Linux-2.6.12-rc2

Initial git repository build. I'm not bothering with the full history,
even though we have it. We can create a separate "historical" git
archive of that later if we want to, and in the meantime it's about
3.2GB when imported into git - space that would just make the early
git days unnecessarily complicated, when we don't have a lot of good
infrastructure for it.

Let it rip!

1 files changed, 614 insertions, 0 deletions

diff --git a/arch/ppc64/kernel/vdso.c b/arch/ppc64/kernel/vdso.c
new file mode 100644
index 00000000000..8c4597224b7
--- /dev/null
+++ b/arch/ppc64/kernel/vdso.c
@@ -0,0 +1,614 @@
+/*
+ *  linux/arch/ppc64/kernel/vdso.c
+ *
+ *    Copyright (C) 2004 Benjamin Herrenschmidt, IBM Corp.
+ *			 <benh@kernel.crashing.org>
+ *
+ *  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; either version
+ *  2 of the License, or (at your option) any later version.
+ */
+
+#include <linux/config.h>
+#include <linux/module.h>
+#include <linux/errno.h>
+#include <linux/sched.h>
+#include <linux/kernel.h>
+#include <linux/mm.h>
+#include <linux/smp.h>
+#include <linux/smp_lock.h>
+#include <linux/stddef.h>
+#include <linux/unistd.h>
+#include <linux/slab.h>
+#include <linux/user.h>
+#include <linux/elf.h>
+#include <linux/security.h>
+#include <linux/bootmem.h>
+
+#include <asm/pgtable.h>
+#include <asm/system.h>
+#include <asm/processor.h>
+#include <asm/mmu.h>
+#include <asm/mmu_context.h>
+#include <asm/machdep.h>
+#include <asm/cputable.h>
+#include <asm/sections.h>
+#include <asm/vdso.h>
+
+#undef DEBUG
+
+#ifdef DEBUG
+#define DBG(fmt...) printk(fmt)
+#else
+#define DBG(fmt...)
+#endif
+
+
+/*
+ * The vDSOs themselves are here
+ */
+extern char vdso64_start, vdso64_end;
+extern char vdso32_start, vdso32_end;
+
+static void *vdso64_kbase = &vdso64_start;
+static void *vdso32_kbase = &vdso32_start;
+
+unsigned int vdso64_pages;
+unsigned int vdso32_pages;
+
+/* Signal trampolines user addresses */
+
+unsigned long vdso64_rt_sigtramp;
+unsigned long vdso32_sigtramp;
+unsigned long vdso32_rt_sigtramp;
+
+/* Format of the patch table */
+struct vdso_patch_def
+{
+	u32		pvr_mask, pvr_value;
+	const char	*gen_name;
+	const char	*fix_name;
+};
+
+/* Table of functions to patch based on the CPU type/revision
+ *
+ * TODO: Improve by adding whole lists for each entry
+ */
+static struct vdso_patch_def vdso_patches[] = {
+	{
+		0xffff0000, 0x003a0000,		/* POWER5 */
+		"__kernel_sync_dicache", "__kernel_sync_dicache_p5"
+	},
+	{
+		0xffff0000, 0x003b0000,		/* POWER5 */
+		"__kernel_sync_dicache", "__kernel_sync_dicache_p5"
+	},
+};
+
+/*
+ * Some infos carried around for each of them during parsing at
+ * boot time.
+ */
+struct lib32_elfinfo
+{
+	Elf32_Ehdr	*hdr;		/* ptr to ELF */
+	Elf32_Sym	*dynsym;	/* ptr to .dynsym section */
+	unsigned long	dynsymsize;	/* size of .dynsym section */
+	char		*dynstr;	/* ptr to .dynstr section */
+	unsigned long	text;		/* offset of .text section in .so */
+};
+
+struct lib64_elfinfo
+{
+	Elf64_Ehdr	*hdr;
+	Elf64_Sym	*dynsym;
+	unsigned long	dynsymsize;
+	char		*dynstr;
+	unsigned long	text;
+};
+
+
+#ifdef __DEBUG
+static void dump_one_vdso_page(struct page *pg, struct page *upg)
+{
+	printk("kpg: %p (c:%d,f:%08lx)", __va(page_to_pfn(pg) << PAGE_SHIFT),
+	       page_count(pg),
+	       pg->flags);
+	if (upg/* && pg != upg*/) {
+		printk(" upg: %p (c:%d,f:%08lx)", __va(page_to_pfn(upg) << PAGE_SHIFT),
+		       page_count(upg),
+		       upg->flags);
+	}
+	printk("\n");
+}
+
+static void dump_vdso_pages(struct vm_area_struct * vma)
+{
+	int i;
+
+	if (!vma || test_thread_flag(TIF_32BIT)) {
+		printk("vDSO32 @ %016lx:\n", (unsigned long)vdso32_kbase);
+		for (i=0; i<vdso32_pages; i++) {
+			struct page *pg = virt_to_page(vdso32_kbase + i*PAGE_SIZE);
+			struct page *upg = (vma && vma->vm_mm) ?
+				follow_page(vma->vm_mm, vma->vm_start + i*PAGE_SIZE, 0)
+				: NULL;
+			dump_one_vdso_page(pg, upg);
+		}
+	}
+	if (!vma || !test_thread_flag(TIF_32BIT)) {
+		printk("vDSO64 @ %016lx:\n", (unsigned long)vdso64_kbase);
+		for (i=0; i<vdso64_pages; i++) {
+			struct page *pg = virt_to_page(vdso64_kbase + i*PAGE_SIZE);
+			struct page *upg = (vma && vma->vm_mm) ?
+				follow_page(vma->vm_mm, vma->vm_start + i*PAGE_SIZE, 0)
+				: NULL;
+			dump_one_vdso_page(pg, upg);
+		}
+	}
+}
+#endif /* DEBUG */
+
+/*
+ * Keep a dummy vma_close for now, it will prevent VMA merging.
+ */
+static void vdso_vma_close(struct vm_area_struct * vma)
+{
+}
+
+/*
+ * Our nopage() function, maps in the actual vDSO kernel pages, they will
+ * be mapped read-only by do_no_page(), and eventually COW'ed, either
+ * right away for an initial write access, or by do_wp_page().
+ */
+static struct page * vdso_vma_nopage(struct vm_area_struct * vma,
+				     unsigned long address, int *type)
+{
+	unsigned long offset = address - vma->vm_start;
+	struct page *pg;
+	void *vbase = test_thread_flag(TIF_32BIT) ? vdso32_kbase : vdso64_kbase;
+
+	DBG("vdso_vma_nopage(current: %s, address: %016lx, off: %lx)\n",
+	    current->comm, address, offset);
+
+	if (address < vma->vm_start || address > vma->vm_end)
+		return NOPAGE_SIGBUS;
+
+	/*
+	 * Last page is systemcfg, special handling here, no get_page() a
+	 * this is a reserved page
+	 */
+	if ((vma->vm_end - address) <= PAGE_SIZE)
+		return virt_to_page(systemcfg);
+
+	pg = virt_to_page(vbase + offset);
+	get_page(pg);
+	DBG(" ->page count: %d\n", page_count(pg));
+
+	return pg;
+}
+
+static struct vm_operations_struct vdso_vmops = {
+	.close	= vdso_vma_close,
+	.nopage	= vdso_vma_nopage,
+};
+
+/*
+ * This is called from binfmt_elf, we create the special vma for the
+ * vDSO and insert it into the mm struct tree
+ */
+int arch_setup_additional_pages(struct linux_binprm *bprm, int executable_stack)
+{
+	struct mm_struct *mm = current->mm;
+	struct vm_area_struct *vma;
+	unsigned long vdso_pages;
+	unsigned long vdso_base;
+
+	if (test_thread_flag(TIF_32BIT)) {
+		vdso_pages = vdso32_pages;
+		vdso_base = VDSO32_MBASE;
+	} else {
+		vdso_pages = vdso64_pages;
+		vdso_base = VDSO64_MBASE;
+	}
+
+	/* vDSO has a problem and was disabled, just don't "enable" it for the
+	 * process
+	 */
+	if (vdso_pages == 0) {
+		current->thread.vdso_base = 0;
+		return 0;
+	}
+	vma = kmem_cache_alloc(vm_area_cachep, SLAB_KERNEL);
+	if (vma == NULL)
+		return -ENOMEM;
+	if (security_vm_enough_memory(vdso_pages)) {
+		kmem_cache_free(vm_area_cachep, vma);
+		return -ENOMEM;
+	}
+	memset(vma, 0, sizeof(*vma));
+
+	/*
+	 * pick a base address for the vDSO in process space. We have a default
+	 * base of 1Mb on which we had a random offset up to 1Mb.
+	 * XXX: Add possibility for a program header to specify that location
+	 */
+	current->thread.vdso_base = vdso_base;
+	/*  + ((unsigned long)vma & 0x000ff000); */
+
+	vma->vm_mm = mm;
+	vma->vm_start = current->thread.vdso_base;
+
+	/*
+	 * the VMA size is one page more than the vDSO since systemcfg
+	 * is mapped in the last one
+	 */
+	vma->vm_end = vma->vm_start + ((vdso_pages + 1) << PAGE_SHIFT);
+
+	/*
+	 * our vma flags don't have VM_WRITE so by default, the process isn't allowed
+	 * to write those pages.
+	 * gdb can break that with ptrace interface, and thus trigger COW on those
+	 * pages but it's then your responsibility to never do that on the "data" page
+	 * of the vDSO or you'll stop getting kernel updates and your nice userland
+	 * gettimeofday will be totally dead. It's fine to use that for setting
+	 * breakpoints in the vDSO code pages though
+	 */
+	vma->vm_flags = VM_READ | VM_EXEC | VM_MAYREAD | VM_MAYWRITE | VM_MAYEXEC;
+	vma->vm_flags |= mm->def_flags;
+	vma->vm_page_prot = protection_map[vma->vm_flags & 0x7];
+	vma->vm_ops = &vdso_vmops;
+
+	down_write(&mm->mmap_sem);
+	insert_vm_struct(mm, vma);
+	mm->total_vm += (vma->vm_end - vma->vm_start) >> PAGE_SHIFT;
+	up_write(&mm->mmap_sem);
+
+	return 0;
+}
+
+static void * __init find_section32(Elf32_Ehdr *ehdr, const char *secname,
+				  unsigned long *size)
+{
+	Elf32_Shdr *sechdrs;
+	unsigned int i;
+	char *secnames;
+
+	/* Grab section headers and strings so we can tell who is who */
+	sechdrs = (void *)ehdr + ehdr->e_shoff;
+	secnames = (void *)ehdr + sechdrs[ehdr->e_shstrndx].sh_offset;
+
+	/* Find the section they want */
+	for (i = 1; i < ehdr->e_shnum; i++) {
+		if (strcmp(secnames+sechdrs[i].sh_name, secname) == 0) {
+			if (size)
+				*size = sechdrs[i].sh_size;
+			return (void *)ehdr + sechdrs[i].sh_offset;
+		}
+	}
+	*size = 0;
+	return NULL;
+}
+
+static void * __init find_section64(Elf64_Ehdr *ehdr, const char *secname,
+				  unsigned long *size)
+{
+	Elf64_Shdr *sechdrs;
+	unsigned int i;
+	char *secnames;
+
+	/* Grab section headers and strings so we can tell who is who */
+	sechdrs = (void *)ehdr + ehdr->e_shoff;
+	secnames = (void *)ehdr + sechdrs[ehdr->e_shstrndx].sh_offset;
+
+	/* Find the section they want */
+	for (i = 1; i < ehdr->e_shnum; i++) {
+		if (strcmp(secnames+sechdrs[i].sh_name, secname) == 0) {
+			if (size)
+				*size = sechdrs[i].sh_size;
+			return (void *)ehdr + sechdrs[i].sh_offset;
+		}
+	}
+	if (size)
+		*size = 0;
+	return NULL;
+}
+
+static Elf32_Sym * __init find_symbol32(struct lib32_elfinfo *lib, const char *symname)
+{
+	unsigned int i;
+	char name[32], *c;
+
+	for (i = 0; i < (lib->dynsymsize / sizeof(Elf32_Sym)); i++) {
+		if (lib->dynsym[i].st_name == 0)
+			continue;
+		strlcpy(name, lib->dynstr + lib->dynsym[i].st_name, 32);
+		c = strchr(name, '@');
+		if (c)
+			*c = 0;
+		if (strcmp(symname, name) == 0)
+			return &lib->dynsym[i];
+	}
+	return NULL;
+}
+
+static Elf64_Sym * __init find_symbol64(struct lib64_elfinfo *lib, const char *symname)
+{
+	unsigned int i;
+	char name[32], *c;
+
+	for (i = 0; i < (lib->dynsymsize / sizeof(Elf64_Sym)); i++) {
+		if (lib->dynsym[i].st_name == 0)
+			continue;
+		strlcpy(name, lib->dynstr + lib->dynsym[i].st_name, 32);
+		c = strchr(name, '@');
+		if (c)
+			*c = 0;
+		if (strcmp(symname, name) == 0)
+			return &lib->dynsym[i];
+	}
+	return NULL;
+}
+
+/* Note that we assume the section is .text and the symbol is relative to
+ * the library base
+ */
+static unsigned long __init find_function32(struct lib32_elfinfo *lib, const char *symname)
+{
+	Elf32_Sym *sym = find_symbol32(lib, symname);
+
+	if (sym == NULL) {
+		printk(KERN_WARNING "vDSO32: function %s not found !\n", symname);
+		return 0;
+	}
+	return sym->st_value - VDSO32_LBASE;
+}
+
+/* Note that we assume the section is .text and the symbol is relative to
+ * the library base
+ */
+static unsigned long __init find_function64(struct lib64_elfinfo *lib, const char *symname)
+{
+	Elf64_Sym *sym = find_symbol64(lib, symname);
+
+	if (sym == NULL) {
+		printk(KERN_WARNING "vDSO64: function %s not found !\n", symname);
+		return 0;
+	}
+#ifdef VDS64_HAS_DESCRIPTORS
+	return *((u64 *)(vdso64_kbase + sym->st_value - VDSO64_LBASE)) - VDSO64_LBASE;
+#else
+	return sym->st_value - VDSO64_LBASE;
+#endif
+}
+
+
+static __init int vdso_do_find_sections(struct lib32_elfinfo *v32,
+					struct lib64_elfinfo *v64)
+{
+	void *sect;
+
+	/*
+	 * Locate symbol tables & text section
+	 */
+
+	v32->dynsym = find_section32(v32->hdr, ".dynsym", &v32->dynsymsize);
+	v32->dynstr = find_section32(v32->hdr, ".dynstr", NULL);
+	if (v32->dynsym == NULL || v32->dynstr == NULL) {
+		printk(KERN_ERR "vDSO32: a required symbol section was not found\n");
+		return -1;
+	}
+	sect = find_section32(v32->hdr, ".text", NULL);
+	if (sect == NULL) {
+		printk(KERN_ERR "vDSO32: the .text section was not found\n");
+		return -1;
+	}
+	v32->text = sect - vdso32_kbase;
+
+	v64->dynsym = find_section64(v64->hdr, ".dynsym", &v64->dynsymsize);
+	v64->dynstr = find_section64(v64->hdr, ".dynstr", NULL);
+	if (v64->dynsym == NULL || v64->dynstr == NULL) {
+		printk(KERN_ERR "vDSO64: a required symbol section was not found\n");
+		return -1;
+	}
+	sect = find_section64(v64->hdr, ".text", NULL);
+	if (sect == NULL) {
+		printk(KERN_ERR "vDSO64: the .text section was not found\n");
+		return -1;
+	}
+	v64->text = sect - vdso64_kbase;
+
+	return 0;
+}
+
+static __init void vdso_setup_trampolines(struct lib32_elfinfo *v32,
+					  struct lib64_elfinfo *v64)
+{
+	/*
+	 * Find signal trampolines
+	 */
+
+	vdso64_rt_sigtramp	= find_function64(v64, "__kernel_sigtramp_rt64");
+	vdso32_sigtramp		= find_function32(v32, "__kernel_sigtramp32");
+	vdso32_rt_sigtramp	= find_function32(v32, "__kernel_sigtramp_rt32");
+}
+
+static __init int vdso_fixup_datapage(struct lib32_elfinfo *v32,
+				       struct lib64_elfinfo *v64)
+{
+	Elf32_Sym *sym32;
+	Elf64_Sym *sym64;
+
+	sym32 = find_symbol32(v32, "__kernel_datapage_offset");
+	if (sym32 == NULL) {
+		printk(KERN_ERR "vDSO32: Can't find symbol __kernel_datapage_offset !\n");
+		return -1;
+	}
+	*((int *)(vdso32_kbase + (sym32->st_value - VDSO32_LBASE))) =
+		(vdso32_pages << PAGE_SHIFT) - (sym32->st_value - VDSO32_LBASE);
+
+       	sym64 = find_symbol64(v64, "__kernel_datapage_offset");
+	if (sym64 == NULL) {
+		printk(KERN_ERR "vDSO64: Can't find symbol __kernel_datapage_offset !\n");
+		return -1;
+	}
+	*((int *)(vdso64_kbase + sym64->st_value - VDSO64_LBASE)) =
+		(vdso64_pages << PAGE_SHIFT) - (sym64->st_value - VDSO64_LBASE);
+
+	return 0;
+}
+
+static int vdso_do_func_patch32(struct lib32_elfinfo *v32,
+				struct lib64_elfinfo *v64,
+				const char *orig, const char *fix)
+{
+	Elf32_Sym *sym32_gen, *sym32_fix;
+
+	sym32_gen = find_symbol32(v32, orig);
+	if (sym32_gen == NULL) {
+		printk(KERN_ERR "vDSO32: Can't find symbol %s !\n", orig);
+		return -1;
+	}
+	sym32_fix = find_symbol32(v32, fix);
+	if (sym32_fix == NULL) {
+		printk(KERN_ERR "vDSO32: Can't find symbol %s !\n", fix);
+		return -1;
+	}
+	sym32_gen->st_value = sym32_fix->st_value;
+	sym32_gen->st_size = sym32_fix->st_size;
+	sym32_gen->st_info = sym32_fix->st_info;
+	sym32_gen->st_other = sym32_fix->st_other;
+	sym32_gen->st_shndx = sym32_fix->st_shndx;
+
+	return 0;
+}
+
+static int vdso_do_func_patch64(struct lib32_elfinfo *v32,
+				struct lib64_elfinfo *v64,
+				const char *orig, const char *fix)
+{
+	Elf64_Sym *sym64_gen, *sym64_fix;
+
+	sym64_gen = find_symbol64(v64, orig);
+	if (sym64_gen == NULL) {
+		printk(KERN_ERR "vDSO64: Can't find symbol %s !\n", orig);
+		return -1;
+	}
+	sym64_fix = find_symbol64(v64, fix);
+	if (sym64_fix == NULL) {
+		printk(KERN_ERR "vDSO64: Can't find symbol %s !\n", fix);
+		return -1;
+	}
+	sym64_gen->st_value = sym64_fix->st_value;
+	sym64_gen->st_size = sym64_fix->st_size;
+	sym64_gen->st_info = sym64_fix->st_info;
+	sym64_gen->st_other = sym64_fix->st_other;
+	sym64_gen->st_shndx = sym64_fix->st_shndx;
+
+	return 0;
+}
+
+static __init int vdso_fixup_alt_funcs(struct lib32_elfinfo *v32,
+				       struct lib64_elfinfo *v64)
+{
+	u32 pvr;
+	int i;
+
+	pvr = mfspr(SPRN_PVR);
+	for (i = 0; i < ARRAY_SIZE(vdso_patches); i++) {
+		struct vdso_patch_def *patch = &vdso_patches[i];
+		int match = (pvr & patch->pvr_mask) == patch->pvr_value;
+
+		DBG("patch %d (mask: %x, pvr: %x) : %s\n",
+		    i, patch->pvr_mask, patch->pvr_value, match ? "match" : "skip");
+
+		if (!match)
+			continue;
+
+		DBG("replacing %s with %s...\n", patch->gen_name, patch->fix_name);
+
+		/*
+		 * Patch the 32 bits and 64 bits symbols. Note that we do not patch
+		 * the "." symbol on 64 bits. It would be easy to do, but doesn't
+		 * seem to be necessary, patching the OPD symbol is enough.
+		 */
+		vdso_do_func_patch32(v32, v64, patch->gen_name, patch->fix_name);
+		vdso_do_func_patch64(v32, v64, patch->gen_name, patch->fix_name);
+	}
+
+	return 0;
+}
+
+
+static __init int vdso_setup(void)
+{
+	struct lib32_elfinfo	v32;
+	struct lib64_elfinfo	v64;
+
+	v32.hdr = vdso32_kbase;
+	v64.hdr = vdso64_kbase;
+
+	if (vdso_do_find_sections(&v32, &v64))
+		return -1;
+
+	if (vdso_fixup_datapage(&v32, &v64))
+		return -1;
+
+	if (vdso_fixup_alt_funcs(&v32, &v64))
+		return -1;
+
+	vdso_setup_trampolines(&v32, &v64);
+
+	return 0;
+}
+
+void __init vdso_init(void)
+{
+	int i;
+
+	vdso64_pages = (&vdso64_end - &vdso64_start) >> PAGE_SHIFT;
+	vdso32_pages = (&vdso32_end - &vdso32_start) >> PAGE_SHIFT;
+
+	DBG("vdso64_kbase: %p, 0x%x pages, vdso32_kbase: %p, 0x%x pages\n",
+	       vdso64_kbase, vdso64_pages, vdso32_kbase, vdso32_pages);
+
+	/*
+	 * Initialize the vDSO images in memory, that is do necessary
+	 * fixups of vDSO symbols, locate trampolines, etc...
+	 */
+	if (vdso_setup()) {
+		printk(KERN_ERR "vDSO setup failure, not enabled !\n");
+		/* XXX should free pages here ? */
+		vdso64_pages = vdso32_pages = 0;
+		return;
+	}
+
+	/* Make sure pages are in the correct state */
+	for (i = 0; i < vdso64_pages; i++) {
+		struct page *pg = virt_to_page(vdso64_kbase + i*PAGE_SIZE);
+		ClearPageReserved(pg);
+		get_page(pg);
+	}
+	for (i = 0; i < vdso32_pages; i++) {
+		struct page *pg = virt_to_page(vdso32_kbase + i*PAGE_SIZE);
+		ClearPageReserved(pg);
+		get_page(pg);
+	}
+}
+
+int in_gate_area_no_task(unsigned long addr)
+{
+	return 0;
+}
+
+int in_gate_area(struct task_struct *task, unsigned long addr)
+{
+	return 0;
+}
+
+struct vm_area_struct *get_gate_vma(struct task_struct *tsk)
+{
+	return NULL;
+}
+