[deliverable/linux.git] / arch / powerpc / mm / copro_fault.c

/*
 * CoProcessor (SPU/AFU) mm fault handler
 *
 * (C) Copyright IBM Deutschland Entwicklung GmbH 2007
 *
 * Author: Arnd Bergmann <arndb@de.ibm.com>
 * Author: Jeremy Kerr <jk@ozlabs.org>
 *
 * This program is free software; you can redistribute it and/or modify
 * it under the terms of the GNU General Public License as published by
 * the Free Software Foundation; either version 2, or (at your option)
 * any later version.
 *
 * This program is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 * GNU General Public License for more details.
 *
 * You should have received a copy of the GNU General Public License
 * along with this program; if not, write to the Free Software
 * Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
 */
#include <linux/sched.h>
#include <linux/mm.h>
#include <linux/export.h>
#include <asm/reg.h>
#include <asm/copro.h>
#include <asm/spu.h>
#include <misc/cxl-base.h>

/*
 * This ought to be kept in sync with the powerpc specific do_page_fault
 * function. Currently, there are a few corner cases that we haven't had
 * to handle fortunately.
 */
int copro_handle_mm_fault(struct mm_struct *mm, unsigned long ea,
		unsigned long dsisr, unsigned *flt)
{
	struct vm_area_struct *vma;
	unsigned long is_write;
	int ret;

	if (mm == NULL)
		return -EFAULT;

	if (mm->pgd == NULL)
		return -EFAULT;

	down_read(&mm->mmap_sem);
	ret = -EFAULT;
	vma = find_vma(mm, ea);
	if (!vma)
		goto out_unlock;

	if (ea < vma->vm_start) {
		if (!(vma->vm_flags & VM_GROWSDOWN))
			goto out_unlock;
		if (expand_stack(vma, ea))
			goto out_unlock;
	}

	is_write = dsisr & DSISR_ISSTORE;
	if (is_write) {
		if (!(vma->vm_flags & VM_WRITE))
			goto out_unlock;
	} else {
		if (!(vma->vm_flags & (VM_READ | VM_EXEC)))
			goto out_unlock;
		/*
		 * protfault should only happen due to us
		 * mapping a region readonly temporarily. PROT_NONE
		 * is also covered by the VMA check above.
		 */
		WARN_ON_ONCE(dsisr & DSISR_PROTFAULT);
	}

	ret = 0;
	*flt = handle_mm_fault(mm, vma, ea, is_write ? FAULT_FLAG_WRITE : 0);
	if (unlikely(*flt & VM_FAULT_ERROR)) {
		if (*flt & VM_FAULT_OOM) {
			ret = -ENOMEM;
			goto out_unlock;
		} else if (*flt & (VM_FAULT_SIGBUS | VM_FAULT_SIGSEGV)) {
			ret = -EFAULT;
			goto out_unlock;
		}
		BUG();
	}

	if (*flt & VM_FAULT_MAJOR)
		current->maj_flt++;
	else
		current->min_flt++;

out_unlock:
	up_read(&mm->mmap_sem);
	return ret;
}
EXPORT_SYMBOL_GPL(copro_handle_mm_fault);

int copro_calculate_slb(struct mm_struct *mm, u64 ea, struct copro_slb *slb)
{
	u64 vsid, vsidkey;
	int psize, ssize;

	switch (REGION_ID(ea)) {
	case USER_REGION_ID:
		pr_devel("%s: 0x%llx -- USER_REGION_ID\n", __func__, ea);
		psize = get_slice_psize(mm, ea);
		ssize = user_segment_size(ea);
		vsid = get_vsid(mm->context.id, ea, ssize);
		vsidkey = SLB_VSID_USER;
		break;
	case VMALLOC_REGION_ID:
		pr_devel("%s: 0x%llx -- VMALLOC_REGION_ID\n", __func__, ea);
		if (ea < VMALLOC_END)
			psize = mmu_vmalloc_psize;
		else
			psize = mmu_io_psize;
		ssize = mmu_kernel_ssize;
		vsid = get_kernel_vsid(ea, mmu_kernel_ssize);
		vsidkey = SLB_VSID_KERNEL;
		break;
	case KERNEL_REGION_ID:
		pr_devel("%s: 0x%llx -- KERNEL_REGION_ID\n", __func__, ea);
		psize = mmu_linear_psize;
		ssize = mmu_kernel_ssize;
		vsid = get_kernel_vsid(ea, mmu_kernel_ssize);
		vsidkey = SLB_VSID_KERNEL;
		break;
	default:
		pr_debug("%s: invalid region access at %016llx\n", __func__, ea);
		return 1;
	}

	vsid = (vsid << slb_vsid_shift(ssize)) | vsidkey;

	vsid |= mmu_psize_defs[psize].sllp |
		((ssize == MMU_SEGSIZE_1T) ? SLB_VSID_B_1T : 0);

	slb->esid = (ea & (ssize == MMU_SEGSIZE_1T ? ESID_MASK_1T : ESID_MASK)) | SLB_ESID_V;
	slb->vsid = vsid;

	return 0;
}
EXPORT_SYMBOL_GPL(copro_calculate_slb);

void copro_flush_all_slbs(struct mm_struct *mm)
{
#ifdef CONFIG_SPU_BASE
	spu_flush_all_slbs(mm);
#endif
	cxl_slbia(mm);
}
EXPORT_SYMBOL_GPL(copro_flush_all_slbs);
Commit	Line	Data
7cd58e43	1	/*
e83d0169	2	* CoProcessor (SPU/AFU) mm fault handler
7cd58e43 JK	3	*
	4	* (C) Copyright IBM Deutschland Entwicklung GmbH 2007
	5	*
	6	* Author: Arnd Bergmann <arndb@de.ibm.com>
	7	* Author: Jeremy Kerr <jk@ozlabs.org>
	8	*
	9	* This program is free software; you can redistribute it and/or modify
	10	* it under the terms of the GNU General Public License as published by
	11	* the Free Software Foundation; either version 2, or (at your option)
	12	* any later version.
	13	*
	14	* This program is distributed in the hope that it will be useful,
	15	* but WITHOUT ANY WARRANTY; without even the implied warranty of
	16	* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
	17	* GNU General Public License for more details.
	18	*
	19	* You should have received a copy of the GNU General Public License
	20	* along with this program; if not, write to the Free Software
	21	* Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
	22	*/
	23	#include <linux/sched.h>
	24	#include <linux/mm.h>
4b16f8e2	25	#include <linux/export.h>
e83d0169	26	#include <asm/reg.h>
73d16a6e	27	#include <asm/copro.h>
be3ebfe8	28	#include <asm/spu.h>
ec249dd8	29	#include <misc/cxl-base.h>
7cd58e43 JK	30
	31	/*
	32	* This ought to be kept in sync with the powerpc specific do_page_fault
	33	* function. Currently, there are a few corner cases that we haven't had
	34	* to handle fortunately.
	35	*/
e83d0169	36	int copro_handle_mm_fault(struct mm_struct *mm, unsigned long ea,
7cd58e43 JK	37	unsigned long dsisr, unsigned *flt)
	38	{
	39	struct vm_area_struct *vma;
	40	unsigned long is_write;
	41	int ret;
	42
60ee0319	43	if (mm == NULL)
7cd58e43	44	return -EFAULT;
60ee0319 JK	45
60ee0319 JK	46	if (mm->pgd == NULL)
7cd58e43	47	return -EFAULT;
7cd58e43 JK	48
7cd58e43 JK	49	down_read(&mm->mmap_sem);
60ee0319	50	ret = -EFAULT;
7cd58e43 JK	51	vma = find_vma(mm, ea);
7cd58e43 JK	52	if (!vma)
60ee0319 JK	53	goto out_unlock;
	54
	55	if (ea < vma->vm_start) {
	56	if (!(vma->vm_flags & VM_GROWSDOWN))
	57	goto out_unlock;
	58	if (expand_stack(vma, ea))
	59	goto out_unlock;
	60	}
	61
e83d0169	62	is_write = dsisr & DSISR_ISSTORE;
7cd58e43 JK	63	if (is_write) {
7cd58e43 JK	64	if (!(vma->vm_flags & VM_WRITE))
60ee0319	65	goto out_unlock;
7cd58e43	66	} else {
7cd58e43	67	if (!(vma->vm_flags & (VM_READ \| VM_EXEC)))
60ee0319	68	goto out_unlock;
842915f5 MG	69	/*
	70	* protfault should only happen due to us
	71	* mapping a region readonly temporarily. PROT_NONE
	72	* is also covered by the VMA check above.
	73	*/
	74	WARN_ON_ONCE(dsisr & DSISR_PROTFAULT);
7cd58e43	75	}
60ee0319	76
7cd58e43	77	ret = 0;
d06063cc	78	*flt = handle_mm_fault(mm, vma, ea, is_write ? FAULT_FLAG_WRITE : 0);
7cd58e43 JK	79	if (unlikely(*flt & VM_FAULT_ERROR)) {
	80	if (*flt & VM_FAULT_OOM) {
	81	ret = -ENOMEM;
60ee0319	82	goto out_unlock;
33692f27	83	} else if (*flt & (VM_FAULT_SIGBUS \| VM_FAULT_SIGSEGV)) {
7cd58e43	84	ret = -EFAULT;
60ee0319	85	goto out_unlock;
7cd58e43 JK	86	}
	87	BUG();
	88	}
60ee0319	89
7cd58e43 JK	90	if (*flt & VM_FAULT_MAJOR)
	91	current->maj_flt++;
	92	else
	93	current->min_flt++;
7cd58e43	94
60ee0319	95	out_unlock:
7cd58e43	96	up_read(&mm->mmap_sem);
60ee0319	97	return ret;
7cd58e43	98	}
e83d0169	99	EXPORT_SYMBOL_GPL(copro_handle_mm_fault);
73d16a6e IM	100
	101	int copro_calculate_slb(struct mm_struct mm, u64 ea, struct copro_slb slb)
	102	{
85a97da9	103	u64 vsid, vsidkey;
73d16a6e IM	104	int psize, ssize;
73d16a6e IM	105
73d16a6e IM	106	switch (REGION_ID(ea)) {
	107	case USER_REGION_ID:
	108	pr_devel("%s: 0x%llx -- USER_REGION_ID\n", __func__, ea);
	109	psize = get_slice_psize(mm, ea);
	110	ssize = user_segment_size(ea);
	111	vsid = get_vsid(mm->context.id, ea, ssize);
85a97da9	112	vsidkey = SLB_VSID_USER;
73d16a6e IM	113	break;
	114	case VMALLOC_REGION_ID:
	115	pr_devel("%s: 0x%llx -- VMALLOC_REGION_ID\n", __func__, ea);
	116	if (ea < VMALLOC_END)
	117	psize = mmu_vmalloc_psize;
	118	else
	119	psize = mmu_io_psize;
	120	ssize = mmu_kernel_ssize;
	121	vsid = get_kernel_vsid(ea, mmu_kernel_ssize);
85a97da9	122	vsidkey = SLB_VSID_KERNEL;
73d16a6e IM	123	break;
	124	case KERNEL_REGION_ID:
	125	pr_devel("%s: 0x%llx -- KERNEL_REGION_ID\n", __func__, ea);
	126	psize = mmu_linear_psize;
	127	ssize = mmu_kernel_ssize;
	128	vsid = get_kernel_vsid(ea, mmu_kernel_ssize);
85a97da9	129	vsidkey = SLB_VSID_KERNEL;
73d16a6e IM	130	break;
	131	default:
	132	pr_debug("%s: invalid region access at %016llx\n", __func__, ea);
	133	return 1;
	134	}
	135
85a97da9	136	vsid = (vsid << slb_vsid_shift(ssize)) \| vsidkey;
73d16a6e IM	137
	138	vsid \|= mmu_psize_defs[psize].sllp \|
	139	((ssize == MMU_SEGSIZE_1T) ? SLB_VSID_B_1T : 0);
	140
03f54397	141	slb->esid = (ea & (ssize == MMU_SEGSIZE_1T ? ESID_MASK_1T : ESID_MASK)) \| SLB_ESID_V;
73d16a6e IM	142	slb->vsid = vsid;
	143
	144	return 0;
	145	}
	146	EXPORT_SYMBOL_GPL(copro_calculate_slb);
be3ebfe8 IM	147
	148	void copro_flush_all_slbs(struct mm_struct *mm)
	149	{
	150	#ifdef CONFIG_SPU_BASE
	151	spu_flush_all_slbs(mm);
	152	#endif
4c6d9acc	153	cxl_slbia(mm);
be3ebfe8 IM	154	}
be3ebfe8 IM	155	EXPORT_SYMBOL_GPL(copro_flush_all_slbs);