Initial commit: OpenHarmony-v4.0-ReleaseOpenHarmony-v4.0-Release

1 files changed, 457 insertions, 0 deletions

diff --git a/arch/mips/kernel/module.c b/arch/mips/kernel/module.c
new file mode 100644
index 000000000..3c0c3d126
--- /dev/null
+++ b/arch/mips/kernel/module.c
@@ -0,0 +1,457 @@
+// SPDX-License-Identifier: GPL-2.0-or-later
+/*
+ *
+ *  Copyright (C) 2001 Rusty Russell.
+ *  Copyright (C) 2003, 2004 Ralf Baechle (ralf@linux-mips.org)
+ *  Copyright (C) 2005 Thiemo Seufer
+ */
+
+#undef DEBUG
+
+#include <linux/extable.h>
+#include <linux/moduleloader.h>
+#include <linux/elf.h>
+#include <linux/mm.h>
+#include <linux/numa.h>
+#include <linux/vmalloc.h>
+#include <linux/slab.h>
+#include <linux/fs.h>
+#include <linux/string.h>
+#include <linux/kernel.h>
+#include <linux/spinlock.h>
+#include <linux/jump_label.h>
+
+
+struct mips_hi16 {
+        struct mips_hi16 *next;
+        Elf_Addr *addr;
+        Elf_Addr value;
+};
+
+static LIST_HEAD(dbe_list);
+static DEFINE_SPINLOCK(dbe_lock);
+
+#ifdef MODULE_START
+void *module_alloc(unsigned long size)
+{
+        return __vmalloc_node_range(size, 1, MODULE_START, MODULE_END,
+                                GFP_KERNEL, PAGE_KERNEL, 0, NUMA_NO_NODE,
+                                __builtin_return_address(0));
+}
+#endif
+
+static int apply_r_mips_none(struct module *me, u32 *location,
+                             u32 base, Elf_Addr v, bool rela)
+{
+        return 0;
+}
+
+static int apply_r_mips_32(struct module *me, u32 *location,
+                           u32 base, Elf_Addr v, bool rela)
+{
+        *location = base + v;
+
+        return 0;
+}
+
+static int apply_r_mips_26(struct module *me, u32 *location,
+                           u32 base, Elf_Addr v, bool rela)
+{
+        if (v % 4) {
+                pr_err("module %s: dangerous R_MIPS_26 relocation\n",
+                       me->name);
+                return -ENOEXEC;
+        }
+
+        if ((v & 0xf0000000) != (((unsigned long)location + 4) & 0xf0000000)) {
+                pr_err("module %s: relocation overflow\n",
+                       me->name);
+                return -ENOEXEC;
+        }
+
+        *location = (*location & ~0x03ffffff) |
+                    ((base + (v >> 2)) & 0x03ffffff);
+
+        return 0;
+}
+
+static int apply_r_mips_hi16(struct module *me, u32 *location,
+                             u32 base, Elf_Addr v, bool rela)
+{
+        struct mips_hi16 *n;
+
+        if (rela) {
+                *location = (*location & 0xffff0000) |
+                            ((((long long) v + 0x8000LL) >> 16) & 0xffff);
+                return 0;
+        }
+
+        /*
+         * We cannot relocate this one now because we don't know the value of
+         * the carry we need to add.  Save the information, and let LO16 do the
+         * actual relocation.
+         */
+        n = kmalloc(sizeof *n, GFP_KERNEL);
+        if (!n)
+                return -ENOMEM;
+
+        n->addr = (Elf_Addr *)location;
+        n->value = v;
+        n->next = me->arch.r_mips_hi16_list;
+        me->arch.r_mips_hi16_list = n;
+
+        return 0;
+}
+
+static void free_relocation_chain(struct mips_hi16 *l)
+{
+        struct mips_hi16 *next;
+
+        while (l) {
+                next = l->next;
+                kfree(l);
+                l = next;
+        }
+}
+
+static int apply_r_mips_lo16(struct module *me, u32 *location,
+                             u32 base, Elf_Addr v, bool rela)
+{
+        unsigned long insnlo = base;
+        struct mips_hi16 *l;
+        Elf_Addr val, vallo;
+
+        if (rela) {
+                *location = (*location & 0xffff0000) | (v & 0xffff);
+                return 0;
+        }
+
+        /* Sign extend the addend we extract from the lo insn.  */
+        vallo = ((insnlo & 0xffff) ^ 0x8000) - 0x8000;
+
+        if (me->arch.r_mips_hi16_list != NULL) {
+                l = me->arch.r_mips_hi16_list;
+                while (l != NULL) {
+                        struct mips_hi16 *next;
+                        unsigned long insn;
+
+                        /*
+                         * The value for the HI16 had best be the same.
+                         */
+                        if (v != l->value)
+                                goto out_danger;
+
+                        /*
+                         * Do the HI16 relocation.  Note that we actually don't
+                         * need to know anything about the LO16 itself, except
+                         * where to find the low 16 bits of the addend needed
+                         * by the LO16.
+                         */
+                        insn = *l->addr;
+                        val = ((insn & 0xffff) << 16) + vallo;
+                        val += v;
+
+                        /*
+                         * Account for the sign extension that will happen in
+                         * the low bits.
+                         */
+                        val = ((val >> 16) + ((val & 0x8000) != 0)) & 0xffff;
+
+                        insn = (insn & ~0xffff) | val;
+                        *l->addr = insn;
+
+                        next = l->next;
+                        kfree(l);
+                        l = next;
+                }
+
+                me->arch.r_mips_hi16_list = NULL;
+        }
+
+        /*
+         * Ok, we're done with the HI16 relocs.  Now deal with the LO16.
+         */
+        val = v + vallo;
+        insnlo = (insnlo & ~0xffff) | (val & 0xffff);
+        *location = insnlo;
+
+        return 0;
+
+out_danger:
+        free_relocation_chain(l);
+        me->arch.r_mips_hi16_list = NULL;
+
+        pr_err("module %s: dangerous R_MIPS_LO16 relocation\n", me->name);
+
+        return -ENOEXEC;
+}
+
+static int apply_r_mips_pc(struct module *me, u32 *location, u32 base,
+                           Elf_Addr v, unsigned int bits)
+{
+        unsigned long mask = GENMASK(bits - 1, 0);
+        unsigned long se_bits;
+        long offset;
+
+        if (v % 4) {
+                pr_err("module %s: dangerous R_MIPS_PC%u relocation\n",
+                       me->name, bits);
+                return -ENOEXEC;
+        }
+
+        /* retrieve & sign extend implicit addend if any */
+        offset = base & mask;
+        offset |= (offset & BIT(bits - 1)) ? ~mask : 0;
+
+        offset += ((long)v - (long)location) >> 2;
+
+        /* check the sign bit onwards are identical - ie. we didn't overflow */
+        se_bits = (offset & BIT(bits - 1)) ? ~0ul : 0;
+        if ((offset & ~mask) != (se_bits & ~mask)) {
+                pr_err("module %s: relocation overflow\n", me->name);
+                return -ENOEXEC;
+        }
+
+        *location = (*location & ~mask) | (offset & mask);
+
+        return 0;
+}
+
+static int apply_r_mips_pc16(struct module *me, u32 *location,
+                             u32 base, Elf_Addr v, bool rela)
+{
+        return apply_r_mips_pc(me, location, base, v, 16);
+}
+
+static int apply_r_mips_pc21(struct module *me, u32 *location,
+                             u32 base, Elf_Addr v, bool rela)
+{
+        return apply_r_mips_pc(me, location, base, v, 21);
+}
+
+static int apply_r_mips_pc26(struct module *me, u32 *location,
+                             u32 base, Elf_Addr v, bool rela)
+{
+        return apply_r_mips_pc(me, location, base, v, 26);
+}
+
+static int apply_r_mips_64(struct module *me, u32 *location,
+                           u32 base, Elf_Addr v, bool rela)
+{
+        if (WARN_ON(!rela))
+                return -EINVAL;
+
+        *(Elf_Addr *)location = v;
+
+        return 0;
+}
+
+static int apply_r_mips_higher(struct module *me, u32 *location,
+                               u32 base, Elf_Addr v, bool rela)
+{
+        if (WARN_ON(!rela))
+                return -EINVAL;
+
+        *location = (*location & 0xffff0000) |
+                    ((((long long)v + 0x80008000LL) >> 32) & 0xffff);
+
+        return 0;
+}
+
+static int apply_r_mips_highest(struct module *me, u32 *location,
+                                u32 base, Elf_Addr v, bool rela)
+{
+        if (WARN_ON(!rela))
+                return -EINVAL;
+
+        *location = (*location & 0xffff0000) |
+                    ((((long long)v + 0x800080008000LL) >> 48) & 0xffff);
+
+        return 0;
+}
+
+/**
+ * reloc_handler() - Apply a particular relocation to a module
+ * @me: the module to apply the reloc to
+ * @location: the address at which the reloc is to be applied
+ * @base: the existing value at location for REL-style; 0 for RELA-style
+ * @v: the value of the reloc, with addend for RELA-style
+ *
+ * Each implemented reloc_handler function applies a particular type of
+ * relocation to the module @me. Relocs that may be found in either REL or RELA
+ * variants can be handled by making use of the @base & @v parameters which are
+ * set to values which abstract the difference away from the particular reloc
+ * implementations.
+ *
+ * Return: 0 upon success, else -ERRNO
+ */
+typedef int (*reloc_handler)(struct module *me, u32 *location,
+                             u32 base, Elf_Addr v, bool rela);
+
+/* The handlers for known reloc types */
+static reloc_handler reloc_handlers[] = {
+        [R_MIPS_NONE]           = apply_r_mips_none,
+        [R_MIPS_32]             = apply_r_mips_32,
+        [R_MIPS_26]             = apply_r_mips_26,
+        [R_MIPS_HI16]           = apply_r_mips_hi16,
+        [R_MIPS_LO16]           = apply_r_mips_lo16,
+        [R_MIPS_PC16]           = apply_r_mips_pc16,
+        [R_MIPS_64]             = apply_r_mips_64,
+        [R_MIPS_HIGHER]         = apply_r_mips_higher,
+        [R_MIPS_HIGHEST]        = apply_r_mips_highest,
+        [R_MIPS_PC21_S2]        = apply_r_mips_pc21,
+        [R_MIPS_PC26_S2]        = apply_r_mips_pc26,
+};
+
+static int __apply_relocate(Elf_Shdr *sechdrs, const char *strtab,
+                            unsigned int symindex, unsigned int relsec,
+                            struct module *me, bool rela)
+{
+        union {
+                Elf_Mips_Rel *rel;
+                Elf_Mips_Rela *rela;
+        } r;
+        reloc_handler handler;
+        Elf_Sym *sym;
+        u32 *location, base;
+        unsigned int i, type;
+        Elf_Addr v;
+        int err = 0;
+        size_t reloc_sz;
+
+        pr_debug("Applying relocate section %u to %u\n", relsec,
+               sechdrs[relsec].sh_info);
+
+        r.rel = (void *)sechdrs[relsec].sh_addr;
+        reloc_sz = rela ? sizeof(*r.rela) : sizeof(*r.rel);
+        me->arch.r_mips_hi16_list = NULL;
+        for (i = 0; i < sechdrs[relsec].sh_size / reloc_sz; i++) {
+                /* This is where to make the change */
+                location = (void *)sechdrs[sechdrs[relsec].sh_info].sh_addr
+                        + r.rel->r_offset;
+                /* This is the symbol it is referring to */
+                sym = (Elf_Sym *)sechdrs[symindex].sh_addr
+                        + ELF_MIPS_R_SYM(*r.rel);
+                if (sym->st_value >= -MAX_ERRNO) {
+                        /* Ignore unresolved weak symbol */
+                        if (ELF_ST_BIND(sym->st_info) == STB_WEAK)
+                                continue;
+                        pr_warn("%s: Unknown symbol %s\n",
+                                me->name, strtab + sym->st_name);
+                        err = -ENOENT;
+                        goto out;
+                }
+
+                type = ELF_MIPS_R_TYPE(*r.rel);
+                if (type < ARRAY_SIZE(reloc_handlers))
+                        handler = reloc_handlers[type];
+                else
+                        handler = NULL;
+
+                if (!handler) {
+                        pr_err("%s: Unknown relocation type %u\n",
+                               me->name, type);
+                        err = -EINVAL;
+                        goto out;
+                }
+
+                if (rela) {
+                        v = sym->st_value + r.rela->r_addend;
+                        base = 0;
+                        r.rela = &r.rela[1];
+                } else {
+                        v = sym->st_value;
+                        base = *location;
+                        r.rel = &r.rel[1];
+                }
+
+                err = handler(me, location, base, v, rela);
+                if (err)
+                        goto out;
+        }
+
+out:
+        /*
+         * Normally the hi16 list should be deallocated at this point. A
+         * malformed binary however could contain a series of R_MIPS_HI16
+         * relocations not followed by a R_MIPS_LO16 relocation, or if we hit
+         * an error processing a reloc we might have gotten here before
+         * reaching the R_MIPS_LO16. In either case, free up the list and
+         * return an error.
+         */
+        if (me->arch.r_mips_hi16_list) {
+                free_relocation_chain(me->arch.r_mips_hi16_list);
+                me->arch.r_mips_hi16_list = NULL;
+                err = err ?: -ENOEXEC;
+        }
+
+        return err;
+}
+
+int apply_relocate(Elf_Shdr *sechdrs, const char *strtab,
+                   unsigned int symindex, unsigned int relsec,
+                   struct module *me)
+{
+        return __apply_relocate(sechdrs, strtab, symindex, relsec, me, false);
+}
+
+#ifdef CONFIG_MODULES_USE_ELF_RELA
+int apply_relocate_add(Elf_Shdr *sechdrs, const char *strtab,
+                       unsigned int symindex, unsigned int relsec,
+                       struct module *me)
+{
+        return __apply_relocate(sechdrs, strtab, symindex, relsec, me, true);
+}
+#endif /* CONFIG_MODULES_USE_ELF_RELA */
+
+/* Given an address, look for it in the module exception tables. */
+const struct exception_table_entry *search_module_dbetables(unsigned long addr)
+{
+        unsigned long flags;
+        const struct exception_table_entry *e = NULL;
+        struct mod_arch_specific *dbe;
+
+        spin_lock_irqsave(&dbe_lock, flags);
+        list_for_each_entry(dbe, &dbe_list, dbe_list) {
+                e = search_extable(dbe->dbe_start,
+                                   dbe->dbe_end - dbe->dbe_start, addr);
+                if (e)
+                        break;
+        }
+        spin_unlock_irqrestore(&dbe_lock, flags);
+
+        /* Now, if we found one, we are running inside it now, hence
+           we cannot unload the module, hence no refcnt needed. */
+        return e;
+}
+
+/* Put in dbe list if necessary. */
+int module_finalize(const Elf_Ehdr *hdr,
+                    const Elf_Shdr *sechdrs,
+                    struct module *me)
+{
+        const Elf_Shdr *s;
+        char *secstrings = (void *)hdr + sechdrs[hdr->e_shstrndx].sh_offset;
+
+        /* Make jump label nops. */
+        jump_label_apply_nops(me);
+
+        INIT_LIST_HEAD(&me->arch.dbe_list);
+        for (s = sechdrs; s < sechdrs + hdr->e_shnum; s++) {
+                if (strcmp("__dbe_table", secstrings + s->sh_name) != 0)
+                        continue;
+                me->arch.dbe_start = (void *)s->sh_addr;
+                me->arch.dbe_end = (void *)s->sh_addr + s->sh_size;
+                spin_lock_irq(&dbe_lock);
+                list_add(&me->arch.dbe_list, &dbe_list);
+                spin_unlock_irq(&dbe_lock);
+        }
+        return 0;
+}
+
+void module_arch_cleanup(struct module *mod)
+{
+        spin_lock_irq(&dbe_lock);
+        list_del(&mod->arch.dbe_list);
+        spin_unlock_irq(&dbe_lock);
+}