASSES) { + break; + } + + if (L1_CACHE_ALIGN(len) > buf_len) { + kfree(buf_base); + buf_len = L1_CACHE_ALIGN(len); + buf = (u64) 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); + status = SALRET_ERROR; + break; + } + } + + bte_res = xp_bte_copy(rp_pa, buf, buf_len, + (BTE_NOTIFY | BTE_WACQUIRE), NULL); + if (bte_res != BTE_SUCCESS) { + dev_dbg(xpc_part, "xp_bte_copy failed %i\n", bte_res); + status = SALRET_ERROR; + break; + } + } + + kfree(buf_base); + + if (status != SALRET_OK) { + 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. + */ +struct xpc_rsvd_page * +xpc_rsvd_page_init(void) +{ + struct xpc_rsvd_page *rp; + AMO_t *amos_page; + u64 rp_pa, nasid_array = 0; + int i, ret; + + + /* get the local reserved page's address */ + + preempt_disable(); + rp_pa = xpc_get_rsvd_page_pa(cpuid_to_nasid(smp_processor_id())); + preempt_enable(); + if (rp_pa == 0) { + dev_err(xpc_part, "SAL failed to locate the reserved page\n"); + return NULL; + } + rp = (struct xpc_rsvd_page *) __va(rp_pa); + + if (rp->partid != sn_partition_id) { + dev_err(xpc_part, "the reserved page's partid of %d should be " + "%d\n", rp->partid, sn_partition_id); + return NULL; + } + + rp->version = XPC_RP_VERSION; + + /* establish the actual sizes of the nasid masks */ + if (rp->SAL_version == 1) { + /* SAL_version 1 didn't set the nasids_size field */ + rp->nasids_size = 128; + } + xp_nasid_mask_bytes = rp->nasids_size; + xp_nasid_mask_words = xp_nasid_mask_bytes / 8; + + /* 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); + xpc_vars = XPC_RP_VARS(rp); + xpc_vars_part = XPC_RP_VARS_PART(rp); + + /* + * Before clearing xpc_vars, see if a page of AMOs had been previously + * allocated. If not we'll need to allocate one and set permissions + * so that cross-partition AMOs are allowed. + * + * The allocated AMO page needs MCA reporting to remain disabled after + * XPC has unloaded. To make this work, we keep a copy of the pointer + * to this page (i.e., amos_page) in the struct xpc_vars structure, + * which is pointed to by the reserved page, and re-use that saved copy + * on subsequent loads of XPC. This AMO page is never freed, and its + * memory protections are never restricted. + */ + if ((amos_page = xpc_vars->amos_page) == NULL) { + amos_page = (AMO_t *) TO_AMO(uncached_alloc_page(0)); + if (amos_page == NULL) { + dev_err(xpc_part, "can't allocate page of AMOs\n"); + return NULL; + } + + /* + * Open up AMO-R/W to cpu. This is done for Shub 1.1 systems + * when xpc_allow_IPI_ops() is called via xpc_hb_init(). + */ + if (!enable_shub_wars_1_1()) { + ret = sn_change_memprotect(ia64_tpa((u64) amos_page), + PAGE_SIZE, SN_MEMPROT_ACCESS_CLASS_1, + &nasid_array); + if (ret != 0) { + dev_err(xpc_part, "can't change memory " + "protections\n"); + uncached_free_page(__IA64_UNCACHED_OFFSET | + TO_PHYS((u64) amos_page)); + return NULL; + } + } + } else if (!IS_AMO_ADDRESS((u64) amos_page)) { + /* + * EFI's XPBOOT can also set amos_page in the reserved page, + * but it happens to leave it as an uncached physical address + * and we need it to be an uncached virtual, so we'll have to + * convert it. + */ + if (!IS_AMO_PHYS_ADDRESS((u64) amos_page)) { + dev_err(xpc_part, "previously used amos_page address " + "is bad = 0x%p\n", (void *) amos_page); + return NULL; + } + amos_page = (AMO_t *) TO_AMO((u64) amos_page); + } + + /* clear xpc_vars */ + memset(xpc_vars, 0, sizeof(struct xpc_vars)); + + xpc_vars->version = XPC_V_VERSION; + xpc_vars->act_nasid = cpuid_to_nasid(0); + xpc_vars->act_phys_cpuid = cpu_physical_id(0); + xpc_vars->vars_part_pa = __pa(xpc_vars_part); + xpc_vars->amos_page_pa = ia64_tpa((u64) amos_page); + xpc_vars->amos_page = amos_page; /* save for next load of XPC */ + + + /* clear xpc_vars_part */ + memset((u64 *) xpc_vars_part, 0, sizeof(struct xpc_vars_part) * + XP_MAX_PARTITIONS); + + /* initialize the activate IRQ related AMO variables */ + for (i = 0; i < xp_nasid_mask_words; i++) { + (void) xpc_IPI_init(XPC_ACTIVATE_IRQ_AMOS + i); + } + + /* initialize the engaged remote partitions related AMO variables */ + (void) xpc_IPI_init(XPC_ENGAGED_PARTITIONS_AMO); + (void) xpc_IPI_init(XPC_DISENGAGE_REQUEST_AMO); + + /* timestamp of when reserved page was setup by XPC */ + rp->stamp = CURRENT_TIME; + + /* + * This signifies to the remote partition that our reserved + * page is initialized. + */ + rp->vars_pa = __pa(xpc_vars); + + return rp; +} + + +/* + * Change protections to allow IPI operations (and AMO operations on + * Shub 1.1 systems). + */ +void +xpc_allow_IPI_ops(void) +{ + int node; + int nasid; + + + // >>> Change SH_IPI_ACCESS code to use SAL call once it is available. + + if (is_shub2()) { + xpc_sh2_IPI_access0 = + (u64) HUB_L((u64 *) LOCAL_MMR_ADDR(SH2_IPI_ACCESS0)); + xpc_sh2_IPI_access1 = + (u64) HUB_L((u64 *) LOCAL_MMR_ADDR(SH2_IPI_ACCESS1)); + xpc_sh2_IPI_access2 = + (u64) HUB_L((u64 *) LOCAL_MMR_ADDR(SH2_IPI_ACCESS2)); + xpc_sh2_IPI_access3 = + (u64) HUB_L((u64 *) LOCAL_MMR_ADDR(SH2_IPI_ACCESS3)); + + for_each_online_node(node) { + nasid = cnodeid_to_nasid(node); + HUB_S((u64 *) GLOBAL_MMR_ADDR(nasid, SH2_IPI_ACCESS0), + -1UL); + HUB_S((u64 *) GLOBAL_MMR_ADDR(nasid, SH2_IPI_ACCESS1), + -1UL); + HUB_S((u64 *) GLOBAL_MMR_ADDR(nasid, SH2_IPI_ACCESS2), + -1UL); + HUB_S((u64 *) GLOBAL_MMR_ADDR(nasid, SH2_IPI_ACCESS3), + -1UL); + } + + } else { + xpc_sh1_IPI_access = + (u64) HUB_L((u64 *) LOCAL_MMR_ADDR(SH1_IPI_ACCESS)); + + for_each_online_node(node) { + nasid = cnodeid_to_nasid(node); + HUB_S((u64 *) GLOBAL_MMR_ADDR(nasid, SH1_IPI_ACCESS), + -1UL); + + /* + * Since the BIST collides with memory operations on + * SHUB 1.1 sn_change_memprotect() cannot be used. + */ + if (enable_shub_wars_1_1()) { + /* open up everything */ + xpc_prot_vec[node] = (u64) HUB_L((u64 *) + GLOBAL_MMR_ADDR(nasid, + SH1_MD_DQLP_MMR_DIR_PRIVEC0)); + HUB_S((u64 *) GLOBAL_MMR_ADDR(nasid, + SH1_MD_DQLP_MMR_DIR_PRIVEC0), + -1UL); + HUB_S((u64 *) GLOBAL_MMR_ADDR(nasid, + SH1_MD_DQRP_MMR_DIR_PRIVEC0), + -1UL); + } + } + } +} + + +/* + * Restrict protections to disallow IPI operations (and AMO operations on + * Shub 1.1 systems). + */ +void +xpc_restrict_IPI_ops(void) +{ + int node; + int nasid; + + + // >>> Change SH_IPI_ACCESS code to use SAL call once it is available. + + if (is_shub2()) { + + for_each_online_node(node) { + nasid = cnodeid_to_nasid(node); + HUB_S((u64 *) GLOBAL_MMR_ADDR(nasid, SH2_IPI_ACCESS0), + xpc_sh2_IPI_access0); + HUB_S((u64 *) GLOBAL_MMR_ADDR(nasid, SH2_IPI_ACCESS1), + xpc_sh2_IPI_access1); + HUB_S((u64 *) GLOBAL_MMR_ADDR(nasid, SH2_IPI_ACCESS2), + xpc_sh2_IPI_access2); + HUB_S((u64 *) GLOBAL_MMR_ADDR(nasid, SH2_IPI_ACCESS3), + xpc_sh2_IPI_access3); + } + + } else { + + for_each_online_node(node) { + nasid = cnodeid_to_nasid(node); + HUB_S((u64 *) GLOBAL_MMR_ADDR(nasid, SH1_IPI_ACCESS), + xpc_sh1_IPI_access); + + if (enable_shub_wars_1_1()) { + HUB_S((u64 *) GLOBAL_MMR_ADDR(nasid, + SH1_MD_DQLP_MMR_DIR_PRIVEC0), + xpc_prot_vec[node]); + HUB_S((u64 *) GLOBAL_MMR_ADDR(nasid, + SH1_MD_DQRP_MMR_DIR_PRIVEC0), + xpc_prot_vec[node]); + } + } + } +} + + +/* + * At periodic intervals, scan through all active partitions and ensure + * their heartbeat is still active. If not, the partition is deactivated. + */ +void +xpc_check_remote_hb(void) +{ + struct xpc_vars *remote_vars; + struct xpc_partition *part; + partid_t partid; + bte_result_t bres; + + + remote_vars = (struct xpc_vars *) xpc_remote_copy_buffer; + + for (partid = 1; partid < XP_MAX_PARTITIONS; partid++) { + + if (xpc_exiting) { + break; + } + + if (partid == sn_partition_id) { + continue; + } + + part = &xpc_partitions[partid]; + + if (part->act_state == XPC_P_INACTIVE || + part->act_state == XPC_P_DEACTIVATING) { + continue; + } + + /* pull the remote_hb cache line */ + bres = xp_bte_copy(part->remote_vars_pa, + (u64) remote_vars, + XPC_RP_VARS_SIZE, + (BTE_NOTIFY | BTE_WACQUIRE), NULL); + if (bres != BTE_SUCCESS) { + XPC_DEACTIVATE_PARTITION(part, + xpc_map_bte_errors(bres)); + continue; + } + + dev_dbg(xpc_part, "partid = %d, heartbeat = %ld, last_heartbeat" + " = %ld, heartbeat_offline = %ld, HB_mask = 0x%lx\n", + partid, remote_vars->heartbeat, part->last_heartbeat, + remote_vars->heartbeat_offline, + remote_vars->heartbeating_to_mask); + + if (((remote_vars->heartbeat == part->last_heartbeat) && + (remote_vars->heartbeat_offline == 0)) || + !xpc_hb_allowed(sn_partition_id, remote_vars)) { + + XPC_DEACTIVATE_PARTITION(part, xpcNoHeartbeat); + continue; + } + + part->last_heartbeat = remote_vars->heartbeat; + } +} + + +/* + * 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. + */ +static enum xpc_retval +xpc_get_remote_rp(int nasid, u64 *discovered_nasids, + struct xpc_rsvd_page *remote_rp, u64 *remote_rp_pa) +{ + int bres, i; + + + /* get the reserved page's physical address */ + + *remote_rp_pa = xpc_get_rsvd_page_pa(nasid); + if (*remote_rp_pa == 0) { + return xpcNoRsvdPageAddr; + } + + + /* pull over the reserved page header and part_nasids mask */ + bres = xp_bte_copy(*remote_rp_pa, (u64) remote_rp, + XPC_RP_HEADER_SIZE + xp_nasid_mask_bytes, + (BTE_NOTIFY | BTE_WACQUIRE), NULL); + if (bres != BTE_SUCCESS) { + return xpc_map_bte_errors(bres); + } + + + if (discovered_nasids != NULL) { + u64 *remote_part_nasids = XPC_RP_PART_NASIDS(remote_rp); + + + for (i = 0; i < xp_nasid_mask_words; i++) { + discovered_nasids[i] |= remote_part_nasids[i]; + } + } + + + /* check that the partid is for another partition */ + + if (remote_rp->partid < 1 || + remote_rp->partid > (XP_MAX_PARTITIONS - 1)) { + return xpcInvalidPartid; + } + + if (remote_rp->partid == sn_partition_id) { + return xpcLocalPartid; + } + + + if (XPC_VERSION_MAJOR(remote_rp->version) != + XPC_VERSION_MAJOR(XPC_RP_VERSION)) { + return xpcBadVersion; + } + + return xpcSuccess; +} + + +/* + * Get a copy of the remote partition's XPC variables from the reserved page. + * + * remote_vars points to a buffer that is cacheline aligned for BTE copies and + * assumed to be of size XPC_RP_VARS_SIZE. + */ +static enum xpc_retval +xpc_get_remote_vars(u64 remote_vars_pa, struct xpc_vars *remote_vars) +{ + int bres; + + + if (remote_vars_pa == 0) { + return xpcVarsNotSet; + } + + /* pull over the cross partition variables */ + bres = xp_bte_copy(remote_vars_pa, (u64) remote_vars, XPC_RP_VARS_SIZE, + (BTE_NOTIFY | BTE_WACQUIRE), NULL); + if (bres != BTE_SUCCESS) { + return xpc_map_bte_errors(bres); + } + + if (XPC_VERSION_MAJOR(remote_vars->version) != + XPC_VERSION_MAJOR(XPC_V_VERSION)) { + return xpcBadVersion; + } + + return xpcSuccess; +} + + +/* + * Update the remote partition's info. + */ +static void +xpc_update_partition_info(struct xpc_partition *part, u8 remote_rp_version, + struct timespec *remote_rp_stamp, u64 remote_rp_pa, + u64 remote_vars_pa, struct xpc_vars *remote_vars) +{ + part->remote_rp_version = remote_rp_version; + dev_dbg(xpc_part, " remote_rp_version = 0x%016x\n", + part->remote_rp_version); + + part->remote_rp_stamp = *remote_rp_stamp; + dev_dbg(xpc_part, " remote_rp_stamp (tv_sec = 0x%lx tv_nsec = 0x%lx\n", + part->remote_rp_stamp.tv_sec, part->remote_rp_stamp.tv_nsec); + + part->remote_rp_pa = remote_rp_pa; + dev_dbg(xpc_part, " remote_rp_pa = 0x%016lx\n", part->remote_rp_pa); + + part->remote_vars_pa = remote_vars_pa; + dev_dbg(xpc_part, " remote_vars_pa = 0x%016lx\n", + part->remote_vars_pa); + + part->last_heartbeat = remote_vars->heartbeat; + dev_dbg(xpc_part, " last_heartbeat = 0x%016lx\n", + part->last_heartbeat); + + part->remote_vars_part_pa = remote_vars->vars_part_pa; + dev_dbg(xpc_part, " remote_vars_part_pa = 0x%016lx\n", + part->remote_vars_part_pa); + + part->remote_act_nasid = remote_vars->act_nasid; + dev_dbg(xpc_part, " remote_act_nasid = 0x%x\n", + part->remote_act_nasid); + + part->remote_act_phys_cpuid = remote_vars->act_phys_cpuid; + dev_dbg(xpc_part, " remote_act_phys_cpuid = 0x%x\n", + part->remote_act_phys_cpuid); + + part->remote_amos_page_pa = remote_vars->amos_page_pa; + dev_dbg(xpc_part, " remote_amos_page_pa = 0x%lx\n", + part->remote_amos_page_pa); + + part->remote_vars_version = remote_vars->version; + dev_dbg(xpc_part, " remote_vars_version = 0x%x\n", + part->remote_vars_version); +} + + +/* + * Prior code has determined the nasid which generated an IPI. Inspect + * that nasid to determine if its partition needs to be activated or + * deactivated. + * + * A partition is consider "awaiting activation" if our partition + * flags indicate it is not active and it has a heartbeat. A + * partition is considered "awaiting deactivation" if our partition + * flags indicate it is active but it has no heartbeat or it is not + * sending its heartbeat to us. + * + * To determine the heartbeat, the remote nasid must have a properly + * initialized reserved page. + */ +static void +xpc_identify_act_IRQ_req(int nasid) +{ + struct xpc_rsvd_page *remote_rp; + struct xpc_vars *remote_vars; + u64 remote_rp_pa; + u64 remote_vars_pa; + int remote_rp_version; + int reactivate = 0; + int stamp_diff; + struct timespec remote_rp_stamp = { 0, 0 }; + partid_t partid; + struct xpc_partition *part; + enum xpc_retval ret; + + + /* pull over the reserved page structure */ + + remote_rp = (struct xpc_rsvd_page *) xpc_remote_copy_buffer; + + ret = xpc_get_remote_rp(nasid, NULL, remote_rp, &remote_rp_pa); + if (ret != xpcSuccess) { + dev_warn(xpc_part, "unable to get reserved page from nasid %d, " + "which sent interrupt, reason=%d\n", nasid, ret); + return; + } + + remote_vars_pa = remote_rp->vars_pa; + remote_rp_version = remote_rp->version; + if (XPC_SUPPORTS_RP_STAMP(remote_rp_version)) { + remote_rp_stamp = remote_rp->stamp; + } + partid = remote_rp->partid; + part = &xpc_partitions[partid]; + + + /* pull over the cross partition variables */ + + remote_vars = (struct xpc_vars *) xpc_remote_copy_buffer; + + ret = xpc_get_remote_vars(remote_vars_pa, remote_vars); + if (ret != xpcSuccess) { + + dev_warn(xpc_part, "unable to get XPC variables from nasid %d, " + "which sent interrupt, reason=%d\n", nasid, ret); + + XPC_DEACTIVATE_PARTITION(part, ret); + return; + } + + + part->act_IRQ_rcvd++; + + dev_dbg(xpc_part, "partid for nasid %d is %d; IRQs = %d; HB = " + "%ld:0x%lx\n", (int) nasid, (int) partid, part->act_IRQ_rcvd, + remote_vars->heartbeat, remote_vars->heartbeating_to_mask); + + if (xpc_partition_disengaged(part) && + part->act_state == XPC_P_INACTIVE) { + + xpc_update_partition_info(part, remote_rp_version, + &remote_rp_stamp, remote_rp_pa, + remote_vars_pa, remote_vars); + + if (XPC_SUPPORTS_DISENGAGE_REQUEST(part->remote_vars_version)) { + if (xpc_partition_disengage_requested(1UL << partid)) { + /* + * Other side is waiting on us to disengage, + * even though we already have. + */ + return; + } + } else { + /* other side doesn't support disengage requests */ + xpc_clear_partition_disengage_request(1UL << partid); + } + + xpc_activate_partition(part); + return; + } + + DBUG_ON(part->remote_rp_version == 0); + DBUG_ON(part->remote_vars_version == 0); + + if (!XPC_SUPPORTS_RP_STAMP(part->remote_rp_version)) { + DBUG_ON(XPC_SUPPORTS_DISENGAGE_REQUEST(part-> + remote_vars_version)); + + if (!XPC_SUPPORTS_RP_STAMP(remote_rp_version)) { + DBUG_ON(XPC_SUPPORTS_DISENGAGE_REQUEST(remote_vars-> + version)); + /* see if the other side rebooted */ + if (part->remote_amos_page_pa == + remote_vars->amos_page_pa && + xpc_hb_allowed(sn_partition_id, + remote_vars)) { + /* doesn't look that way, so ignore the IPI */ + return; + } + } + + /* + * Other side rebooted and previous XPC didn't support the + * disengage request, so we don't need to do anything special. + */ + + xpc_update_partition_info(part, remote_rp_version, + &remote_rp_stamp, remote_rp_pa, + remote_vars_pa, remote_vars); + part->reactivate_nasid = nasid; + XPC_DEACTIVATE_PARTITION(part, xpcReactivating); + return; + } + + DBUG_ON(!XPC_SUPPORTS_DISENGAGE_REQUEST(part->remote_vars_version)); + + if (!XPC_SUPPORTS_RP_STAMP(remote_rp_version)) { + DBUG_ON(!XPC_SUPPORTS_DISENGAGE_REQUEST(remote_vars->version)); + + /* + * Other side rebooted and previous XPC did support the + * disengage request, but the new one doesn't. + */ + + xpc_clear_partition_engaged(1UL << partid); + xpc_clear_partition_disengage_request(1UL << partid); + + xpc_update_partition_info(part, remote_rp_version, + &remote_rp_stamp, remote_rp_pa, + remote_vars_pa, remote_vars); + reactivate = 1; + + } else { + DBUG_ON(!XPC_SUPPORTS_DISENGAGE_REQUEST(remote_vars->version)); + + stamp_diff = xpc_compare_stamps(&part->remote_rp_stamp, + &remote_rp_stamp); + if (stamp_diff != 0) { + DBUG_ON(stamp_diff >= 0); + + /* + * Other side rebooted and the previous XPC did support + * the disengage request, as does the new one. + */ + + DBUG_ON(xpc_partition_engaged(1UL << partid)); + DBUG_ON(xpc_partition_disengage_requested(1UL << + partid)); + + xpc_update_partition_info(part, remote_rp_version, + &remote_rp_stamp, remote_rp_pa, + remote_vars_pa, remote_vars); + reactivate = 1; + } + } + + if (part->disengage_request_timeout > 0 && + !xpc_partition_disengaged(part)) { + /* still waiting on other side to disengage from us */ + return; + } + + if (reactivate) { + part->reactivate_nasid = nasid; + XPC_DEACTIVATE_PARTITION(part, xpcReactivating); + + } else if (XPC_SUPPORTS_DISENGAGE_REQUEST(part->remote_vars_version) && + xpc_partition_disengage_requested(1UL << partid)) { + XPC_DEACTIVATE_PARTITION(part, xpcOtherGoingDown); + } +} + + +/* + * Loop through the activation AMO variables and process any bits + * which are set. Each bit indicates a nasid sending a partition + * activation or deactivation request. + * + * Return #of IRQs detected. + */ +int +xpc_identify_act_IRQ_sender(void) +{ + int word, bit; + u64 nasid_mask; + u64 nasid; /* remote nasid */ + int n_IRQs_detected = 0; + AMO_t *act_amos; + + + act_amos = xpc_vars->amos_page + XPC_ACTIVATE_IRQ_AMOS; + + + /* scan through act AMO variable looking for non-zero entries */ + for (word = 0; word < xp_nasid_mask_words; word++) { + + if (xpc_exiting) { + break; + } + + nasid_mask = xpc_IPI_receive(&act_amos[word]); + if (nasid_mask == 0) { + /* no IRQs from nasids in this variable */ + continue; + } + + dev_dbg(xpc_part, "AMO[%d] gave back 0x%lx\n", word, + nasid_mask); + + + /* + * If this nasid has been added to the machine since + * our partition was reset, this will retain the + * remote nasid in our reserved pages machine mask. + * This is used in the event of module reload. + */ + xpc_mach_nasids[word] |= nasid_mask; + + + /* locate the nasid(s) which sent interrupts */ + + for (bit = 0; bit < (8 * sizeof(u64)); bit++) { + if (nasid_mask & (1UL << bit)) { + n_IRQs_detected++; + nasid = XPC_NASID_FROM_W_B(word, bit); + dev_dbg(xpc_part, "interrupt from nasid %ld\n", + nasid); + xpc_identify_act_IRQ_req(nasid); + } + } + } + return n_IRQs_detected; +} + + +/* + * See if the other side has responded to a partition disengage request + * from us. + */ +int +xpc_partition_disengaged(struct xpc_partition *part) +{ + partid_t partid = XPC_PARTID(part); + int disengaged; + + + disengaged = (xpc_partition_engaged(1UL << partid) == 0); + if (part->disengage_request_timeout) { + if (!disengaged) { + if (time_before(jiffies, part->disengage_request_timeout)) { + /* timelimit hasn't been reached yet */ + return 0; + } + + /* + * Other side hasn't responded to our disengage + * request in a timely fashion, so assume it's dead. + */ + + dev_info(xpc_part, "disengage from remote partition %d " + "timed out\n", partid); + xpc_disengage_request_timedout = 1; + xpc_clear_partition_engaged(1UL << partid); + disengaged = 1; + } + part->disengage_request_timeout = 0; + + /* cancel the timer function, provided it's not us */ + if (!in_interrupt()) { + del_singleshot_timer_sync(&part-> + disengage_request_timer); + } + + DBUG_ON(part->act_state != XPC_P_DEACTIVATING && + part->act_state != XPC_P_INACTIVE); + if (part->act_state != XPC_P_INACTIVE) { + xpc_wakeup_channel_mgr(part); + } + + if (XPC_SUPPORTS_DISENGAGE_REQUEST(part->remote_vars_version)) { + xpc_cancel_partition_disengage_request(part); + } + } + return disengaged; +} + + +/* + * Mark specified partition as active. + */ +enum xpc_retval +xpc_mark_partition_active(struct xpc_partition *part) +{ + unsigned long irq_flags; + enum xpc_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_ACTIVATING) { + part->act_state = XPC_P_ACTIVE; + ret = xpcSuccess; + } else { + DBUG_ON(part->reason == xpcSuccess); + ret = part->reason; + } + spin_unlock_irqrestore(&part->act_lock, irq_flags); + + return ret; +} + + +/* + * Notify XPC that the partition is down. + */ +void +xpc_deactivate_partition(const int line, struct xpc_partition *part, + enum xpc_retval reason) +{ + unsigned long irq_flags; + + + spin_lock_irqsave(&part->act_lock, irq_flags); + + if (part->act_state == XPC_P_INACTIVE) { + XPC_SET_REASON(part, reason, line); + spin_unlock_irqrestore(&part->act_lock, irq_flags); + if (reason == xpcReactivating) { + /* we interrupt ourselves to reactivate partition */ + xpc_IPI_send_reactivate(part); + } + return; + } + if (part->act_state == XPC_P_DEACTIVATING) { + if ((part->reason == xpcUnloading && reason != xpcUnloading) || + reason == xpcReactivating) { + XPC_SET_REASON(part, reason, line); + } + spin_unlock_irqrestore(&part->act_lock, irq_flags); + return; + } + + part->act_state = XPC_P_DEACTIVATING; + XPC_SET_REASON(part, reason, line); + + spin_unlock_irqrestore(&part->act_lock, irq_flags); + + if (XPC_SUPPORTS_DISENGAGE_REQUEST(part->remote_vars_version)) { + xpc_request_partition_disengage(part); + xpc_IPI_send_disengage(part); + + /* set a timelimit on the disengage request */ + part->disengage_request_timeout = jiffies + + (xpc_disengage_request_timelimit * HZ); + part->disengage_request_timer.expires = + part->disengage_request_timeout; + add_timer(&part->disengage_request_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_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; + struct xpc_vars *remote_vars; + u64 remote_rp_pa; + u64 remote_vars_pa; + int region; + int region_size; + int max_regions; + int nasid; + struct xpc_rsvd_page *rp; + partid_t partid; + struct xpc_partition *part; + u64 *discovered_nasids; + enum xpc_retval ret; + + + remote_rp = xpc_kmalloc_cacheline_aligned(XPC_RP_HEADER_SIZE + + xp_nasid_mask_bytes, + GFP_KERNEL, &remote_rp_base); + if (remote_rp == NULL) { + return; + } + remote_vars = (struct xpc_vars *) remote_rp; + + + discovered_nasids = kzalloc(sizeof(u64) * xp_nasid_mask_words, + 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. + */ + max_regions = 64; + region_size = sn_region_size; + + 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 ((volatile int) 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 ((volatile int) xpc_exiting) { + break; + } + + dev_dbg(xpc_part, "checking nasid %d\n", nasid); + + + if (XPC_NASID_IN_ARRAY(nasid, xpc_part_nasids)) { + dev_dbg(xpc_part, "PROM indicates Nasid %d is " + "part of the local partition; skipping " + "region\n", nasid); + break; + } + + if (!(XPC_NASID_IN_ARRAY(nasid, xpc_mach_nasids))) { + dev_dbg(xpc_part, "PROM indicates Nasid %d was " + "not on Numa-Link network at reset\n", + nasid); + continue; + } + + if (XPC_NASID_IN_ARRAY(nasid, discovered_nasids)) { + dev_dbg(xpc_part, "Nasid %d is part of a " + "partition which was previously " + "discovered\n", nasid); + continue; + } + + + /* pull over the reserved page structure */ + + ret = xpc_get_remote_rp(nasid, discovered_nasids, + remote_rp, &remote_rp_pa); + if (ret != xpcSuccess) { + dev_dbg(xpc_part, "unable to get reserved page " + "from nasid %d, reason=%d\n", nasid, + ret); + + if (ret == xpcLocalPartid) { + break; + } + continue; + } + + remote_vars_pa = remote_rp->vars_pa; + + partid = remote_rp->partid; + part = &xpc_partitions[partid]; + + + /* pull over the cross partition variables */ + + ret = xpc_get_remote_vars(remote_vars_pa, remote_vars); + if (ret != xpcSuccess) { + dev_dbg(xpc_part, "unable to get XPC variables " + "from nasid %d, reason=%d\n", nasid, + ret); + + XPC_DEACTIVATE_PARTITION(part, ret); + continue; + } + + if (part->act_state != XPC_P_INACTIVE) { + dev_dbg(xpc_part, "partition %d on nasid %d is " + "already activating\n", partid, nasid); + break; + } + + /* + * Register the remote partition's AMOs with SAL so it + * can handle and cleanup errors within that address + * range should the remote partition go down. We don't + * unregister this range because it is difficult to + * tell when outstanding writes to the remote partition + * are finished and thus when it is thus safe to + * unregister. This should not result in wasted space + * in the SAL xp_addr_region table because we should + * get the same page for remote_act_amos_pa after + * module reloads and system reboots. + */ + if (sn_register_xp_addr_region( + remote_vars->amos_page_pa, + PAGE_SIZE, 1) < 0) { + dev_dbg(xpc_part, "partition %d failed to " + "register xp_addr region 0x%016lx\n", + partid, remote_vars->amos_page_pa); + + XPC_SET_REASON(part, xpcPhysAddrRegFailed, + __LINE__); + break; + } + + /* + * The remote nasid is valid and available. + * Send an interrupt to that nasid to notify + * it that we are ready to begin activation. + */ + dev_dbg(xpc_part, "sending an interrupt to AMO 0x%lx, " + "nasid %d, phys_cpuid 0x%x\n", + remote_vars->amos_page_pa, + remote_vars->act_nasid, + remote_vars->act_phys_cpuid); + + if (XPC_SUPPORTS_DISENGAGE_REQUEST(remote_vars-> + version)) { + part->remote_amos_page_pa = + remote_vars->amos_page_pa; + xpc_mark_partition_disengaged(part); + xpc_cancel_partition_disengage_request(part); + } + xpc_IPI_send_activate(remote_vars); + } + } + + 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 xpc_retval +xpc_initiate_partid_to_nasids(partid_t partid, void *nasid_mask) +{ + struct xpc_partition *part; + u64 part_nasid_pa; + int bte_res; + + + part = &xpc_partitions[partid]; + if (part->remote_rp_pa == 0) { + return xpcPartitionDown; + } + + memset(nasid_mask, 0, XP_NASID_MASK_BYTES); + + part_nasid_pa = (u64) XPC_RP_PART_NASIDS(part->remote_rp_pa); + + bte_res = xp_bte_copy(part_nasid_pa, (u64) nasid_mask, + xp_nasid_mask_bytes, (BTE_NOTIFY | BTE_WACQUIRE), NULL); + + return xpc_map_bte_errors(bte_res); +} + |