[deliverable/linux.git] / arch / tile / kernel / module.c

/*
 * Copyright 2010 Tilera Corporation. All Rights Reserved.
 *
 *   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, version 2.
 *
 *   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, GOOD TITLE or
 *   NON INFRINGEMENT.  See the GNU General Public License for
 *   more details.
 *
 * Based on i386 version, copyright (C) 2001 Rusty Russell.
 */

#include <linux/moduleloader.h>
#include <linux/elf.h>
#include <linux/vmalloc.h>
#include <linux/fs.h>
#include <linux/string.h>
#include <linux/kernel.h>
#include <asm/pgtable.h>
#include <asm/homecache.h>
#include <arch/opcode.h>

#ifdef MODULE_DEBUG
#define DEBUGP printk
#else
#define DEBUGP(fmt...)
#endif

/*
 * Allocate some address space in the range MEM_MODULE_START to
 * MEM_MODULE_END and populate it with memory.
 */
void *module_alloc(unsigned long size)
{
	struct page **pages;
	pgprot_t prot_rwx = __pgprot(_PAGE_KERNEL | _PAGE_KERNEL_EXEC);
	struct vm_struct *area;
	int i = 0;
	int npages;

	npages = (size + PAGE_SIZE - 1) / PAGE_SIZE;
	pages = kmalloc_array(npages, sizeof(*pages), GFP_KERNEL);
	if (pages == NULL)
		return NULL;
	for (; i < npages; ++i) {
		pages[i] = alloc_page(GFP_KERNEL | __GFP_HIGHMEM);
		if (!pages[i])
			goto free_pages;
	}

	area = __get_vm_area(size, VM_ALLOC, MEM_MODULE_START, MEM_MODULE_END);
	if (!area)
		goto free_pages;
	area->nr_pages = npages;
	area->pages = pages;

	if (map_vm_area(area, prot_rwx, pages)) {
		vunmap(area->addr);
		goto free_pages;
	}

	return area->addr;
 free_pages:
	while (--i >= 0)
		__free_page(pages[i]);
	kfree(pages);
	return NULL;
}


/* Free memory returned from module_alloc */
void module_memfree(void *module_region)
{
	vfree(module_region);

	/* Globally flush the L1 icache. */
	flush_remote(0, HV_FLUSH_EVICT_L1I, cpu_online_mask,
		     0, 0, 0, NULL, NULL, 0);

	/*
	 * FIXME: Add module_arch_freeing_init to trim exception
	 * table entries.
	 */
}

#ifdef __tilegx__
/*
 * Validate that the high 16 bits of "value" is just the sign-extension of
 * the low 48 bits.
 */
static int validate_hw2_last(long value, struct module *me)
{
	if (((value << 16) >> 16) != value) {
		pr_warn("module %s: Out of range HW2_LAST value %#lx\n",
			me->name, value);
		return 0;
	}
	return 1;
}

/*
 * Validate that "value" isn't too big to hold in a JumpOff relocation.
 */
static int validate_jumpoff(long value)
{
	/* Determine size of jump offset. */
	int shift = __builtin_clzl(get_JumpOff_X1(create_JumpOff_X1(-1)));

	/* Check to see if it fits into the relocation slot. */
	long f = get_JumpOff_X1(create_JumpOff_X1(value));
	f = (f << shift) >> shift;

	return f == value;
}
#endif

int apply_relocate_add(Elf_Shdr *sechdrs,
		       const char *strtab,
		       unsigned int symindex,
		       unsigned int relsec,
		       struct module *me)
{
	unsigned int i;
	Elf_Rela *rel = (void *)sechdrs[relsec].sh_addr;
	Elf_Sym *sym;
	u64 *location;
	unsigned long value;

	DEBUGP("Applying relocate section %u to %u\n", relsec,
	       sechdrs[relsec].sh_info);
	for (i = 0; i < sechdrs[relsec].sh_size / sizeof(*rel); i++) {
		/* This is where to make the change */
		location = (void *)sechdrs[sechdrs[relsec].sh_info].sh_addr
			+ rel[i].r_offset;
		/*
		 * This is the symbol it is referring to.
		 * Note that all undefined symbols have been resolved.
		 */
		sym = (Elf_Sym *)sechdrs[symindex].sh_addr
			+ ELF_R_SYM(rel[i].r_info);
		value = sym->st_value + rel[i].r_addend;

		switch (ELF_R_TYPE(rel[i].r_info)) {

#ifdef __LITTLE_ENDIAN
# define MUNGE(func) \
	(*location = ((*location & ~func(-1)) | func(value)))
#else
/*
 * Instructions are always little-endian, so when we read them as data,
 * we have to swap them around before and after modifying them.
 */
# define MUNGE(func) \
	(*location = swab64((swab64(*location) & ~func(-1)) | func(value)))
#endif

#ifndef __tilegx__
		case R_TILE_32:
			*(uint32_t *)location = value;
			break;
		case R_TILE_IMM16_X0_HA:
			value = (value + 0x8000) >> 16;
			/*FALLTHROUGH*/
		case R_TILE_IMM16_X0_LO:
			MUNGE(create_Imm16_X0);
			break;
		case R_TILE_IMM16_X1_HA:
			value = (value + 0x8000) >> 16;
			/*FALLTHROUGH*/
		case R_TILE_IMM16_X1_LO:
			MUNGE(create_Imm16_X1);
			break;
		case R_TILE_JOFFLONG_X1:
			value -= (unsigned long) location;  /* pc-relative */
			value = (long) value >> 3;     /* count by instrs */
			MUNGE(create_JOffLong_X1);
			break;
#else
		case R_TILEGX_64:
			*location = value;
			break;
		case R_TILEGX_IMM16_X0_HW2_LAST:
			if (!validate_hw2_last(value, me))
				return -ENOEXEC;
			value >>= 16;
			/*FALLTHROUGH*/
		case R_TILEGX_IMM16_X0_HW1:
			value >>= 16;
			/*FALLTHROUGH*/
		case R_TILEGX_IMM16_X0_HW0:
			MUNGE(create_Imm16_X0);
			break;
		case R_TILEGX_IMM16_X1_HW2_LAST:
			if (!validate_hw2_last(value, me))
				return -ENOEXEC;
			value >>= 16;
			/*FALLTHROUGH*/
		case R_TILEGX_IMM16_X1_HW1:
			value >>= 16;
			/*FALLTHROUGH*/
		case R_TILEGX_IMM16_X1_HW0:
			MUNGE(create_Imm16_X1);
			break;
		case R_TILEGX_JUMPOFF_X1:
			value -= (unsigned long) location;  /* pc-relative */
			value = (long) value >> 3;     /* count by instrs */
			if (!validate_jumpoff(value)) {
				pr_warn("module %s: Out of range jump to %#llx at %#llx (%p)\n",
					me->name,
					sym->st_value + rel[i].r_addend,
					rel[i].r_offset, location);
				return -ENOEXEC;
			}
			MUNGE(create_JumpOff_X1);
			break;
#endif

#undef MUNGE

		default:
			pr_err("module %s: Unknown relocation: %d\n",
			       me->name, (int) ELF_R_TYPE(rel[i].r_info));
			return -ENOEXEC;
		}
	}
	return 0;
}
Commit	Line	Data
867e359b CM	1	/*
	2	* Copyright 2010 Tilera Corporation. All Rights Reserved.
	3	*
	4	* This program is free software; you can redistribute it and/or
	5	* modify it under the terms of the GNU General Public License
	6	* as published by the Free Software Foundation, version 2.
	7	*
	8	* This program is distributed in the hope that it will be useful, but
	9	* WITHOUT ANY WARRANTY; without even the implied warranty of
	10	* MERCHANTABILITY OR FITNESS FOR A PARTICULAR PURPOSE, GOOD TITLE or
	11	* NON INFRINGEMENT. See the GNU General Public License for
	12	* more details.
	13	*
	14	* Based on i386 version, copyright (C) 2001 Rusty Russell.
	15	*/
	16
	17	#include <linux/moduleloader.h>
	18	#include <linux/elf.h>
	19	#include <linux/vmalloc.h>
	20	#include <linux/fs.h>
	21	#include <linux/string.h>
	22	#include <linux/kernel.h>
867e359b	23	#include <asm/pgtable.h>
229f4df1	24	#include <asm/homecache.h>
eb7c792d	25	#include <arch/opcode.h>
867e359b	26
867e359b CM	27	#ifdef MODULE_DEBUG
	28	#define DEBUGP printk
	29	#else
	30	#define DEBUGP(fmt...)
	31	#endif
	32
	33	/*
	34	* Allocate some address space in the range MEM_MODULE_START to
	35	* MEM_MODULE_END and populate it with memory.
	36	*/
	37	void *module_alloc(unsigned long size)
	38	{
	39	struct page **pages;
	40	pgprot_t prot_rwx = __pgprot(_PAGE_KERNEL \| _PAGE_KERNEL_EXEC);
	41	struct vm_struct *area;
	42	int i = 0;
	43	int npages;
	44
867e359b	45	npages = (size + PAGE_SIZE - 1) / PAGE_SIZE;
4b0d0f3f	46	pages = kmalloc_array(npages, sizeof(*pages), GFP_KERNEL);
867e359b CM	47	if (pages == NULL)
	48	return NULL;
	49	for (; i < npages; ++i) {
	50	pages[i] = alloc_page(GFP_KERNEL \| __GFP_HIGHMEM);
	51	if (!pages[i])
c11c12c6	52	goto free_pages;
867e359b CM	53	}
	54
	55	area = __get_vm_area(size, VM_ALLOC, MEM_MODULE_START, MEM_MODULE_END);
	56	if (!area)
c11c12c6	57	goto free_pages;
5f220704 CM	58	area->nr_pages = npages;
5f220704 CM	59	area->pages = pages;
867e359b	60
f6f8ed47	61	if (map_vm_area(area, prot_rwx, pages)) {
867e359b	62	vunmap(area->addr);
c11c12c6	63	goto free_pages;
867e359b CM	64	}
	65
	66	return area->addr;
c11c12c6	67	free_pages:
867e359b CM	68	while (--i >= 0)
	69	__free_page(pages[i]);
	70	kfree(pages);
	71	return NULL;
	72	}
	73
	74
	75	/* Free memory returned from module_alloc */
be1f221c	76	void module_memfree(void *module_region)
867e359b CM	77	{
867e359b CM	78	vfree(module_region);
229f4df1 CM	79
	80	/* Globally flush the L1 icache. */
	81	flush_remote(0, HV_FLUSH_EVICT_L1I, cpu_online_mask,
	82	0, 0, 0, NULL, NULL, 0);
	83
867e359b	84	/*
d453cded	85	* FIXME: Add module_arch_freeing_init to trim exception
867e359b CM	86	* table entries.
	87	*/
	88	}
	89
867e359b CM	90	#ifdef __tilegx__
	91	/*
	92	* Validate that the high 16 bits of "value" is just the sign-extension of
	93	* the low 48 bits.
	94	*/
	95	static int validate_hw2_last(long value, struct module *me)
	96	{
	97	if (((value << 16) >> 16) != value) {
f4743673 JP	98	pr_warn("module %s: Out of range HW2_LAST value %#lx\n",
f4743673 JP	99	me->name, value);
867e359b CM	100	return 0;
	101	}
	102	return 1;
	103	}
	104
	105	/*
	106	* Validate that "value" isn't too big to hold in a JumpOff relocation.
	107	*/
	108	static int validate_jumpoff(long value)
	109	{
	110	/* Determine size of jump offset. */
	111	int shift = __builtin_clzl(get_JumpOff_X1(create_JumpOff_X1(-1)));
	112
	113	/* Check to see if it fits into the relocation slot. */
	114	long f = get_JumpOff_X1(create_JumpOff_X1(value));
	115	f = (f << shift) >> shift;
	116
	117	return f == value;
	118	}
	119	#endif
	120
	121	int apply_relocate_add(Elf_Shdr *sechdrs,
	122	const char *strtab,
	123	unsigned int symindex,
	124	unsigned int relsec,
	125	struct module *me)
	126	{
	127	unsigned int i;
	128	Elf_Rela rel = (void )sechdrs[relsec].sh_addr;
	129	Elf_Sym *sym;
	130	u64 *location;
	131	unsigned long value;
	132
	133	DEBUGP("Applying relocate section %u to %u\n", relsec,
	134	sechdrs[relsec].sh_info);
	135	for (i = 0; i < sechdrs[relsec].sh_size / sizeof(*rel); i++) {
	136	/* This is where to make the change */
	137	location = (void *)sechdrs[sechdrs[relsec].sh_info].sh_addr
	138	+ rel[i].r_offset;
	139	/*
	140	* This is the symbol it is referring to.
	141	* Note that all undefined symbols have been resolved.
	142	*/
	143	sym = (Elf_Sym *)sechdrs[symindex].sh_addr
	144	+ ELF_R_SYM(rel[i].r_info);
	145	value = sym->st_value + rel[i].r_addend;
	146
	147	switch (ELF_R_TYPE(rel[i].r_info)) {
	148
1efea40d CM	149	#ifdef __LITTLE_ENDIAN
	150	# define MUNGE(func) \
	151	(location = ((location & ~func(-1)) \| func(value)))
	152	#else
	153	/*
	154	* Instructions are always little-endian, so when we read them as data,
	155	* we have to swap them around before and after modifying them.
	156	*/
	157	# define MUNGE(func) \
	158	(location = swab64((swab64(location) & ~func(-1)) \| func(value)))
	159	#endif
867e359b CM	160
	161	#ifndef __tilegx__
	162	case R_TILE_32:
	163	(uint32_t )location = value;
	164	break;
	165	case R_TILE_IMM16_X0_HA:
	166	value = (value + 0x8000) >> 16;
	167	/FALLTHROUGH/
	168	case R_TILE_IMM16_X0_LO:
	169	MUNGE(create_Imm16_X0);
	170	break;
	171	case R_TILE_IMM16_X1_HA:
	172	value = (value + 0x8000) >> 16;
	173	/FALLTHROUGH/
	174	case R_TILE_IMM16_X1_LO:
	175	MUNGE(create_Imm16_X1);
	176	break;
	177	case R_TILE_JOFFLONG_X1:
	178	value -= (unsigned long) location; /* pc-relative */
	179	value = (long) value >> 3; /* count by instrs */
	180	MUNGE(create_JOffLong_X1);
	181	break;
	182	#else
	183	case R_TILEGX_64:
	184	*location = value;
	185	break;
	186	case R_TILEGX_IMM16_X0_HW2_LAST:
	187	if (!validate_hw2_last(value, me))
	188	return -ENOEXEC;
	189	value >>= 16;
	190	/FALLTHROUGH/
	191	case R_TILEGX_IMM16_X0_HW1:
	192	value >>= 16;
	193	/FALLTHROUGH/
	194	case R_TILEGX_IMM16_X0_HW0:
	195	MUNGE(create_Imm16_X0);
	196	break;
	197	case R_TILEGX_IMM16_X1_HW2_LAST:
	198	if (!validate_hw2_last(value, me))
	199	return -ENOEXEC;
	200	value >>= 16;
	201	/FALLTHROUGH/
	202	case R_TILEGX_IMM16_X1_HW1:
	203	value >>= 16;
	204	/FALLTHROUGH/
	205	case R_TILEGX_IMM16_X1_HW0:
	206	MUNGE(create_Imm16_X1);
	207	break;
	208	case R_TILEGX_JUMPOFF_X1:
	209	value -= (unsigned long) location; /* pc-relative */
	210	value = (long) value >> 3; /* count by instrs */
	211	if (!validate_jumpoff(value)) {
f4743673 JP	212	pr_warn("module %s: Out of range jump to %#llx at %#llx (%p)\n",
	213	me->name,
	214	sym->st_value + rel[i].r_addend,
	215	rel[i].r_offset, location);
867e359b CM	216	return -ENOEXEC;
	217	}
	218	MUNGE(create_JumpOff_X1);
	219	break;
	220	#endif
	221
	222	#undef MUNGE
	223
	224	default:
0707ad30	225	pr_err("module %s: Unknown relocation: %d\n",
867e359b CM	226	me->name, (int) ELF_R_TYPE(rel[i].r_info));
	227	return -ENOEXEC;
	228	}
	229	}
	230	return 0;
	231	}