diff --git a/drivers/misc/cxl/context.c b/drivers/misc/cxl/context.c index 51fd6b524371..d1b55fe62817 100644 --- a/drivers/misc/cxl/context.c +++ b/drivers/misc/cxl/context.c @@ -100,6 +100,46 @@ int cxl_context_init(struct cxl_context *ctx, struct cxl_afu *afu, bool master, return 0; } +static int cxl_mmap_fault(struct vm_area_struct *vma, struct vm_fault *vmf) +{ + struct cxl_context *ctx = vma->vm_file->private_data; + unsigned long address = (unsigned long)vmf->virtual_address; + u64 area, offset; + + offset = vmf->pgoff << PAGE_SHIFT; + + pr_devel("%s: pe: %i address: 0x%lx offset: 0x%llx\n", + __func__, ctx->pe, 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__); + return VM_FAULT_SIGBUS; + } + + vm_insert_pfn(vma, address, (area + offset) >> PAGE_SHIFT); + + mutex_unlock(&ctx->status_mutex); + + return VM_FAULT_NOPAGE; +} + +static const struct vm_operations_struct cxl_mmap_vmops = { + .fault = cxl_mmap_fault, +}; + /* * Map a per-context mmio space into the given vma. */ @@ -108,26 +148,25 @@ int cxl_context_iomap(struct cxl_context *ctx, struct vm_area_struct *vma) u64 len = vma->vm_end - vma->vm_start; len = min(len, ctx->psn_size); - if (ctx->afu->current_mode == CXL_MODE_DEDICATED) { - vma->vm_page_prot = pgprot_noncached(vma->vm_page_prot); - return vm_iomap_memory(vma, ctx->afu->psn_phys, ctx->afu->adapter->ps_size); - } + if (ctx->afu->current_mode != CXL_MODE_DEDICATED) { + /* 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; + } - /* 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; } - /* 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); + vma->vm_flags |= VM_IO | VM_PFNMAP; vma->vm_page_prot = pgprot_noncached(vma->vm_page_prot); - return vm_iomap_memory(vma, ctx->psn_phys, len); + vma->vm_ops = &cxl_mmap_vmops; + return 0; } /* @@ -150,12 +189,6 @@ static void __detach_context(struct cxl_context *ctx) afu_release_irqs(ctx); flush_work(&ctx->fault_work); /* Only needed for dedicated process */ wake_up_all(&ctx->wq); - - /* Release Problem State Area mapping */ - mutex_lock(&ctx->mapping_lock); - if (ctx->mapping) - unmap_mapping_range(ctx->mapping, 0, 0, 1); - mutex_unlock(&ctx->mapping_lock); } /* @@ -184,6 +217,17 @@ void cxl_context_detach_all(struct cxl_afu *afu) * created and torn down after the IDR removed */ __detach_context(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); } diff --git a/drivers/misc/cxl/file.c b/drivers/misc/cxl/file.c index e9f2f10dbb37..b15d8113877c 100644 --- a/drivers/misc/cxl/file.c +++ b/drivers/misc/cxl/file.c @@ -140,18 +140,20 @@ static long afu_ioctl_start_work(struct cxl_context *ctx, pr_devel("%s: pe: %i\n", __func__, ctx->pe); - mutex_lock(&ctx->status_mutex); - if (ctx->status != OPENED) { - rc = -EIO; - goto out; - } - + /* Do this outside the status_mutex to avoid a circular dependency with + * the locking in cxl_mmap_fault() */ if (copy_from_user(&work, uwork, sizeof(struct cxl_ioctl_start_work))) { rc = -EFAULT; goto out; } + mutex_lock(&ctx->status_mutex); + if (ctx->status != OPENED) { + rc = -EIO; + goto out; + } + /* * if any of the reserved fields are set or any of the unused * flags are set it's invalid