Initial import

1 files changed, 232 insertions, 0 deletions

diff --git a/arch/tile/kernel/module.c b/arch/tile/kernel/module.c
new file mode 100644
index 000000000..2305084c9
--- /dev/null
+++ b/arch/tile/kernel/module.c
@@ -0,0 +1,232 @@
+/*
+ * 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(npages * sizeof(struct page *), GFP_KERNEL);
+	if (pages == NULL)
+		return NULL;
+	for (; i < npages; ++i) {
+		pages[i] = alloc_page(GFP_KERNEL | __GFP_HIGHMEM);
+		if (!pages[i])
+			goto error;
+	}
+
+	area = __get_vm_area(size, VM_ALLOC, MEM_MODULE_START, MEM_MODULE_END);
+	if (!area)
+		goto error;
+	area->nr_pages = npages;
+	area->pages = pages;
+
+	if (map_vm_area(area, prot_rwx, pages)) {
+		vunmap(area->addr);
+		goto error;
+	}
+
+	return area->addr;
+
+error:
+	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;
+}