diff options
Diffstat (limited to 'drivers/misc/sgi-gru/grufault.c')
| -rw-r--r-- | drivers/misc/sgi-gru/grufault.c | 903 |
1 files changed, 903 insertions, 0 deletions
diff --git a/drivers/misc/sgi-gru/grufault.c b/drivers/misc/sgi-gru/grufault.c new file mode 100644 index 000000000..b836936e9 --- /dev/null +++ b/drivers/misc/sgi-gru/grufault.c @@ -0,0 +1,903 @@ +// SPDX-License-Identifier: GPL-2.0-or-later +/* + * SN Platform GRU Driver + * + * FAULT HANDLER FOR GRU DETECTED TLB MISSES + * + * This file contains code that handles TLB misses within the GRU. + * These misses are reported either via interrupts or user polling of + * the user CB. + * + * Copyright (c) 2008 Silicon Graphics, Inc. All Rights Reserved. + */ + +#include <linux/kernel.h> +#include <linux/errno.h> +#include <linux/spinlock.h> +#include <linux/mm.h> +#include <linux/hugetlb.h> +#include <linux/device.h> +#include <linux/io.h> +#include <linux/uaccess.h> +#include <linux/security.h> +#include <linux/sync_core.h> +#include <linux/prefetch.h> +#include "gru.h" +#include "grutables.h" +#include "grulib.h" +#include "gru_instructions.h" +#include <asm/uv/uv_hub.h> + +/* Return codes for vtop functions */ +#define VTOP_SUCCESS 0 +#define VTOP_INVALID -1 +#define VTOP_RETRY -2 + + +/* + * Test if a physical address is a valid GRU GSEG address + */ +static inline int is_gru_paddr(unsigned long paddr) +{ + return paddr >= gru_start_paddr && paddr < gru_end_paddr; +} + +/* + * Find the vma of a GRU segment. Caller must hold mmap_lock. + */ +struct vm_area_struct *gru_find_vma(unsigned long vaddr) +{ + struct vm_area_struct *vma; + + vma = vma_lookup(current->mm, vaddr); + if (vma && vma->vm_ops == &gru_vm_ops) + return vma; + return NULL; +} + +/* + * Find and lock the gts that contains the specified user vaddr. + * + * Returns: + * - *gts with the mmap_lock locked for read and the GTS locked. + * - NULL if vaddr invalid OR is not a valid GSEG vaddr. + */ + +static struct gru_thread_state *gru_find_lock_gts(unsigned long vaddr) +{ + struct mm_struct *mm = current->mm; + struct vm_area_struct *vma; + struct gru_thread_state *gts = NULL; + + mmap_read_lock(mm); + vma = gru_find_vma(vaddr); + if (vma) + gts = gru_find_thread_state(vma, TSID(vaddr, vma)); + if (gts) + mutex_lock(>s->ts_ctxlock); + else + mmap_read_unlock(mm); + return gts; +} + +static struct gru_thread_state *gru_alloc_locked_gts(unsigned long vaddr) +{ + struct mm_struct *mm = current->mm; + struct vm_area_struct *vma; + struct gru_thread_state *gts = ERR_PTR(-EINVAL); + + mmap_write_lock(mm); + vma = gru_find_vma(vaddr); + if (!vma) + goto err; + + gts = gru_alloc_thread_state(vma, TSID(vaddr, vma)); + if (IS_ERR(gts)) + goto err; + mutex_lock(>s->ts_ctxlock); + mmap_write_downgrade(mm); + return gts; + +err: + mmap_write_unlock(mm); + return gts; +} + +/* + * Unlock a GTS that was previously locked with gru_find_lock_gts(). + */ +static void gru_unlock_gts(struct gru_thread_state *gts) +{ + mutex_unlock(>s->ts_ctxlock); + mmap_read_unlock(current->mm); +} + +/* + * Set a CB.istatus to active using a user virtual address. This must be done + * just prior to a TFH RESTART. The new cb.istatus is an in-cache status ONLY. + * If the line is evicted, the status may be lost. The in-cache update + * is necessary to prevent the user from seeing a stale cb.istatus that will + * change as soon as the TFH restart is complete. Races may cause an + * occasional failure to clear the cb.istatus, but that is ok. + */ +static void gru_cb_set_istatus_active(struct gru_instruction_bits *cbk) +{ + if (cbk) { + cbk->istatus = CBS_ACTIVE; + } +} + +/* + * Read & clear a TFM + * + * The GRU has an array of fault maps. A map is private to a cpu + * Only one cpu will be accessing a cpu's fault map. + * + * This function scans the cpu-private fault map & clears all bits that + * are set. The function returns a bitmap that indicates the bits that + * were cleared. Note that sense the maps may be updated asynchronously by + * the GRU, atomic operations must be used to clear bits. + */ +static void get_clear_fault_map(struct gru_state *gru, + struct gru_tlb_fault_map *imap, + struct gru_tlb_fault_map *dmap) +{ + unsigned long i, k; + struct gru_tlb_fault_map *tfm; + + tfm = get_tfm_for_cpu(gru, gru_cpu_fault_map_id()); + prefetchw(tfm); /* Helps on hardware, required for emulator */ + for (i = 0; i < BITS_TO_LONGS(GRU_NUM_CBE); i++) { + k = tfm->fault_bits[i]; + if (k) + k = xchg(&tfm->fault_bits[i], 0UL); + imap->fault_bits[i] = k; + k = tfm->done_bits[i]; + if (k) + k = xchg(&tfm->done_bits[i], 0UL); + dmap->fault_bits[i] = k; + } + + /* + * Not functionally required but helps performance. (Required + * on emulator) + */ + gru_flush_cache(tfm); +} + +/* + * Atomic (interrupt context) & non-atomic (user context) functions to + * convert a vaddr into a physical address. The size of the page + * is returned in pageshift. + * returns: + * 0 - successful + * < 0 - error code + * 1 - (atomic only) try again in non-atomic context + */ +static int non_atomic_pte_lookup(struct vm_area_struct *vma, + unsigned long vaddr, int write, + unsigned long *paddr, int *pageshift) +{ + struct page *page; + +#ifdef CONFIG_HUGETLB_PAGE + *pageshift = is_vm_hugetlb_page(vma) ? HPAGE_SHIFT : PAGE_SHIFT; +#else + *pageshift = PAGE_SHIFT; +#endif + if (get_user_pages(vaddr, 1, write ? FOLL_WRITE : 0, &page, NULL) <= 0) + return -EFAULT; + *paddr = page_to_phys(page); + put_page(page); + return 0; +} + +/* + * atomic_pte_lookup + * + * Convert a user virtual address to a physical address + * Only supports Intel large pages (2MB only) on x86_64. + * ZZZ - hugepage support is incomplete + * + * NOTE: mmap_lock is already held on entry to this function. This + * guarantees existence of the page tables. + */ +static int atomic_pte_lookup(struct vm_area_struct *vma, unsigned long vaddr, + int write, unsigned long *paddr, int *pageshift) +{ + pgd_t *pgdp; + p4d_t *p4dp; + pud_t *pudp; + pmd_t *pmdp; + pte_t pte; + + pgdp = pgd_offset(vma->vm_mm, vaddr); + if (unlikely(pgd_none(*pgdp))) + goto err; + + p4dp = p4d_offset(pgdp, vaddr); + if (unlikely(p4d_none(*p4dp))) + goto err; + + pudp = pud_offset(p4dp, vaddr); + if (unlikely(pud_none(*pudp))) + goto err; + + pmdp = pmd_offset(pudp, vaddr); + if (unlikely(pmd_none(*pmdp))) + goto err; +#ifdef CONFIG_X86_64 + if (unlikely(pmd_large(*pmdp))) + pte = *(pte_t *) pmdp; + else +#endif + pte = *pte_offset_kernel(pmdp, vaddr); + + if (unlikely(!pte_present(pte) || + (write && (!pte_write(pte) || !pte_dirty(pte))))) + return 1; + + *paddr = pte_pfn(pte) << PAGE_SHIFT; +#ifdef CONFIG_HUGETLB_PAGE + *pageshift = is_vm_hugetlb_page(vma) ? HPAGE_SHIFT : PAGE_SHIFT; +#else + *pageshift = PAGE_SHIFT; +#endif + return 0; + +err: + return 1; +} + +static int gru_vtop(struct gru_thread_state *gts, unsigned long vaddr, + int write, int atomic, unsigned long *gpa, int *pageshift) +{ + struct mm_struct *mm = gts->ts_mm; + struct vm_area_struct *vma; + unsigned long paddr; + int ret, ps; + + vma = find_vma(mm, vaddr); + if (!vma) + goto inval; + + /* + * Atomic lookup is faster & usually works even if called in non-atomic + * context. + */ + rmb(); /* Must/check ms_range_active before loading PTEs */ + ret = atomic_pte_lookup(vma, vaddr, write, &paddr, &ps); + if (ret) { + if (atomic) + goto upm; + if (non_atomic_pte_lookup(vma, vaddr, write, &paddr, &ps)) + goto inval; + } + if (is_gru_paddr(paddr)) + goto inval; + paddr = paddr & ~((1UL << ps) - 1); + *gpa = uv_soc_phys_ram_to_gpa(paddr); + *pageshift = ps; + return VTOP_SUCCESS; + +inval: + return VTOP_INVALID; +upm: + return VTOP_RETRY; +} + + +/* + * Flush a CBE from cache. The CBE is clean in the cache. Dirty the + * CBE cacheline so that the line will be written back to home agent. + * Otherwise the line may be silently dropped. This has no impact + * except on performance. + */ +static void gru_flush_cache_cbe(struct gru_control_block_extended *cbe) +{ + if (unlikely(cbe)) { + cbe->cbrexecstatus = 0; /* make CL dirty */ + gru_flush_cache(cbe); + } +} + +/* + * Preload the TLB with entries that may be required. Currently, preloading + * is implemented only for BCOPY. Preload <tlb_preload_count> pages OR to + * the end of the bcopy tranfer, whichever is smaller. + */ +static void gru_preload_tlb(struct gru_state *gru, + struct gru_thread_state *gts, int atomic, + unsigned long fault_vaddr, int asid, int write, + unsigned char tlb_preload_count, + struct gru_tlb_fault_handle *tfh, + struct gru_control_block_extended *cbe) +{ + unsigned long vaddr = 0, gpa; + int ret, pageshift; + + if (cbe->opccpy != OP_BCOPY) + return; + + if (fault_vaddr == cbe->cbe_baddr0) + vaddr = fault_vaddr + GRU_CACHE_LINE_BYTES * cbe->cbe_src_cl - 1; + else if (fault_vaddr == cbe->cbe_baddr1) + vaddr = fault_vaddr + (1 << cbe->xtypecpy) * cbe->cbe_nelemcur - 1; + + fault_vaddr &= PAGE_MASK; + vaddr &= PAGE_MASK; + vaddr = min(vaddr, fault_vaddr + tlb_preload_count * PAGE_SIZE); + + while (vaddr > fault_vaddr) { + ret = gru_vtop(gts, vaddr, write, atomic, &gpa, &pageshift); + if (ret || tfh_write_only(tfh, gpa, GAA_RAM, vaddr, asid, write, + GRU_PAGESIZE(pageshift))) + return; + gru_dbg(grudev, + "%s: gid %d, gts 0x%p, tfh 0x%p, vaddr 0x%lx, asid 0x%x, rw %d, ps %d, gpa 0x%lx\n", + atomic ? "atomic" : "non-atomic", gru->gs_gid, gts, tfh, + vaddr, asid, write, pageshift, gpa); + vaddr -= PAGE_SIZE; + STAT(tlb_preload_page); + } +} + +/* + * Drop a TLB entry into the GRU. The fault is described by info in an TFH. + * Input: + * cb Address of user CBR. Null if not running in user context + * Return: + * 0 = dropin, exception, or switch to UPM successful + * 1 = range invalidate active + * < 0 = error code + * + */ +static int gru_try_dropin(struct gru_state *gru, + struct gru_thread_state *gts, + struct gru_tlb_fault_handle *tfh, + struct gru_instruction_bits *cbk) +{ + struct gru_control_block_extended *cbe = NULL; + unsigned char tlb_preload_count = gts->ts_tlb_preload_count; + int pageshift = 0, asid, write, ret, atomic = !cbk, indexway; + unsigned long gpa = 0, vaddr = 0; + + /* + * NOTE: The GRU contains magic hardware that eliminates races between + * TLB invalidates and TLB dropins. If an invalidate occurs + * in the window between reading the TFH and the subsequent TLB dropin, + * the dropin is ignored. This eliminates the need for additional locks. + */ + + /* + * Prefetch the CBE if doing TLB preloading + */ + if (unlikely(tlb_preload_count)) { + cbe = gru_tfh_to_cbe(tfh); + prefetchw(cbe); + } + + /* + * Error if TFH state is IDLE or FMM mode & the user issuing a UPM call. + * Might be a hardware race OR a stupid user. Ignore FMM because FMM + * is a transient state. + */ + if (tfh->status != TFHSTATUS_EXCEPTION) { + gru_flush_cache(tfh); + sync_core(); + if (tfh->status != TFHSTATUS_EXCEPTION) + goto failnoexception; + STAT(tfh_stale_on_fault); + } + if (tfh->state == TFHSTATE_IDLE) + goto failidle; + if (tfh->state == TFHSTATE_MISS_FMM && cbk) + goto failfmm; + + write = (tfh->cause & TFHCAUSE_TLB_MOD) != 0; + vaddr = tfh->missvaddr; + asid = tfh->missasid; + indexway = tfh->indexway; + if (asid == 0) + goto failnoasid; + + rmb(); /* TFH must be cache resident before reading ms_range_active */ + + /* + * TFH is cache resident - at least briefly. Fail the dropin + * if a range invalidate is active. + */ + if (atomic_read(>s->ts_gms->ms_range_active)) + goto failactive; + + ret = gru_vtop(gts, vaddr, write, atomic, &gpa, &pageshift); + if (ret == VTOP_INVALID) + goto failinval; + if (ret == VTOP_RETRY) + goto failupm; + + if (!(gts->ts_sizeavail & GRU_SIZEAVAIL(pageshift))) { + gts->ts_sizeavail |= GRU_SIZEAVAIL(pageshift); + if (atomic || !gru_update_cch(gts)) { + gts->ts_force_cch_reload = 1; + goto failupm; + } + } + + if (unlikely(cbe) && pageshift == PAGE_SHIFT) { + gru_preload_tlb(gru, gts, atomic, vaddr, asid, write, tlb_preload_count, tfh, cbe); + gru_flush_cache_cbe(cbe); + } + + gru_cb_set_istatus_active(cbk); + gts->ustats.tlbdropin++; + tfh_write_restart(tfh, gpa, GAA_RAM, vaddr, asid, write, + GRU_PAGESIZE(pageshift)); + gru_dbg(grudev, + "%s: gid %d, gts 0x%p, tfh 0x%p, vaddr 0x%lx, asid 0x%x, indexway 0x%x," + " rw %d, ps %d, gpa 0x%lx\n", + atomic ? "atomic" : "non-atomic", gru->gs_gid, gts, tfh, vaddr, asid, + indexway, write, pageshift, gpa); + STAT(tlb_dropin); + return 0; + +failnoasid: + /* No asid (delayed unload). */ + STAT(tlb_dropin_fail_no_asid); + gru_dbg(grudev, "FAILED no_asid tfh: 0x%p, vaddr 0x%lx\n", tfh, vaddr); + if (!cbk) + tfh_user_polling_mode(tfh); + else + gru_flush_cache(tfh); + gru_flush_cache_cbe(cbe); + return -EAGAIN; + +failupm: + /* Atomic failure switch CBR to UPM */ + tfh_user_polling_mode(tfh); + gru_flush_cache_cbe(cbe); + STAT(tlb_dropin_fail_upm); + gru_dbg(grudev, "FAILED upm tfh: 0x%p, vaddr 0x%lx\n", tfh, vaddr); + return 1; + +failfmm: + /* FMM state on UPM call */ + gru_flush_cache(tfh); + gru_flush_cache_cbe(cbe); + STAT(tlb_dropin_fail_fmm); + gru_dbg(grudev, "FAILED fmm tfh: 0x%p, state %d\n", tfh, tfh->state); + return 0; + +failnoexception: + /* TFH status did not show exception pending */ + gru_flush_cache(tfh); + gru_flush_cache_cbe(cbe); + if (cbk) + gru_flush_cache(cbk); + STAT(tlb_dropin_fail_no_exception); + gru_dbg(grudev, "FAILED non-exception tfh: 0x%p, status %d, state %d\n", + tfh, tfh->status, tfh->state); + return 0; + +failidle: + /* TFH state was idle - no miss pending */ + gru_flush_cache(tfh); + gru_flush_cache_cbe(cbe); + if (cbk) + gru_flush_cache(cbk); + STAT(tlb_dropin_fail_idle); + gru_dbg(grudev, "FAILED idle tfh: 0x%p, state %d\n", tfh, tfh->state); + return 0; + +failinval: + /* All errors (atomic & non-atomic) switch CBR to EXCEPTION state */ + tfh_exception(tfh); + gru_flush_cache_cbe(cbe); + STAT(tlb_dropin_fail_invalid); + gru_dbg(grudev, "FAILED inval tfh: 0x%p, vaddr 0x%lx\n", tfh, vaddr); + return -EFAULT; + +failactive: + /* Range invalidate active. Switch to UPM iff atomic */ + if (!cbk) + tfh_user_polling_mode(tfh); + else + gru_flush_cache(tfh); + gru_flush_cache_cbe(cbe); + STAT(tlb_dropin_fail_range_active); + gru_dbg(grudev, "FAILED range active: tfh 0x%p, vaddr 0x%lx\n", + tfh, vaddr); + return 1; +} + +/* + * Process an external interrupt from the GRU. This interrupt is + * caused by a TLB miss. + * Note that this is the interrupt handler that is registered with linux + * interrupt handlers. + */ +static irqreturn_t gru_intr(int chiplet, int blade) +{ + struct gru_state *gru; + struct gru_tlb_fault_map imap, dmap; + struct gru_thread_state *gts; + struct gru_tlb_fault_handle *tfh = NULL; + struct completion *cmp; + int cbrnum, ctxnum; + + STAT(intr); + + gru = &gru_base[blade]->bs_grus[chiplet]; + if (!gru) { + dev_err(grudev, "GRU: invalid interrupt: cpu %d, chiplet %d\n", + raw_smp_processor_id(), chiplet); + return IRQ_NONE; + } + get_clear_fault_map(gru, &imap, &dmap); + gru_dbg(grudev, + "cpu %d, chiplet %d, gid %d, imap %016lx %016lx, dmap %016lx %016lx\n", + smp_processor_id(), chiplet, gru->gs_gid, + imap.fault_bits[0], imap.fault_bits[1], + dmap.fault_bits[0], dmap.fault_bits[1]); + + for_each_cbr_in_tfm(cbrnum, dmap.fault_bits) { + STAT(intr_cbr); + cmp = gru->gs_blade->bs_async_wq; + if (cmp) + complete(cmp); + gru_dbg(grudev, "gid %d, cbr_done %d, done %d\n", + gru->gs_gid, cbrnum, cmp ? cmp->done : -1); + } + + for_each_cbr_in_tfm(cbrnum, imap.fault_bits) { + STAT(intr_tfh); + tfh = get_tfh_by_index(gru, cbrnum); + prefetchw(tfh); /* Helps on hdw, required for emulator */ + + /* + * When hardware sets a bit in the faultmap, it implicitly + * locks the GRU context so that it cannot be unloaded. + * The gts cannot change until a TFH start/writestart command + * is issued. + */ + ctxnum = tfh->ctxnum; + gts = gru->gs_gts[ctxnum]; + + /* Spurious interrupts can cause this. Ignore. */ + if (!gts) { + STAT(intr_spurious); + continue; + } + + /* + * This is running in interrupt context. Trylock the mmap_lock. + * If it fails, retry the fault in user context. + */ + gts->ustats.fmm_tlbmiss++; + if (!gts->ts_force_cch_reload && + mmap_read_trylock(gts->ts_mm)) { + gru_try_dropin(gru, gts, tfh, NULL); + mmap_read_unlock(gts->ts_mm); + } else { + tfh_user_polling_mode(tfh); + STAT(intr_mm_lock_failed); + } + } + return IRQ_HANDLED; +} + +irqreturn_t gru0_intr(int irq, void *dev_id) +{ + return gru_intr(0, uv_numa_blade_id()); +} + +irqreturn_t gru1_intr(int irq, void *dev_id) +{ + return gru_intr(1, uv_numa_blade_id()); +} + +irqreturn_t gru_intr_mblade(int irq, void *dev_id) +{ + int blade; + + for_each_possible_blade(blade) { + if (uv_blade_nr_possible_cpus(blade)) + continue; + gru_intr(0, blade); + gru_intr(1, blade); + } + return IRQ_HANDLED; +} + + +static int gru_user_dropin(struct gru_thread_state *gts, + struct gru_tlb_fault_handle *tfh, + void *cb) +{ + struct gru_mm_struct *gms = gts->ts_gms; + int ret; + + gts->ustats.upm_tlbmiss++; + while (1) { + wait_event(gms->ms_wait_queue, + atomic_read(&gms->ms_range_active) == 0); + prefetchw(tfh); /* Helps on hdw, required for emulator */ + ret = gru_try_dropin(gts->ts_gru, gts, tfh, cb); + if (ret <= 0) + return ret; + STAT(call_os_wait_queue); + } +} + +/* + * This interface is called as a result of a user detecting a "call OS" bit + * in a user CB. Normally means that a TLB fault has occurred. + * cb - user virtual address of the CB + */ +int gru_handle_user_call_os(unsigned long cb) +{ + struct gru_tlb_fault_handle *tfh; + struct gru_thread_state *gts; + void *cbk; + int ucbnum, cbrnum, ret = -EINVAL; + + STAT(call_os); + + /* sanity check the cb pointer */ + ucbnum = get_cb_number((void *)cb); + if ((cb & (GRU_HANDLE_STRIDE - 1)) || ucbnum >= GRU_NUM_CB) + return -EINVAL; + +again: + gts = gru_find_lock_gts(cb); + if (!gts) + return -EINVAL; + gru_dbg(grudev, "address 0x%lx, gid %d, gts 0x%p\n", cb, gts->ts_gru ? gts->ts_gru->gs_gid : -1, gts); + + if (ucbnum >= gts->ts_cbr_au_count * GRU_CBR_AU_SIZE) + goto exit; + + if (gru_check_context_placement(gts)) { + gru_unlock_gts(gts); + gru_unload_context(gts, 1); + goto again; + } + + /* + * CCH may contain stale data if ts_force_cch_reload is set. + */ + if (gts->ts_gru && gts->ts_force_cch_reload) { + gts->ts_force_cch_reload = 0; + gru_update_cch(gts); + } + + ret = -EAGAIN; + cbrnum = thread_cbr_number(gts, ucbnum); + if (gts->ts_gru) { + tfh = get_tfh_by_index(gts->ts_gru, cbrnum); + cbk = get_gseg_base_address_cb(gts->ts_gru->gs_gru_base_vaddr, + gts->ts_ctxnum, ucbnum); + ret = gru_user_dropin(gts, tfh, cbk); + } +exit: + gru_unlock_gts(gts); + return ret; +} + +/* + * Fetch the exception detail information for a CB that terminated with + * an exception. + */ +int gru_get_exception_detail(unsigned long arg) +{ + struct control_block_extended_exc_detail excdet; + struct gru_control_block_extended *cbe; + struct gru_thread_state *gts; + int ucbnum, cbrnum, ret; + + STAT(user_exception); + if (copy_from_user(&excdet, (void __user *)arg, sizeof(excdet))) + return -EFAULT; + + gts = gru_find_lock_gts(excdet.cb); + if (!gts) + return -EINVAL; + + gru_dbg(grudev, "address 0x%lx, gid %d, gts 0x%p\n", excdet.cb, gts->ts_gru ? gts->ts_gru->gs_gid : -1, gts); + ucbnum = get_cb_number((void *)excdet.cb); + if (ucbnum >= gts->ts_cbr_au_count * GRU_CBR_AU_SIZE) { + ret = -EINVAL; + } else if (gts->ts_gru) { + cbrnum = thread_cbr_number(gts, ucbnum); + cbe = get_cbe_by_index(gts->ts_gru, cbrnum); + gru_flush_cache(cbe); /* CBE not coherent */ + sync_core(); /* make sure we are have current data */ + excdet.opc = cbe->opccpy; + excdet.exopc = cbe->exopccpy; + excdet.ecause = cbe->ecause; + excdet.exceptdet0 = cbe->idef1upd; + excdet.exceptdet1 = cbe->idef3upd; + excdet.cbrstate = cbe->cbrstate; + excdet.cbrexecstatus = cbe->cbrexecstatus; + gru_flush_cache_cbe(cbe); + ret = 0; + } else { + ret = -EAGAIN; + } + gru_unlock_gts(gts); + + gru_dbg(grudev, + "cb 0x%lx, op %d, exopc %d, cbrstate %d, cbrexecstatus 0x%x, ecause 0x%x, " + "exdet0 0x%lx, exdet1 0x%x\n", + excdet.cb, excdet.opc, excdet.exopc, excdet.cbrstate, excdet.cbrexecstatus, + excdet.ecause, excdet.exceptdet0, excdet.exceptdet1); + if (!ret && copy_to_user((void __user *)arg, &excdet, sizeof(excdet))) + ret = -EFAULT; + return ret; +} + +/* + * User request to unload a context. Content is saved for possible reload. + */ +static int gru_unload_all_contexts(void) +{ + struct gru_thread_state *gts; + struct gru_state *gru; + int gid, ctxnum; + + if (!capable(CAP_SYS_ADMIN)) + return -EPERM; + foreach_gid(gid) { + gru = GID_TO_GRU(gid); + spin_lock(&gru->gs_lock); + for (ctxnum = 0; ctxnum < GRU_NUM_CCH; ctxnum++) { + gts = gru->gs_gts[ctxnum]; + if (gts && mutex_trylock(>s->ts_ctxlock)) { + spin_unlock(&gru->gs_lock); + gru_unload_context(gts, 1); + mutex_unlock(>s->ts_ctxlock); + spin_lock(&gru->gs_lock); + } + } + spin_unlock(&gru->gs_lock); + } + return 0; +} + +int gru_user_unload_context(unsigned long arg) +{ + struct gru_thread_state *gts; + struct gru_unload_context_req req; + + STAT(user_unload_context); + if (copy_from_user(&req, (void __user *)arg, sizeof(req))) + return -EFAULT; + + gru_dbg(grudev, "gseg 0x%lx\n", req.gseg); + + if (!req.gseg) + return gru_unload_all_contexts(); + + gts = gru_find_lock_gts(req.gseg); + if (!gts) + return -EINVAL; + + if (gts->ts_gru) + gru_unload_context(gts, 1); + gru_unlock_gts(gts); + + return 0; +} + +/* + * User request to flush a range of virtual addresses from the GRU TLB + * (Mainly for testing). + */ +int gru_user_flush_tlb(unsigned long arg) +{ + struct gru_thread_state *gts; + struct gru_flush_tlb_req req; + struct gru_mm_struct *gms; + + STAT(user_flush_tlb); + if (copy_from_user(&req, (void __user *)arg, sizeof(req))) + return -EFAULT; + + gru_dbg(grudev, "gseg 0x%lx, vaddr 0x%lx, len 0x%lx\n", req.gseg, + req.vaddr, req.len); + + gts = gru_find_lock_gts(req.gseg); + if (!gts) + return -EINVAL; + + gms = gts->ts_gms; + gru_unlock_gts(gts); + gru_flush_tlb_range(gms, req.vaddr, req.len); + + return 0; +} + +/* + * Fetch GSEG statisticss + */ +long gru_get_gseg_statistics(unsigned long arg) +{ + struct gru_thread_state *gts; + struct gru_get_gseg_statistics_req req; + + if (copy_from_user(&req, (void __user *)arg, sizeof(req))) + return -EFAULT; + + /* + * The library creates arrays of contexts for threaded programs. + * If no gts exists in the array, the context has never been used & all + * statistics are implicitly 0. + */ + gts = gru_find_lock_gts(req.gseg); + if (gts) { + memcpy(&req.stats, >s->ustats, sizeof(gts->ustats)); + gru_unlock_gts(gts); + } else { + memset(&req.stats, 0, sizeof(gts->ustats)); + } + + if (copy_to_user((void __user *)arg, &req, sizeof(req))) + return -EFAULT; + + return 0; +} + +/* + * Register the current task as the user of the GSEG slice. + * Needed for TLB fault interrupt targeting. + */ +int gru_set_context_option(unsigned long arg) +{ + struct gru_thread_state *gts; + struct gru_set_context_option_req req; + int ret = 0; + + STAT(set_context_option); + if (copy_from_user(&req, (void __user *)arg, sizeof(req))) + return -EFAULT; + gru_dbg(grudev, "op %d, gseg 0x%lx, value1 0x%lx\n", req.op, req.gseg, req.val1); + + gts = gru_find_lock_gts(req.gseg); + if (!gts) { + gts = gru_alloc_locked_gts(req.gseg); + if (IS_ERR(gts)) + return PTR_ERR(gts); + } + + switch (req.op) { + case sco_blade_chiplet: + /* Select blade/chiplet for GRU context */ + if (req.val0 < -1 || req.val0 >= GRU_CHIPLETS_PER_HUB || + req.val1 < -1 || req.val1 >= GRU_MAX_BLADES || + (req.val1 >= 0 && !gru_base[req.val1])) { + ret = -EINVAL; + } else { + gts->ts_user_blade_id = req.val1; + gts->ts_user_chiplet_id = req.val0; + if (gru_check_context_placement(gts)) { + gru_unlock_gts(gts); + gru_unload_context(gts, 1); + return ret; + } + } + break; + case sco_gseg_owner: + /* Register the current task as the GSEG owner */ + gts->ts_tgid_owner = current->tgid; + break; + case sco_cch_req_slice: + /* Set the CCH slice option */ + gts->ts_cch_req_slice = req.val1 & 3; + break; + default: + ret = -EINVAL; + } + gru_unlock_gts(gts); + + return ret; +} |