diff options
Diffstat (limited to 'drivers/misc/sgi-xp/xpc_sn2.c')
| -rw-r--r-- | drivers/misc/sgi-xp/xpc_sn2.c | 1181 |
1 files changed, 1175 insertions, 6 deletions
diff --git a/drivers/misc/sgi-xp/xpc_sn2.c b/drivers/misc/sgi-xp/xpc_sn2.c index ee28e231dc47..89c0bb9a27f5 100644 --- a/drivers/misc/sgi-xp/xpc_sn2.c +++ b/drivers/misc/sgi-xp/xpc_sn2.c @@ -19,9 +19,370 @@ #include <asm/sn/sn_sal.h> #include "xpc.h" -struct xpc_vars *xpc_vars; +static struct xpc_vars_sn2 *xpc_vars; /* >>> Add _sn2 suffix? */ static struct xpc_vars_part_sn2 *xpc_vars_part; /* >>> Add _sn2 suffix? */ +/* + * The following set of macros and functions are used for the sending and + * receiving of IPIs (also known as IRQs). There are two flavors of IPIs, + * one that is associated with partition activity (SGI_XPC_ACTIVATE) and + * the other that is associated with channel activity (SGI_XPC_NOTIFY). + */ + +static u64 +xpc_IPI_receive_sn2(AMO_t *amo) +{ + return FETCHOP_LOAD_OP(TO_AMO((u64)&amo->variable), FETCHOP_CLEAR); +} + +static enum xp_retval +xpc_IPI_send_sn2(AMO_t *amo, u64 flag, int nasid, int phys_cpuid, int vector) +{ + int ret = 0; + unsigned long irq_flags; + + local_irq_save(irq_flags); + + FETCHOP_STORE_OP(TO_AMO((u64)&amo->variable), FETCHOP_OR, flag); + sn_send_IPI_phys(nasid, phys_cpuid, vector, 0); + + /* + * We must always use the nofault function regardless of whether we + * are on a Shub 1.1 system or a Shub 1.2 slice 0xc processor. If we + * didn't, we'd never know that the other partition is down and would + * keep sending IPIs and AMOs to it until the heartbeat times out. + */ + ret = xp_nofault_PIOR((u64 *)GLOBAL_MMR_ADDR(NASID_GET(&amo->variable), + xp_nofault_PIOR_target)); + + local_irq_restore(irq_flags); + + return ((ret == 0) ? xpSuccess : xpPioReadError); +} + +static AMO_t * +xpc_IPI_init_sn2(int index) +{ + AMO_t *amo = xpc_vars->amos_page + index; + + (void)xpc_IPI_receive_sn2(amo); /* clear AMO variable */ + return amo; +} + +/* + * IPIs associated with SGI_XPC_ACTIVATE IRQ. + */ + +/* + * Flag the appropriate AMO variable and send an IPI to the specified node. + */ +static void +xpc_activate_IRQ_send_sn2(u64 amos_page_pa, int from_nasid, int to_nasid, + int to_phys_cpuid) +{ + int w_index = XPC_NASID_W_INDEX(from_nasid); + int b_index = XPC_NASID_B_INDEX(from_nasid); + AMO_t *amos = (AMO_t *)__va(amos_page_pa + + (XPC_ACTIVATE_IRQ_AMOS * sizeof(AMO_t))); + + (void)xpc_IPI_send_sn2(&amos[w_index], (1UL << b_index), to_nasid, + to_phys_cpuid, SGI_XPC_ACTIVATE); +} + +static void +xpc_activate_IRQ_send_local_sn2(int from_nasid) +{ + int w_index = XPC_NASID_W_INDEX(from_nasid); + int b_index = XPC_NASID_B_INDEX(from_nasid); + AMO_t *amos = (AMO_t *)__va(xpc_vars->amos_page_pa + + (XPC_ACTIVATE_IRQ_AMOS * sizeof(AMO_t))); + + /* fake the sending and receipt of an activate IRQ from remote nasid */ + FETCHOP_STORE_OP(TO_AMO((u64)&amos[w_index].variable), FETCHOP_OR, + (1UL << b_index)); + atomic_inc(&xpc_act_IRQ_rcvd); + wake_up_interruptible(&xpc_act_IRQ_wq); +} + +static void +xpc_IPI_send_local_activate_sn2(int from_nasid) +{ + xpc_activate_IRQ_send_local_sn2(from_nasid); +} + +static void +xpc_IPI_send_activated_sn2(struct xpc_partition *part) +{ + xpc_activate_IRQ_send_sn2(part->remote_amos_page_pa, + cnodeid_to_nasid(0), part->remote_act_nasid, + part->remote_act_phys_cpuid); +} + +static void +xpc_IPI_send_local_reactivate_sn2(int from_nasid) +{ + xpc_activate_IRQ_send_local_sn2(from_nasid); +} + +static void +xpc_IPI_send_disengage_sn2(struct xpc_partition *part) +{ + xpc_activate_IRQ_send_sn2(part->remote_amos_page_pa, + cnodeid_to_nasid(0), part->remote_act_nasid, + part->remote_act_phys_cpuid); +} + +/* + * IPIs associated with SGI_XPC_NOTIFY IRQ. + */ + +/* + * Send an IPI to the remote partition that is associated with the + * specified channel. + */ +static void +xpc_notify_IRQ_send_sn2(struct xpc_channel *ch, u8 ipi_flag, + char *ipi_flag_string, unsigned long *irq_flags) +{ + struct xpc_partition *part = &xpc_partitions[ch->partid]; + enum xp_retval ret; + + if (likely(part->act_state != XPC_P_DEACTIVATING)) { + ret = xpc_IPI_send_sn2(part->remote_IPI_amo_va, + (u64)ipi_flag << (ch->number * 8), + part->remote_IPI_nasid, + part->remote_IPI_phys_cpuid, + SGI_XPC_NOTIFY); + dev_dbg(xpc_chan, "%s sent to partid=%d, channel=%d, ret=%d\n", + ipi_flag_string, ch->partid, ch->number, ret); + if (unlikely(ret != xpSuccess)) { + if (irq_flags != NULL) + spin_unlock_irqrestore(&ch->lock, *irq_flags); + XPC_DEACTIVATE_PARTITION(part, ret); + if (irq_flags != NULL) + spin_lock_irqsave(&ch->lock, *irq_flags); + } + } +} + +#define XPC_NOTIFY_IRQ_SEND_SN2(_ch, _ipi_f, _irq_f) \ + xpc_notify_IRQ_send_sn2(_ch, _ipi_f, #_ipi_f, _irq_f) + +/* + * Make it look like the remote partition, which is associated with the + * specified channel, sent us an IPI. This faked IPI will be handled + * by xpc_dropped_IPI_check(). + */ +static void +xpc_notify_IRQ_send_local_sn2(struct xpc_channel *ch, u8 ipi_flag, + char *ipi_flag_string) +{ + struct xpc_partition *part = &xpc_partitions[ch->partid]; + + FETCHOP_STORE_OP(TO_AMO((u64)&part->local_IPI_amo_va->variable), + FETCHOP_OR, ((u64)ipi_flag << (ch->number * 8))); + dev_dbg(xpc_chan, "%s sent local from partid=%d, channel=%d\n", + ipi_flag_string, ch->partid, ch->number); +} + +#define XPC_NOTIFY_IRQ_SEND_LOCAL_SN2(_ch, _ipi_f) \ + xpc_notify_IRQ_send_local_sn2(_ch, _ipi_f, #_ipi_f) + +static void +xpc_IPI_send_closerequest_sn2(struct xpc_channel *ch, unsigned long *irq_flags) +{ + struct xpc_openclose_args *args = ch->local_openclose_args; + + args->reason = ch->reason; + XPC_NOTIFY_IRQ_SEND_SN2(ch, XPC_IPI_CLOSEREQUEST, irq_flags); +} + +static void +xpc_IPI_send_closereply_sn2(struct xpc_channel *ch, unsigned long *irq_flags) +{ + XPC_NOTIFY_IRQ_SEND_SN2(ch, XPC_IPI_CLOSEREPLY, irq_flags); +} + +static void +xpc_IPI_send_openrequest_sn2(struct xpc_channel *ch, unsigned long *irq_flags) +{ + struct xpc_openclose_args *args = ch->local_openclose_args; + + args->msg_size = ch->msg_size; + args->local_nentries = ch->local_nentries; + XPC_NOTIFY_IRQ_SEND_SN2(ch, XPC_IPI_OPENREQUEST, irq_flags); +} + +static void +xpc_IPI_send_openreply_sn2(struct xpc_channel *ch, unsigned long *irq_flags) +{ + struct xpc_openclose_args *args = ch->local_openclose_args; + + args->remote_nentries = ch->remote_nentries; + args->local_nentries = ch->local_nentries; + args->local_msgqueue_pa = __pa(ch->local_msgqueue); + XPC_NOTIFY_IRQ_SEND_SN2(ch, XPC_IPI_OPENREPLY, irq_flags); +} + +static void +xpc_IPI_send_msgrequest_sn2(struct xpc_channel *ch) +{ + XPC_NOTIFY_IRQ_SEND_SN2(ch, XPC_IPI_MSGREQUEST, NULL); +} + +static void +xpc_IPI_send_local_msgrequest_sn2(struct xpc_channel *ch) +{ + XPC_NOTIFY_IRQ_SEND_LOCAL_SN2(ch, XPC_IPI_MSGREQUEST); +} + +/* + * This next set of functions are used to keep track of when a partition is + * potentially engaged in accessing memory belonging to another partition. + */ + +static void +xpc_mark_partition_engaged_sn2(struct xpc_partition *part) +{ + unsigned long irq_flags; + AMO_t *amo = (AMO_t *)__va(part->remote_amos_page_pa + + (XPC_ENGAGED_PARTITIONS_AMO * + sizeof(AMO_t))); + + local_irq_save(irq_flags); + + /* set bit corresponding to our partid in remote partition's AMO */ + FETCHOP_STORE_OP(TO_AMO((u64)&amo->variable), FETCHOP_OR, + (1UL << sn_partition_id)); + /* + * We must always use the nofault function regardless of whether we + * are on a Shub 1.1 system or a Shub 1.2 slice 0xc processor. If we + * didn't, we'd never know that the other partition is down and would + * keep sending IPIs and AMOs to it until the heartbeat times out. + */ + (void)xp_nofault_PIOR((u64 *)GLOBAL_MMR_ADDR(NASID_GET(&amo-> + variable), + xp_nofault_PIOR_target)); + + local_irq_restore(irq_flags); +} + +static void +xpc_mark_partition_disengaged_sn2(struct xpc_partition *part) +{ + unsigned long irq_flags; + AMO_t *amo = (AMO_t *)__va(part->remote_amos_page_pa + + (XPC_ENGAGED_PARTITIONS_AMO * + sizeof(AMO_t))); + + local_irq_save(irq_flags); + + /* clear bit corresponding to our partid in remote partition's AMO */ + FETCHOP_STORE_OP(TO_AMO((u64)&amo->variable), FETCHOP_AND, + ~(1UL << sn_partition_id)); + /* + * We must always use the nofault function regardless of whether we + * are on a Shub 1.1 system or a Shub 1.2 slice 0xc processor. If we + * didn't, we'd never know that the other partition is down and would + * keep sending IPIs and AMOs to it until the heartbeat times out. + */ + (void)xp_nofault_PIOR((u64 *)GLOBAL_MMR_ADDR(NASID_GET(&amo-> + variable), + xp_nofault_PIOR_target)); + + local_irq_restore(irq_flags); +} + +static void +xpc_request_partition_disengage_sn2(struct xpc_partition *part) +{ + unsigned long irq_flags; + AMO_t *amo = (AMO_t *)__va(part->remote_amos_page_pa + + (XPC_DISENGAGE_REQUEST_AMO * sizeof(AMO_t))); + + local_irq_save(irq_flags); + + /* set bit corresponding to our partid in remote partition's AMO */ + FETCHOP_STORE_OP(TO_AMO((u64)&amo->variable), FETCHOP_OR, + (1UL << sn_partition_id)); + /* + * We must always use the nofault function regardless of whether we + * are on a Shub 1.1 system or a Shub 1.2 slice 0xc processor. If we + * didn't, we'd never know that the other partition is down and would + * keep sending IPIs and AMOs to it until the heartbeat times out. + */ + (void)xp_nofault_PIOR((u64 *)GLOBAL_MMR_ADDR(NASID_GET(&amo-> + variable), + xp_nofault_PIOR_target)); + + local_irq_restore(irq_flags); +} + +static void +xpc_cancel_partition_disengage_request_sn2(struct xpc_partition *part) +{ + unsigned long irq_flags; + AMO_t *amo = (AMO_t *)__va(part->remote_amos_page_pa + + (XPC_DISENGAGE_REQUEST_AMO * sizeof(AMO_t))); + + local_irq_save(irq_flags); + + /* clear bit corresponding to our partid in remote partition's AMO */ + FETCHOP_STORE_OP(TO_AMO((u64)&amo->variable), FETCHOP_AND, + ~(1UL << sn_partition_id)); + /* + * We must always use the nofault function regardless of whether we + * are on a Shub 1.1 system or a Shub 1.2 slice 0xc processor. If we + * didn't, we'd never know that the other partition is down and would + * keep sending IPIs and AMOs to it until the heartbeat times out. + */ + (void)xp_nofault_PIOR((u64 *)GLOBAL_MMR_ADDR(NASID_GET(&amo-> + variable), + xp_nofault_PIOR_target)); + + local_irq_restore(irq_flags); +} + +static u64 +xpc_partition_engaged_sn2(u64 partid_mask) +{ + AMO_t *amo = xpc_vars->amos_page + XPC_ENGAGED_PARTITIONS_AMO; + + /* return our partition's AMO variable ANDed with partid_mask */ + return (FETCHOP_LOAD_OP(TO_AMO((u64)&amo->variable), FETCHOP_LOAD) & + partid_mask); +} + +static u64 +xpc_partition_disengage_requested_sn2(u64 partid_mask) +{ + AMO_t *amo = xpc_vars->amos_page + XPC_DISENGAGE_REQUEST_AMO; + + /* return our partition's AMO variable ANDed with partid_mask */ + return (FETCHOP_LOAD_OP(TO_AMO((u64)&amo->variable), FETCHOP_LOAD) & + partid_mask); +} + +static void +xpc_clear_partition_engaged_sn2(u64 partid_mask) +{ + AMO_t *amo = xpc_vars->amos_page + XPC_ENGAGED_PARTITIONS_AMO; + + /* clear bit(s) based on partid_mask in our partition's AMO */ + FETCHOP_STORE_OP(TO_AMO((u64)&amo->variable), FETCHOP_AND, + ~partid_mask); +} + +static void +xpc_clear_partition_disengage_request_sn2(u64 partid_mask) +{ + AMO_t *amo = xpc_vars->amos_page + XPC_DISENGAGE_REQUEST_AMO; + + /* clear bit(s) based on partid_mask in our partition's AMO */ + FETCHOP_STORE_OP(TO_AMO((u64)&amo->variable), FETCHOP_AND, + ~partid_mask); +} + static enum xp_retval xpc_rsvd_page_init_sn2(struct xpc_rsvd_page *rp) { @@ -79,7 +440,7 @@ xpc_rsvd_page_init_sn2(struct xpc_rsvd_page *rp) } /* clear xpc_vars */ - memset(xpc_vars, 0, sizeof(struct xpc_vars)); + memset(xpc_vars, 0, sizeof(struct xpc_vars_sn2)); xpc_vars->version = XPC_V_VERSION; xpc_vars->act_nasid = cpuid_to_nasid(0); @@ -94,15 +455,446 @@ xpc_rsvd_page_init_sn2(struct xpc_rsvd_page *rp) /* 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); + (void)xpc_IPI_init_sn2(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); + (void)xpc_IPI_init_sn2(XPC_ENGAGED_PARTITIONS_AMO); + (void)xpc_IPI_init_sn2(XPC_DISENGAGE_REQUEST_AMO); + + return xpSuccess; +} + +static void +xpc_increment_heartbeat_sn2(void) +{ + xpc_vars->heartbeat++; +} + +static void +xpc_offline_heartbeat_sn2(void) +{ + xpc_increment_heartbeat_sn2(); + xpc_vars->heartbeat_offline = 1; +} + +static void +xpc_online_heartbeat_sn2(void) +{ + xpc_increment_heartbeat_sn2(); + xpc_vars->heartbeat_offline = 0; +} + +static void +xpc_heartbeat_init_sn2(void) +{ + DBUG_ON(xpc_vars == NULL); + + bitmap_zero(xpc_vars->heartbeating_to_mask, XP_MAX_NPARTITIONS_SN2); + xpc_heartbeating_to_mask = &xpc_vars->heartbeating_to_mask[0]; + xpc_online_heartbeat_sn2(); +} + +static void +xpc_heartbeat_exit_sn2(void) +{ + xpc_offline_heartbeat_sn2(); +} + +/* + * At periodic intervals, scan through all active partitions and ensure + * their heartbeat is still active. If not, the partition is deactivated. + */ +static void +xpc_check_remote_hb_sn2(void) +{ + struct xpc_vars_sn2 *remote_vars; + struct xpc_partition *part; + short partid; + enum xp_retval ret; + + remote_vars = (struct xpc_vars_sn2 *)xpc_remote_copy_buffer; + + for (partid = 0; partid < xp_max_npartitions; 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 */ + ret = xp_remote_memcpy(remote_vars, + (void *)part->remote_vars_pa, + XPC_RP_VARS_SIZE); + if (ret != xpSuccess) { + XPC_DEACTIVATE_PARTITION(part, ret); + continue; + } + + dev_dbg(xpc_part, "partid = %d, heartbeat = %ld, last_heartbeat" + " = %ld, heartbeat_offline = %ld, HB_mask[0] = 0x%lx\n", + partid, remote_vars->heartbeat, part->last_heartbeat, + remote_vars->heartbeat_offline, + remote_vars->heartbeating_to_mask[0]); + + if (((remote_vars->heartbeat == part->last_heartbeat) && + (remote_vars->heartbeat_offline == 0)) || + !xpc_hb_allowed(sn_partition_id, + &remote_vars->heartbeating_to_mask)) { + + XPC_DEACTIVATE_PARTITION(part, xpNoHeartbeat); + continue; + } + + part->last_heartbeat = remote_vars->heartbeat; + } +} + +/* + * 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 xp_retval +xpc_get_remote_vars_sn2(u64 remote_vars_pa, struct xpc_vars_sn2 *remote_vars) +{ + enum xp_retval ret; + + if (remote_vars_pa == 0) + return xpVarsNotSet; + + /* pull over the cross partition variables */ + ret = xp_remote_memcpy(remote_vars, (void *)remote_vars_pa, + XPC_RP_VARS_SIZE); + if (ret != xpSuccess) + return ret; + + if (XPC_VERSION_MAJOR(remote_vars->version) != + XPC_VERSION_MAJOR(XPC_V_VERSION)) { + return xpBadVersion; + } return xpSuccess; } +static void +xpc_initiate_partition_activation_sn2(struct xpc_rsvd_page *remote_rp, + u64 remote_rp_pa, int nasid) +{ + xpc_IPI_send_local_activate(nasid); +} + +/* + * Update the remote partition's info. + */ +static void +xpc_update_partition_info_sn2(struct xpc_partition *part, u8 remote_rp_version, + struct timespec *remote_rp_stamp, + u64 remote_rp_pa, u64 remote_vars_pa, + struct xpc_vars_sn2 *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_sn2(int nasid) +{ + struct xpc_rsvd_page *remote_rp; + struct xpc_vars_sn2 *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 }; /*>>> ZERO_STAMP */ + short partid; + struct xpc_partition *part; + enum xp_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 != xpSuccess) { + 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->sn.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->SAL_partid; + part = &xpc_partitions[partid]; + + /* pull over the cross partition variables */ + + remote_vars = (struct xpc_vars_sn2 *)xpc_remote_copy_buffer; + + ret = xpc_get_remote_vars_sn2(remote_vars_pa, remote_vars); + if (ret != xpSuccess) { + + 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[0]); + + if (xpc_partition_disengaged(part) && + part->act_state == XPC_P_INACTIVE) { + + xpc_update_partition_info_sn2(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->heartbeating_to_mask)) { + /* 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_sn2(part, remote_rp_version, + &remote_rp_stamp, remote_rp_pa, + remote_vars_pa, remote_vars); + part->reactivate_nasid = nasid; + XPC_DEACTIVATE_PARTITION(part, xpReactivating); + 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_sn2(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_sn2(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, xpReactivating); + + } else if (XPC_SUPPORTS_DISENGAGE_REQUEST(part->remote_vars_version) && + xpc_partition_disengage_requested(1UL << partid)) { + XPC_DEACTIVATE_PARTITION(part, xpOtherGoingDown); + } +} + +/* + * 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_sn2(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_sn2(&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_sn2(nasid); + } + } + } + return n_IRQs_detected; +} + +static void +xpc_process_act_IRQ_rcvd_sn2(int n_IRQs_expected) +{ + int n_IRQs_detected; + + n_IRQs_detected = xpc_identify_act_IRQ_sender_sn2(); + if (n_IRQs_detected < n_IRQs_expected) { + /* retry once to help avoid missing AMO */ + (void)xpc_identify_act_IRQ_sender_sn2(); + } +} + /* * Setup the infrastructure necessary to support XPartition Communication * between the specified remote partition and the local one. @@ -177,7 +969,7 @@ xpc_setup_infrastructure_sn2(struct xpc_partition *part) part->remote_openclose_args_pa = 0; - part->local_IPI_amo_va = xpc_IPI_init(partid); + part->local_IPI_amo_va = xpc_IPI_init_sn2(partid); part->local_IPI_amo = 0; spin_lock_init(&part->IPI_lock); @@ -468,6 +1260,28 @@ xpc_make_first_contact_sn2(struct xpc_partition *part) { enum xp_retval ret; + /* + * 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 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_amos_page_pa after module + * reloads and system reboots. + */ + if (sn_register_xp_addr_region(part->remote_amos_page_pa, + PAGE_SIZE, 1) < 0) { + dev_warn(xpc_part, "xpc_activating(%d) failed to register " + "xp_addr region\n", XPC_PARTID(part)); + + ret = xpPhysAddrRegFailed; + XPC_DEACTIVATE_PARTITION(part, ret); + return ret; + } + + xpc_IPI_send_activated(part); + while ((ret = xpc_pull_remote_vars_part_sn2(part)) != xpSuccess) { if (ret != xpRetry) { XPC_DEACTIVATE_PARTITION(part, ret); @@ -651,15 +1465,370 @@ xpc_get_deliverable_msg_sn2(struct xpc_channel *ch) return msg; } +/* + * Now we actually send the messages that are ready to be sent by advancing + * the local message queue's Put value and then send an IPI to the recipient + * partition. + */ +static void +xpc_send_msgs_sn2(struct xpc_channel *ch, s64 initial_put) +{ + struct xpc_msg *msg; + s64 put = initial_put + 1; + int send_IPI = 0; + + while (1) { + + while (1) { + if (put == ch->w_local_GP.put) + break; + + msg = (struct xpc_msg *)((u64)ch->local_msgqueue + + (put % ch->local_nentries) * + ch->msg_size); + + if (!(msg->flags & XPC_M_READY)) + break; + + put++; + } + + if (put == initial_put) { + /* nothing's changed */ + break; + } + + if (cmpxchg_rel(&ch->local_GP->put, initial_put, put) != + initial_put) { + /* someone else beat us to it */ + DBUG_ON(ch->local_GP->put < initial_put); + break; + } + + /* we just set the new value of local_GP->put */ + + dev_dbg(xpc_chan, "local_GP->put changed to %ld, partid=%d, " + "channel=%d\n", put, ch->partid, ch->number); + + send_IPI = 1; + + /* + * We need to ensure that the message referenced by + * local_GP->put is not XPC_M_READY or that local_GP->put + * equals w_local_GP.put, so we'll go have a look. + */ + initial_put = put; + } + + if (send_IPI) + xpc_IPI_send_msgrequest_sn2(ch); +} + +/* + * Allocate an entry for a message from the message queue associated with the + * specified channel. + */ +static enum xp_retval +xpc_allocate_msg_sn2(struct xpc_channel *ch, u32 flags, + struct xpc_msg **address_of_msg) +{ + struct xpc_msg *msg; + enum xp_retval ret; + s64 put; + + /* this reference will be dropped in xpc_send_msg_sn2() */ + xpc_msgqueue_ref(ch); + + if (ch->flags & XPC_C_DISCONNECTING) { + xpc_msgqueue_deref(ch); + return ch->reason; + } + if (!(ch->flags & XPC_C_CONNECTED)) { + xpc_msgqueue_deref(ch); + return xpNotConnected; + } + + /* + * Get the next available message entry from the local message queue. + * If none are available, we'll make sure that we grab the latest + * GP values. + */ + ret = xpTimeout; + + while (1) { + + put = ch->w_local_GP.put; + rmb(); /* guarantee that .put loads before .get */ + if (put - ch->w_remote_GP.get < ch->local_nentries) { + + /* There are available message entries. We need to try + * to secure one for ourselves. We'll do this by trying + * to increment w_local_GP.put as long as someone else + * doesn't beat us to it. If they do, we'll have to + * try again. + */ + if (cmpxchg(&ch->w_local_GP.put, put, put + 1) == put) { + /* we got the entry referenced by put */ + break; + } + continue; /* try again */ + } + + /* + * There aren't any available msg entries at this time. + * + * In waiting for a message entry to become available, + * we set a timeout in case the other side is not + * sending completion IPIs. This lets us fake an IPI + * that will cause the IPI handler to fetch the latest + * GP values as if an IPI was sent by the other side. + */ + if (ret == xpTimeout) + xpc_IPI_send_local_msgrequest_sn2(ch); + + if (flags & XPC_NOWAIT) { + xpc_msgqueue_deref(ch); + return xpNoWait; + } + + ret = xpc_allocate_msg_wait(ch); + if (ret != xpInterrupted && ret != xpTimeout) { + xpc_msgqueue_deref(ch); + return ret; + } + } + + /* get the message's address and initialize it */ + msg = (struct xpc_msg *)((u64)ch->local_msgqueue + + (put % ch->local_nentries) * ch->msg_size); + + DBUG_ON(msg->flags != 0); + msg->number = put; + + dev_dbg(xpc_chan, "w_local_GP.put changed to %ld; msg=0x%p, " + "msg_number=%ld, partid=%d, channel=%d\n", put + 1, + (void *)msg, msg->number, ch->partid, ch->number); + + *address_of_msg = msg; + + return xpSuccess; +} + +/* + * Common code that does the actual sending of the message by advancing the + * local message queue's Put value and sends an IPI to the partition the + * message is being sent to. + */ +static enum xp_retval +xpc_send_msg_sn2(struct xpc_channel *ch, struct xpc_msg *msg, u8 notify_type, + xpc_notify_func func, void *key) +{ + enum xp_retval ret = xpSuccess; + struct xpc_notify *notify = notify; + s64 put, msg_number = msg->number; + + DBUG_ON(notify_type == XPC_N_CALL && func == NULL); + DBUG_ON((((u64)msg - (u64)ch->local_msgqueue) / ch->msg_size) != + msg_number % ch->local_nentries); + DBUG_ON(msg->flags & XPC_M_READY); + + if (ch->flags & XPC_C_DISCONNECTING) { + /* drop the reference grabbed in xpc_allocate_msg_sn2() */ + xpc_msgqueue_deref(ch); + return ch->reason; + } + + if (notify_type != 0) { + /* + * Tell the remote side to send an ACK interrupt when the + * message has been delivered. + */ + msg->flags |= XPC_M_INTERRUPT; + + atomic_inc(&ch->n_to_notify); + + notify = &ch->notify_queue[msg_number % ch->local_nentries]; + notify->func = func; + notify->key = key; + notify->type = notify_type; + + /* >>> is a mb() needed here? */ + + if (ch->flags & XPC_C_DISCONNECTING) { + /* + * An error occurred between our last error check and + * this one. We will try to clear the type field from + * the notify entry. If we succeed then + * xpc_disconnect_channel() didn't already process + * the notify entry. + */ + if (cmpxchg(¬ify->type, notify_type, 0) == + notify_type) { + atomic_dec(&ch->n_to_notify); + ret = ch->reason; + } + + /* drop reference grabbed in xpc_allocate_msg_sn2() */ + xpc_msgqueue_deref(ch); + return ret; + } + } + + msg->flags |= XPC_M_READY; + + /* + * The preceding store of msg->flags must occur before the following + * load of ch->local_GP->put. + */ + mb(); + + /* see if the message is next in line to be sent, if so send it */ + + put = ch->local_GP->put; + if (put == msg_number) + xpc_send_msgs_sn2(ch, put); + + /* drop the reference grabbed in xpc_allocate_msg_sn2() */ + xpc_msgqueue_deref(ch); + return ret; +} + +/* + * Now we actually acknowledge the messages that have been delivered and ack'd + * by advancing the cached remote message queue's Get value and if requested + * send an IPI to the message sender's partition. + */ +static void +xpc_acknowledge_msgs_sn2(struct xpc_channel *ch, s64 initial_get, u8 msg_flags) +{ + struct xpc_msg *msg; + s64 get = initial_get + 1; + int send_IPI = 0; + + while (1) { + + while (1) { + if (get == ch->w_local_GP.get) + break; + + msg = (struct xpc_msg *)((u64)ch->remote_msgqueue + + (get % ch->remote_nentries) * + ch->msg_size); + + if (!(msg->flags & XPC_M_DONE)) + break; + + msg_flags |= msg->flags; + get++; + } + + if (get == initial_get) { + /* nothing's changed */ + break; + } + + if (cmpxchg_rel(&ch->local_GP->get, initial_get, get) != + initial_get) { + /* someone else beat us to it */ + DBUG_ON(ch->local_GP->get <= initial_get); + break; + } + + /* we just set the new value of local_GP->get */ + + dev_dbg(xpc_chan, "local_GP->get changed to %ld, partid=%d, " + "channel=%d\n", get, ch->partid, ch->number); + + send_IPI = (msg_flags & XPC_M_INTERRUPT); + + /* + * We need to ensure that the message referenced by + * local_GP->get is not XPC_M_DONE or that local_GP->get + * equals w_local_GP.get, so we'll go have a look. + */ + initial_get = get; + } + + if (send_IPI) + xpc_IPI_send_msgrequest_sn2(ch); +} + +static void +xpc_received_msg_sn2(struct xpc_channel *ch, struct xpc_msg *msg) +{ + s64 get; + s64 msg_number = msg->number; + + dev_dbg(xpc_chan, "msg=0x%p, msg_number=%ld, partid=%d, channel=%d\n", + (void *)msg, msg_number, ch->partid, ch->number); + + DBUG_ON((((u64)msg - (u64)ch->remote_msgqueue) / ch->msg_size) != + msg_number % ch->remote_nentries); + DBUG_ON(msg->flags & XPC_M_DONE); + + msg->flags |= XPC_M_DONE; + + /* + * The preceding store of msg->flags must occur before the following + * load of ch->local_GP->get. + */ + mb(); + + /* + * See if this message is next in line to be acknowledged as having + * been delivered. + */ + get = ch->local_GP->get; + if (get == msg_number) + xpc_acknowledge_msgs_sn2(ch, get, msg->flags); +} + void xpc_init_sn2(void) { xpc_rsvd_page_init = xpc_rsvd_page_init_sn2; + xpc_increment_heartbeat = xpc_increment_heartbeat_sn2; + xpc_offline_heartbeat = xpc_offline_heartbeat_sn2; + xpc_online_heartbeat = xpc_online_heartbeat_sn2; + xpc_heartbeat_init = xpc_heartbeat_init_sn2; + xpc_heartbeat_exit = xpc_heartbeat_exit_sn2; + xpc_check_remote_hb = xpc_check_remote_hb_sn2; + + xpc_initiate_partition_activation = + xpc_initiate_partition_activation_sn2; + xpc_process_act_IRQ_rcvd = xpc_process_act_IRQ_rcvd_sn2; xpc_setup_infrastructure = xpc_setup_infrastructure_sn2; xpc_teardown_infrastructure = xpc_teardown_infrastructure_sn2; xpc_make_first_contact = xpc_make_first_contact_sn2; xpc_get_IPI_flags = xpc_get_IPI_flags_sn2; xpc_get_deliverable_msg = xpc_get_deliverable_msg_sn2; + + xpc_mark_partition_engaged = xpc_mark_partition_engaged_sn2; + xpc_mark_partition_disengaged = xpc_mark_partition_disengaged_sn2; + xpc_request_partition_disengage = xpc_request_partition_disengage_sn2; + xpc_cancel_partition_disengage_request = + xpc_cancel_partition_disengage_request_sn2; + xpc_partition_engaged = xpc_partition_engaged_sn2; + xpc_partition_disengage_requested = + xpc_partition_disengage_requested_sn2; + xpc_clear_partition_engaged = xpc_clear_partition_engaged_sn2; + xpc_clear_partition_disengage_request = + xpc_clear_partition_disengage_request_sn2; + + xpc_IPI_send_local_activate = xpc_IPI_send_local_activate_sn2; + xpc_IPI_send_activated = xpc_IPI_send_activated_sn2; + xpc_IPI_send_local_reactivate = xpc_IPI_send_local_reactivate_sn2; + xpc_IPI_send_disengage = xpc_IPI_send_disengage_sn2; + + xpc_IPI_send_closerequest = xpc_IPI_send_closerequest_sn2; + xpc_IPI_send_closereply = xpc_IPI_send_closereply_sn2; + xpc_IPI_send_openrequest = xpc_IPI_send_openrequest_sn2; + xpc_IPI_send_openreply = xpc_IPI_send_openreply_sn2; + + xpc_allocate_msg = xpc_allocate_msg_sn2; + + xpc_send_msg = xpc_send_msg_sn2; + xpc_received_msg = xpc_received_msg_sn2; } void |