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Diffstat (limited to 'drivers/misc/cxl/context.c')
-rw-r--r--drivers/misc/cxl/context.c362
1 files changed, 0 insertions, 362 deletions
diff --git a/drivers/misc/cxl/context.c b/drivers/misc/cxl/context.c
deleted file mode 100644
index 76b5ea66dfa1..000000000000
--- a/drivers/misc/cxl/context.c
+++ /dev/null
@@ -1,362 +0,0 @@
-// SPDX-License-Identifier: GPL-2.0-or-later
-/*
- * Copyright 2014 IBM Corp.
- */
-
-#include <linux/module.h>
-#include <linux/kernel.h>
-#include <linux/bitmap.h>
-#include <linux/sched.h>
-#include <linux/pid.h>
-#include <linux/fs.h>
-#include <linux/mm.h>
-#include <linux/debugfs.h>
-#include <linux/slab.h>
-#include <linux/idr.h>
-#include <linux/sched/mm.h>
-#include <linux/mmu_context.h>
-#include <asm/cputable.h>
-#include <asm/current.h>
-#include <asm/copro.h>
-
-#include "cxl.h"
-
-/*
- * Allocates space for a CXL context.
- */
-struct cxl_context *cxl_context_alloc(void)
-{
- return kzalloc(sizeof(struct cxl_context), GFP_KERNEL);
-}
-
-/*
- * Initialises a CXL context.
- */
-int cxl_context_init(struct cxl_context *ctx, struct cxl_afu *afu, bool master)
-{
- int i;
-
- ctx->afu = afu;
- ctx->master = master;
- ctx->pid = NULL; /* Set in start work ioctl */
- mutex_init(&ctx->mapping_lock);
- ctx->mapping = NULL;
- ctx->tidr = 0;
- ctx->assign_tidr = false;
-
- if (cxl_is_power8()) {
- spin_lock_init(&ctx->sste_lock);
-
- /*
- * Allocate the segment table before we put it in the IDR so that we
- * can always access it when dereferenced from IDR. For the same
- * reason, the segment table is only destroyed after the context is
- * removed from the IDR. Access to this in the IOCTL is protected by
- * Linux filesystem semantics (can't IOCTL until open is complete).
- */
- i = cxl_alloc_sst(ctx);
- if (i)
- return i;
- }
-
- INIT_WORK(&ctx->fault_work, cxl_handle_fault);
-
- init_waitqueue_head(&ctx->wq);
- spin_lock_init(&ctx->lock);
-
- ctx->irq_bitmap = NULL;
- ctx->pending_irq = false;
- ctx->pending_fault = false;
- ctx->pending_afu_err = false;
-
- INIT_LIST_HEAD(&ctx->irq_names);
-
- /*
- * When we have to destroy all contexts in cxl_context_detach_all() we
- * end up with afu_release_irqs() called from inside a
- * idr_for_each_entry(). Hence we need to make sure that anything
- * dereferenced from this IDR is ok before we allocate the IDR here.
- * This clears out the IRQ ranges to ensure this.
- */
- for (i = 0; i < CXL_IRQ_RANGES; i++)
- ctx->irqs.range[i] = 0;
-
- mutex_init(&ctx->status_mutex);
-
- ctx->status = OPENED;
-
- /*
- * Allocating IDR! We better make sure everything's setup that
- * dereferences from it.
- */
- mutex_lock(&afu->contexts_lock);
- idr_preload(GFP_KERNEL);
- i = idr_alloc(&ctx->afu->contexts_idr, ctx, 0,
- ctx->afu->num_procs, GFP_NOWAIT);
- idr_preload_end();
- mutex_unlock(&afu->contexts_lock);
- if (i < 0)
- return i;
-
- ctx->pe = i;
- if (cpu_has_feature(CPU_FTR_HVMODE)) {
- ctx->elem = &ctx->afu->native->spa[i];
- ctx->external_pe = ctx->pe;
- } else {
- ctx->external_pe = -1; /* assigned when attaching */
- }
- ctx->pe_inserted = false;
-
- /*
- * take a ref on the afu so that it stays alive at-least till
- * this context is reclaimed inside reclaim_ctx.
- */
- cxl_afu_get(afu);
- return 0;
-}
-
-void cxl_context_set_mapping(struct cxl_context *ctx,
- struct address_space *mapping)
-{
- mutex_lock(&ctx->mapping_lock);
- ctx->mapping = mapping;
- mutex_unlock(&ctx->mapping_lock);
-}
-
-static vm_fault_t cxl_mmap_fault(struct vm_fault *vmf)
-{
- struct vm_area_struct *vma = vmf->vma;
- struct cxl_context *ctx = vma->vm_file->private_data;
- u64 area, offset;
- vm_fault_t ret;
-
- offset = vmf->pgoff << PAGE_SHIFT;
-
- pr_devel("%s: pe: %i address: 0x%lx offset: 0x%llx\n",
- __func__, ctx->pe, vmf->address, offset);
-
- if (ctx->afu->current_mode == CXL_MODE_DEDICATED) {
- area = ctx->afu->psn_phys;
- if (offset >= ctx->afu->adapter->ps_size)
- return VM_FAULT_SIGBUS;
- } else {
- area = ctx->psn_phys;
- if (offset >= ctx->psn_size)
- return VM_FAULT_SIGBUS;
- }
-
- mutex_lock(&ctx->status_mutex);
-
- if (ctx->status != STARTED) {
- mutex_unlock(&ctx->status_mutex);
- pr_devel("%s: Context not started, failing problem state access\n", __func__);
- if (ctx->mmio_err_ff) {
- if (!ctx->ff_page) {
- ctx->ff_page = alloc_page(GFP_USER);
- if (!ctx->ff_page)
- return VM_FAULT_OOM;
- memset(page_address(ctx->ff_page), 0xff, PAGE_SIZE);
- }
- get_page(ctx->ff_page);
- vmf->page = ctx->ff_page;
- vma->vm_page_prot = pgprot_cached(vma->vm_page_prot);
- return 0;
- }
- return VM_FAULT_SIGBUS;
- }
-
- ret = vmf_insert_pfn(vma, vmf->address, (area + offset) >> PAGE_SHIFT);
-
- mutex_unlock(&ctx->status_mutex);
-
- return ret;
-}
-
-static const struct vm_operations_struct cxl_mmap_vmops = {
- .fault = cxl_mmap_fault,
-};
-
-/*
- * Map a per-context mmio space into the given vma.
- */
-int cxl_context_iomap(struct cxl_context *ctx, struct vm_area_struct *vma)
-{
- u64 start = vma->vm_pgoff << PAGE_SHIFT;
- u64 len = vma->vm_end - vma->vm_start;
-
- if (ctx->afu->current_mode == CXL_MODE_DEDICATED) {
- if (start + len > ctx->afu->adapter->ps_size)
- return -EINVAL;
-
- if (cxl_is_power9()) {
- /*
- * Make sure there is a valid problem state
- * area space for this AFU.
- */
- if (ctx->master && !ctx->afu->psa) {
- pr_devel("AFU doesn't support mmio space\n");
- return -EINVAL;
- }
-
- /* Can't mmap until the AFU is enabled */
- if (!ctx->afu->enabled)
- return -EBUSY;
- }
- } else {
- if (start + len > ctx->psn_size)
- return -EINVAL;
-
- /* Make sure there is a valid per process space for this AFU */
- if ((ctx->master && !ctx->afu->psa) || (!ctx->afu->pp_psa)) {
- pr_devel("AFU doesn't support mmio space\n");
- return -EINVAL;
- }
-
- /* Can't mmap until the AFU is enabled */
- if (!ctx->afu->enabled)
- return -EBUSY;
- }
-
- pr_devel("%s: mmio physical: %llx pe: %i master:%i\n", __func__,
- ctx->psn_phys, ctx->pe , ctx->master);
-
- vm_flags_set(vma, VM_IO | VM_PFNMAP);
- vma->vm_page_prot = pgprot_noncached(vma->vm_page_prot);
- vma->vm_ops = &cxl_mmap_vmops;
- return 0;
-}
-
-/*
- * Detach a context from the hardware. This disables interrupts and doesn't
- * return until all outstanding interrupts for this context have completed. The
- * hardware should no longer access *ctx after this has returned.
- */
-int __detach_context(struct cxl_context *ctx)
-{
- enum cxl_context_status status;
-
- mutex_lock(&ctx->status_mutex);
- status = ctx->status;
- ctx->status = CLOSED;
- mutex_unlock(&ctx->status_mutex);
- if (status != STARTED)
- return -EBUSY;
-
- /* Only warn if we detached while the link was OK.
- * If detach fails when hw is down, we don't care.
- */
- WARN_ON(cxl_ops->detach_process(ctx) &&
- cxl_ops->link_ok(ctx->afu->adapter, ctx->afu));
- flush_work(&ctx->fault_work); /* Only needed for dedicated process */
-
- /*
- * Wait until no further interrupts are presented by the PSL
- * for this context.
- */
- if (cxl_ops->irq_wait)
- cxl_ops->irq_wait(ctx);
-
- /* release the reference to the group leader and mm handling pid */
- put_pid(ctx->pid);
-
- cxl_ctx_put();
-
- /* Decrease the attached context count on the adapter */
- cxl_adapter_context_put(ctx->afu->adapter);
-
- /* Decrease the mm count on the context */
- cxl_context_mm_count_put(ctx);
- if (ctx->mm)
- mm_context_remove_copro(ctx->mm);
- ctx->mm = NULL;
-
- return 0;
-}
-
-/*
- * Detach the given context from the AFU. This doesn't actually
- * free the context but it should stop the context running in hardware
- * (ie. prevent this context from generating any further interrupts
- * so that it can be freed).
- */
-void cxl_context_detach(struct cxl_context *ctx)
-{
- int rc;
-
- rc = __detach_context(ctx);
- if (rc)
- return;
-
- afu_release_irqs(ctx, ctx);
- wake_up_all(&ctx->wq);
-}
-
-/*
- * Detach all contexts on the given AFU.
- */
-void cxl_context_detach_all(struct cxl_afu *afu)
-{
- struct cxl_context *ctx;
- int tmp;
-
- mutex_lock(&afu->contexts_lock);
- idr_for_each_entry(&afu->contexts_idr, ctx, tmp) {
- /*
- * Anything done in here needs to be setup before the IDR is
- * created and torn down after the IDR removed
- */
- cxl_context_detach(ctx);
-
- /*
- * We are force detaching - remove any active PSA mappings so
- * userspace cannot interfere with the card if it comes back.
- * Easiest way to exercise this is to unbind and rebind the
- * driver via sysfs while it is in use.
- */
- mutex_lock(&ctx->mapping_lock);
- if (ctx->mapping)
- unmap_mapping_range(ctx->mapping, 0, 0, 1);
- mutex_unlock(&ctx->mapping_lock);
- }
- mutex_unlock(&afu->contexts_lock);
-}
-
-static void reclaim_ctx(struct rcu_head *rcu)
-{
- struct cxl_context *ctx = container_of(rcu, struct cxl_context, rcu);
-
- if (cxl_is_power8())
- free_page((u64)ctx->sstp);
- if (ctx->ff_page)
- __free_page(ctx->ff_page);
- ctx->sstp = NULL;
-
- bitmap_free(ctx->irq_bitmap);
-
- /* Drop ref to the afu device taken during cxl_context_init */
- cxl_afu_put(ctx->afu);
-
- kfree(ctx);
-}
-
-void cxl_context_free(struct cxl_context *ctx)
-{
- if (ctx->kernelapi && ctx->mapping)
- cxl_release_mapping(ctx);
- mutex_lock(&ctx->afu->contexts_lock);
- idr_remove(&ctx->afu->contexts_idr, ctx->pe);
- mutex_unlock(&ctx->afu->contexts_lock);
- call_rcu(&ctx->rcu, reclaim_ctx);
-}
-
-void cxl_context_mm_count_get(struct cxl_context *ctx)
-{
- if (ctx->mm)
- mmgrab(ctx->mm);
-}
-
-void cxl_context_mm_count_put(struct cxl_context *ctx)
-{
- if (ctx->mm)
- mmdrop(ctx->mm);
-}