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authorAndré Fabian Silva Delgado <emulatorman@parabola.nu>2015-08-05 17:04:01 -0300
committerAndré Fabian Silva Delgado <emulatorman@parabola.nu>2015-08-05 17:04:01 -0300
commit57f0f512b273f60d52568b8c6b77e17f5636edc0 (patch)
tree5e910f0e82173f4ef4f51111366a3f1299037a7b /arch/tile/kernel/module.c
Initial import
Diffstat (limited to 'arch/tile/kernel/module.c')
-rw-r--r--arch/tile/kernel/module.c232
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;
+}