diff options
Diffstat (limited to 'drivers/misc/sgi-xp/xpc_partition.c')
-rw-r--r-- | drivers/misc/sgi-xp/xpc_partition.c | 540 |
1 files changed, 540 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 000000000..519826ba1 --- /dev/null +++ b/drivers/misc/sgi-xp/xpc_partition.c @@ -0,0 +1,540 @@ +/* + * 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 = NULL; + 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; + 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 = kcalloc(xpc_nasid_mask_nlongs, sizeof(long), + GFP_KERNEL); + if (discovered_nasids == NULL) { + kfree(remote_rp_base); + return; + } + + /* + * 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; + /* fall through */ + case 64: + max_regions *= 2; + /* fall through */ + 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); +} |