diff options
Diffstat (limited to 'drivers/misc/cxl/context.c')
-rw-r--r-- | drivers/misc/cxl/context.c | 362 |
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); -} |