1 // SPDX-License-Identifier: GPL-2.0-or-later
3  * VAS user space API for its accelerators (Only NX-GZIP is supported now)
7 #define pr_fmt(fmt)	"vas-api: " fmt
20 #include <uapi/asm/vas-api.h>
24  * For NX-GZIP
26  *	fd = open("/dev/crypto/nx-gzip", O_RDWR);
33  * where "vas_copy" and "vas_paste" are defined in copy-paste.h.
40  * Wrapper object for the nx-gzip device - there is just one instance of
73 	 * pid will not be re-used - needed only for multithread  in get_vas_user_win_ref()
76 	task_ref->pid = get_task_pid(current, PIDTYPE_PID);  in get_vas_user_win_ref()
80 	task_ref->mm = get_task_mm(current);  in get_vas_user_win_ref()
81 	if (!task_ref->mm) {  in get_vas_user_win_ref()
82 		put_pid(task_ref->pid);  in get_vas_user_win_ref()
84 				current->pid);  in get_vas_user_win_ref()
85 		return -EPERM;  in get_vas_user_win_ref()
88 	mmgrab(task_ref->mm);  in get_vas_user_win_ref()
89 	mmput(task_ref->mm);  in get_vas_user_win_ref()
97 	task_ref->tgid = find_get_pid(task_tgid_vnr(current));  in get_vas_user_win_ref()
112 	pid = task_ref->pid;  in ref_get_pid_and_task()
115 		pid = task_ref->tgid;  in ref_get_pid_and_task()
126 	if (tsk->flags & PF_EXITING) {  in ref_get_pid_and_task()
146  * invalid csb_addr, send a signal to the process.
159 	 * NX user space windows can not be opened for task->mm=NULL  in vas_update_csb()
162 	if (WARN_ON_ONCE(!task_ref->mm))  in vas_update_csb()
165 	csb_addr = (void __user *)be64_to_cpu(crb->csb_addr);  in vas_update_csb()
178 	csb.address = crb->stamp.nx.fault_storage_addr;  in vas_update_csb()
182 	 * Process closes send window after all pending NX requests are  in vas_update_csb()
183 	 * completed. In multi-thread applications, a child thread can  in vas_update_csb()
189 	 * invalid, send SEGV signal to pid saved in window. If the  in vas_update_csb()
190 	 * child thread is not running, send the signal to tgid.  in vas_update_csb()
201 	kthread_use_mm(task_ref->mm);  in vas_update_csb()
213 	kthread_unuse_mm(task_ref->mm);  in vas_update_csb()
248 	dde = &crb->source;  in vas_dump_crb()
250 		be64_to_cpu(dde->address), be32_to_cpu(dde->length),  in vas_dump_crb()
251 		dde->count, dde->index, dde->flags);  in vas_dump_crb()
253 	dde = &crb->target;  in vas_dump_crb()
255 		be64_to_cpu(dde->address), be32_to_cpu(dde->length),  in vas_dump_crb()
256 		dde->count, dde->index, dde->flags);  in vas_dump_crb()
258 	nx = &crb->stamp.nx;  in vas_dump_crb()
260 		be32_to_cpu(nx->pswid),  in vas_dump_crb()
261 		be64_to_cpu(crb->stamp.nx.fault_storage_addr),  in vas_dump_crb()
262 		nx->flags, nx->fault_status);  in vas_dump_crb()
271 		return -ENOMEM;  in coproc_open()
273 	cp_inst->coproc = container_of(inode->i_cdev, struct coproc_dev,  in coproc_open()
275 	fp->private_data = cp_inst;  in coproc_open()
288 	cp_inst = fp->private_data;  in coproc_ioc_tx_win_open()
293 	if (cp_inst->txwin)  in coproc_ioc_tx_win_open()
294 		return -EEXIST;  in coproc_ioc_tx_win_open()
299 		return -EFAULT;  in coproc_ioc_tx_win_open()
304 		return -EINVAL;  in coproc_ioc_tx_win_open()
307 	if (!cp_inst->coproc->vops || !cp_inst->coproc->vops->open_win) {  in coproc_ioc_tx_win_open()
309 		return -EACCES;  in coproc_ioc_tx_win_open()
312 	txwin = cp_inst->coproc->vops->open_win(uattr.vas_id, uattr.flags,  in coproc_ioc_tx_win_open()
313 						cp_inst->coproc->cop_type);  in coproc_ioc_tx_win_open()
320 	mutex_init(&txwin->task_ref.mmap_mutex);  in coproc_ioc_tx_win_open()
321 	cp_inst->txwin = txwin;  in coproc_ioc_tx_win_open()
328 	struct coproc_instance *cp_inst = fp->private_data;  in coproc_release()
331 	if (cp_inst->txwin) {  in coproc_release()
332 		if (cp_inst->coproc->vops &&  in coproc_release()
333 			cp_inst->coproc->vops->close_win) {  in coproc_release()
334 			rc = cp_inst->coproc->vops->close_win(cp_inst->txwin);  in coproc_release()
338 		cp_inst->txwin = NULL;  in coproc_release()
342 	fp->private_data = NULL;  in coproc_release()
361 	struct pt_regs *regs = current->thread.regs;  in do_fail_paste()
365 		return -EINVAL;  in do_fail_paste()
368 		return -EINVAL;  in do_fail_paste()
375 	if (get_user(instword, (u32 __user *)(regs->nip)))  in do_fail_paste()
376 		return -EAGAIN;  in do_fail_paste()
382 		return -ENOENT;  in do_fail_paste()
384 	regs->ccr &= ~0xe0000000;	/* Clear CR0[0-2] to fail paste */  in do_fail_paste()
397 	struct vm_area_struct *vma = vmf->vma;  in vas_mmap_fault()
398 	struct file *fp = vma->vm_file;  in vas_mmap_fault()
399 	struct coproc_instance *cp_inst = fp->private_data;  in vas_mmap_fault()
408 	if (!cp_inst || !cp_inst->txwin) {  in vas_mmap_fault()
413 	txwin = cp_inst->txwin;  in vas_mmap_fault()
416 	 * migration, invalidate the existing mapping for the current  in vas_mmap_fault()
417 	 * paste addresses and set windows in-active (zap_vma_pages in  in vas_mmap_fault()
419 	 * New mapping will be done later after migration or new credits  in vas_mmap_fault()
423 	if (txwin->task_ref.vma != vmf->vma) {  in vas_mmap_fault()
428 	mutex_lock(&txwin->task_ref.mmap_mutex);  in vas_mmap_fault()
435 	if (txwin->status == VAS_WIN_ACTIVE) {  in vas_mmap_fault()
436 		paste_addr = cp_inst->coproc->vops->paste_addr(txwin);  in vas_mmap_fault()
438 			fault = vmf_insert_pfn(vma, vma->vm_start,  in vas_mmap_fault()
440 			mutex_unlock(&txwin->task_ref.mmap_mutex);  in vas_mmap_fault()
444 	mutex_unlock(&txwin->task_ref.mmap_mutex);  in vas_mmap_fault()
448 	 * It can happen during migration or lost credits.  in vas_mmap_fault()
455 	 * for migration) or should fallback to SW compression or  in vas_mmap_fault()
458 	 * failures are coming during migration or core removal:  in vas_mmap_fault()
461 	if (!ret || (ret == -EAGAIN))  in vas_mmap_fault()
469  * struct which is used to unmap during migration if the window is
477 	struct file *fp = vma->vm_file;  in vas_mmap_close()
478 	struct coproc_instance *cp_inst = fp->private_data;  in vas_mmap_close()
482 	if (!cp_inst || !cp_inst->txwin) {  in vas_mmap_close()
487 	txwin = cp_inst->txwin;  in vas_mmap_close()
492 	if (WARN_ON(txwin->task_ref.vma != vma)) {  in vas_mmap_close()
497 	mutex_lock(&txwin->task_ref.mmap_mutex);  in vas_mmap_close()
498 	txwin->task_ref.vma = NULL;  in vas_mmap_close()
499 	mutex_unlock(&txwin->task_ref.mmap_mutex);  in vas_mmap_close()
509 	struct coproc_instance *cp_inst = fp->private_data;  in coproc_mmap()
516 	txwin = cp_inst->txwin;  in coproc_mmap()
518 	if ((vma->vm_end - vma->vm_start) > PAGE_SIZE) {  in coproc_mmap()
520 				(vma->vm_end - vma->vm_start), PAGE_SIZE);  in coproc_mmap()
521 		return -EINVAL;  in coproc_mmap()
524 	/* Ensure instance has an open send window */  in coproc_mmap()
526 		pr_err("No send window open?\n");  in coproc_mmap()
527 		return -EINVAL;  in coproc_mmap()
530 	if (!cp_inst->coproc->vops || !cp_inst->coproc->vops->paste_addr) {  in coproc_mmap()
532 		return -EACCES;  in coproc_mmap()
540 	 * -EACCES and expects the user space reissue mmap() when it  in coproc_mmap()
546 	mutex_lock(&txwin->task_ref.mmap_mutex);  in coproc_mmap()
547 	if (txwin->status != VAS_WIN_ACTIVE) {  in coproc_mmap()
549 		rc = -EACCES;  in coproc_mmap()
553 	paste_addr = cp_inst->coproc->vops->paste_addr(txwin);  in coproc_mmap()
556 		rc = -EINVAL;  in coproc_mmap()
564 	vma->vm_page_prot = pgprot_cached(vma->vm_page_prot);  in coproc_mmap()
566 	prot = __pgprot(pgprot_val(vma->vm_page_prot) | _PAGE_DIRTY);  in coproc_mmap()
568 	rc = remap_pfn_range(vma, vma->vm_start, pfn + vma->vm_pgoff,  in coproc_mmap()
569 			vma->vm_end - vma->vm_start, prot);  in coproc_mmap()
572 			vma->vm_start, rc);  in coproc_mmap()
574 	txwin->task_ref.vma = vma;  in coproc_mmap()
575 	vma->vm_ops = &vas_vm_ops;  in coproc_mmap()
578 	mutex_unlock(&txwin->task_ref.mmap_mutex);  in coproc_mmap()
588 		return -EINVAL;  in coproc_ioctl()
600  * Supporting only nx-gzip coprocessor type now, but this API code
607 	int rc = -EINVAL;  in vas_register_coproc_api()
625 	coproc_device.class->devnode = coproc_devnode;  in vas_register_coproc_api()
643 		pr_err("Unable to create coproc-%d %d\n", MINOR(devno), rc);  in vas_register_coproc_api()