1 files changed, 257 insertions, 0 deletions

diff --git a/arch/tile/kernel/module.c b/arch/tile/kernel/module.c
new file mode 100644
index 000000000000..e2ab82b7c7e7
--- /dev/null
+++ b/arch/tile/kernel/module.c
@@ -0,0 +1,257 @@
+/*
+ * 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/opcode-tile.h>
+#include <asm/pgtable.h>
+
+#ifdef __tilegx__
+# define Elf_Rela Elf64_Rela
+# define ELF_R_SYM ELF64_R_SYM
+# define ELF_R_TYPE ELF64_R_TYPE
+#else
+# define Elf_Rela Elf32_Rela
+# define ELF_R_SYM ELF32_R_SYM
+# define ELF_R_TYPE ELF32_R_TYPE
+#endif
+
+#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;
+
+        if (size == 0)
+                return NULL;
+        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;
+
+        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_free(struct module *mod, void *module_region)
+{
+        vfree(module_region);
+        /*
+         * FIXME: If module_region == mod->init_region, trim exception
+         * table entries.
+         */
+}
+
+/* We don't need anything special. */
+int module_frob_arch_sections(Elf_Ehdr *hdr,
+                              Elf_Shdr *sechdrs,
+                              char *secstrings,
+                              struct module *mod)
+{
+        return 0;
+}
+
+int apply_relocate(Elf_Shdr *sechdrs,
+                   const char *strtab,
+                   unsigned int symindex,
+                   unsigned int relsec,
+                   struct module *me)
+{
+        pr_err("module %s: .rel relocation unsupported\n", me->name);
+        return -ENOEXEC;
+}
+
+#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_warning("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)) {
+
+#define MUNGE(func) (*location = ((*location & ~func(-1)) | func(value)))
+
+#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_warning("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;
+}
+
+int module_finalize(const Elf_Ehdr *hdr,
+                    const Elf_Shdr *sechdrs,
+                    struct module *me)
+{
+        /* FIXME: perhaps remove the "writable" bit from the TLB? */
+        return 0;
+}
+
+void module_arch_cleanup(struct module *mod)
+{
+}