Orange Pi5 kernel

^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300   1) // SPDX-License-Identifier: GPL-2.0-or-later
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300   2) /*
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300   3)  * Copyright (C) 2015 Imagination Technologies
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300   4)  * Author: Alex Smith <alex.smith@imgtec.com>
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300   5)  */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300   6) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300   7) #include <linux/binfmts.h>
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300   8) #include <linux/elf.h>
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300   9) #include <linux/err.h>
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  10) #include <linux/init.h>
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  11) #include <linux/ioport.h>
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  12) #include <linux/kernel.h>
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  13) #include <linux/mm.h>
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  14) #include <linux/random.h>
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  15) #include <linux/sched.h>
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  16) #include <linux/slab.h>
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  17) #include <linux/timekeeper_internal.h>
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  18) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  19) #include <asm/abi.h>
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  20) #include <asm/mips-cps.h>
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  21) #include <asm/page.h>
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  22) #include <asm/vdso.h>
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  23) #include <vdso/helpers.h>
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  24) #include <vdso/vsyscall.h>
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  25) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  26) /* Kernel-provided data used by the VDSO. */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  27) static union mips_vdso_data mips_vdso_data __page_aligned_data;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  28) struct vdso_data *vdso_data = mips_vdso_data.data;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  29) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  30) /*
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  31)  * Mapping for the VDSO data/GIC pages. The real pages are mapped manually, as
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  32)  * what we map and where within the area they are mapped is determined at
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  33)  * runtime.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  34)  */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  35) static struct page *no_pages[] = { NULL };
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  36) static struct vm_special_mapping vdso_vvar_mapping = {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  37) 	.name = "[vvar]",
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  38) 	.pages = no_pages,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  39) };
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  40) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  41) static void __init init_vdso_image(struct mips_vdso_image *image)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  42) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  43) 	unsigned long num_pages, i;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  44) 	unsigned long data_pfn;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  45) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  46) 	BUG_ON(!PAGE_ALIGNED(image->data));
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  47) 	BUG_ON(!PAGE_ALIGNED(image->size));
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  48) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  49) 	num_pages = image->size / PAGE_SIZE;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  50) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  51) 	data_pfn = __phys_to_pfn(__pa_symbol(image->data));
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  52) 	for (i = 0; i < num_pages; i++)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  53) 		image->mapping.pages[i] = pfn_to_page(data_pfn + i);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  54) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  55) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  56) static int __init init_vdso(void)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  57) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  58) 	init_vdso_image(&vdso_image);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  59) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  60) #ifdef CONFIG_MIPS32_O32
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  61) 	init_vdso_image(&vdso_image_o32);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  62) #endif
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  63) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  64) #ifdef CONFIG_MIPS32_N32
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  65) 	init_vdso_image(&vdso_image_n32);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  66) #endif
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  67) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  68) 	return 0;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  69) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  70) subsys_initcall(init_vdso);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  71) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  72) static unsigned long vdso_base(void)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  73) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  74) 	unsigned long base = STACK_TOP;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  75) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  76) 	if (IS_ENABLED(CONFIG_MIPS_FP_SUPPORT)) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  77) 		/* Skip the delay slot emulation page */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  78) 		base += PAGE_SIZE;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  79) 	}
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  80) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  81) 	if (current->flags & PF_RANDOMIZE) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  82) 		base += get_random_int() & (VDSO_RANDOMIZE_SIZE - 1);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  83) 		base = PAGE_ALIGN(base);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  84) 	}
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  85) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  86) 	return base;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  87) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  88) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  89) int arch_setup_additional_pages(struct linux_binprm *bprm, int uses_interp)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  90) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  91) 	struct mips_vdso_image *image = current->thread.abi->vdso;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  92) 	struct mm_struct *mm = current->mm;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  93) 	unsigned long gic_size, vvar_size, size, base, data_addr, vdso_addr, gic_pfn;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  94) 	struct vm_area_struct *vma;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  95) 	int ret;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  96) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  97) 	if (mmap_write_lock_killable(mm))
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  98) 		return -EINTR;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  99) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 100) 	if (IS_ENABLED(CONFIG_MIPS_FP_SUPPORT)) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 101) 		/* Map delay slot emulation page */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 102) 		base = mmap_region(NULL, STACK_TOP, PAGE_SIZE,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 103) 				VM_READ | VM_EXEC |
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 104) 				VM_MAYREAD | VM_MAYWRITE | VM_MAYEXEC,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 105) 				0, NULL);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 106) 		if (IS_ERR_VALUE(base)) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 107) 			ret = base;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 108) 			goto out;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 109) 		}
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 110) 	}
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 111) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 112) 	/*
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 113) 	 * Determine total area size. This includes the VDSO data itself, the
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 114) 	 * data page, and the GIC user page if present. Always create a mapping
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 115) 	 * for the GIC user area if the GIC is present regardless of whether it
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 116) 	 * is the current clocksource, in case it comes into use later on. We
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 117) 	 * only map a page even though the total area is 64K, as we only need
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 118) 	 * the counter registers at the start.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 119) 	 */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 120) 	gic_size = mips_gic_present() ? PAGE_SIZE : 0;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 121) 	vvar_size = gic_size + PAGE_SIZE;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 122) 	size = vvar_size + image->size;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 123) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 124) 	/*
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 125) 	 * Find a region that's large enough for us to perform the
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 126) 	 * colour-matching alignment below.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 127) 	 */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 128) 	if (cpu_has_dc_aliases)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 129) 		size += shm_align_mask + 1;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 130) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 131) 	base = get_unmapped_area(NULL, vdso_base(), size, 0, 0);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 132) 	if (IS_ERR_VALUE(base)) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 133) 		ret = base;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 134) 		goto out;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 135) 	}
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 136) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 137) 	/*
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 138) 	 * If we suffer from dcache aliasing, ensure that the VDSO data page
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 139) 	 * mapping is coloured the same as the kernel's mapping of that memory.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 140) 	 * This ensures that when the kernel updates the VDSO data userland
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 141) 	 * will observe it without requiring cache invalidations.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 142) 	 */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 143) 	if (cpu_has_dc_aliases) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 144) 		base = __ALIGN_MASK(base, shm_align_mask);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 145) 		base += ((unsigned long)vdso_data - gic_size) & shm_align_mask;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 146) 	}
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 147) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 148) 	data_addr = base + gic_size;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 149) 	vdso_addr = data_addr + PAGE_SIZE;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 150) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 151) 	vma = _install_special_mapping(mm, base, vvar_size,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 152) 				       VM_READ | VM_MAYREAD,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 153) 				       &vdso_vvar_mapping);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 154) 	if (IS_ERR(vma)) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 155) 		ret = PTR_ERR(vma);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 156) 		goto out;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 157) 	}
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 158) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 159) 	/* Map GIC user page. */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 160) 	if (gic_size) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 161) 		gic_pfn = virt_to_phys(mips_gic_base + MIPS_GIC_USER_OFS) >> PAGE_SHIFT;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 162) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 163) 		ret = io_remap_pfn_range(vma, base, gic_pfn, gic_size,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 164) 					 pgprot_noncached(PAGE_READONLY));
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 165) 		if (ret)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 166) 			goto out;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 167) 	}
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 168) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 169) 	/* Map data page. */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 170) 	ret = remap_pfn_range(vma, data_addr,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 171) 			      virt_to_phys(vdso_data) >> PAGE_SHIFT,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 172) 			      PAGE_SIZE, PAGE_READONLY);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 173) 	if (ret)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 174) 		goto out;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 175) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 176) 	/* Map VDSO image. */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 177) 	vma = _install_special_mapping(mm, vdso_addr, image->size,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 178) 				       VM_READ | VM_EXEC |
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 179) 				       VM_MAYREAD | VM_MAYWRITE | VM_MAYEXEC,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 180) 				       &image->mapping);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 181) 	if (IS_ERR(vma)) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 182) 		ret = PTR_ERR(vma);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 183) 		goto out;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 184) 	}
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 185) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 186) 	mm->context.vdso = (void *)vdso_addr;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 187) 	ret = 0;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 188) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 189) out:
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 190) 	mmap_write_unlock(mm);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 191) 	return ret;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 192) }