staging: erofs: fix warning Comparison to bool
[linux/fpc-iii.git] / arch / arm64 / kernel / machine_kexec_file.c
blob58871333737a4e5458d723dcb0fd6e5e609548da
1 // SPDX-License-Identifier: GPL-2.0
2 /*
3 * kexec_file for arm64
5 * Copyright (C) 2018 Linaro Limited
6 * Author: AKASHI Takahiro <takahiro.akashi@linaro.org>
8 * Most code is derived from arm64 port of kexec-tools
9 */
11 #define pr_fmt(fmt) "kexec_file: " fmt
13 #include <linux/ioport.h>
14 #include <linux/kernel.h>
15 #include <linux/kexec.h>
16 #include <linux/libfdt.h>
17 #include <linux/memblock.h>
18 #include <linux/of_fdt.h>
19 #include <linux/random.h>
20 #include <linux/string.h>
21 #include <linux/types.h>
22 #include <linux/vmalloc.h>
23 #include <asm/byteorder.h>
25 /* relevant device tree properties */
26 #define FDT_PROP_INITRD_START "linux,initrd-start"
27 #define FDT_PROP_INITRD_END "linux,initrd-end"
28 #define FDT_PROP_BOOTARGS "bootargs"
29 #define FDT_PROP_KASLR_SEED "kaslr-seed"
31 const struct kexec_file_ops * const kexec_file_loaders[] = {
32 &kexec_image_ops,
33 NULL
36 int arch_kimage_file_post_load_cleanup(struct kimage *image)
38 vfree(image->arch.dtb);
39 image->arch.dtb = NULL;
41 return kexec_image_post_load_cleanup_default(image);
44 static int setup_dtb(struct kimage *image,
45 unsigned long initrd_load_addr, unsigned long initrd_len,
46 char *cmdline, void *dtb)
48 int off, ret;
50 ret = fdt_path_offset(dtb, "/chosen");
51 if (ret < 0)
52 goto out;
54 off = ret;
56 /* add bootargs */
57 if (cmdline) {
58 ret = fdt_setprop_string(dtb, off, FDT_PROP_BOOTARGS, cmdline);
59 if (ret)
60 goto out;
61 } else {
62 ret = fdt_delprop(dtb, off, FDT_PROP_BOOTARGS);
63 if (ret && (ret != -FDT_ERR_NOTFOUND))
64 goto out;
67 /* add initrd-* */
68 if (initrd_load_addr) {
69 ret = fdt_setprop_u64(dtb, off, FDT_PROP_INITRD_START,
70 initrd_load_addr);
71 if (ret)
72 goto out;
74 ret = fdt_setprop_u64(dtb, off, FDT_PROP_INITRD_END,
75 initrd_load_addr + initrd_len);
76 if (ret)
77 goto out;
78 } else {
79 ret = fdt_delprop(dtb, off, FDT_PROP_INITRD_START);
80 if (ret && (ret != -FDT_ERR_NOTFOUND))
81 goto out;
83 ret = fdt_delprop(dtb, off, FDT_PROP_INITRD_END);
84 if (ret && (ret != -FDT_ERR_NOTFOUND))
85 goto out;
88 /* add kaslr-seed */
89 ret = fdt_delprop(dtb, off, FDT_PROP_KASLR_SEED);
90 if (ret == -FDT_ERR_NOTFOUND)
91 ret = 0;
92 else if (ret)
93 goto out;
95 if (rng_is_initialized()) {
96 u64 seed = get_random_u64();
97 ret = fdt_setprop_u64(dtb, off, FDT_PROP_KASLR_SEED, seed);
98 if (ret)
99 goto out;
100 } else {
101 pr_notice("RNG is not initialised: omitting \"%s\" property\n",
102 FDT_PROP_KASLR_SEED);
105 out:
106 if (ret)
107 return (ret == -FDT_ERR_NOSPACE) ? -ENOMEM : -EINVAL;
109 return 0;
113 * More space needed so that we can add initrd, bootargs and kaslr-seed.
115 #define DTB_EXTRA_SPACE 0x1000
117 static int create_dtb(struct kimage *image,
118 unsigned long initrd_load_addr, unsigned long initrd_len,
119 char *cmdline, void **dtb)
121 void *buf;
122 size_t buf_size;
123 size_t cmdline_len;
124 int ret;
126 cmdline_len = cmdline ? strlen(cmdline) : 0;
127 buf_size = fdt_totalsize(initial_boot_params)
128 + cmdline_len + DTB_EXTRA_SPACE;
130 for (;;) {
131 buf = vmalloc(buf_size);
132 if (!buf)
133 return -ENOMEM;
135 /* duplicate a device tree blob */
136 ret = fdt_open_into(initial_boot_params, buf, buf_size);
137 if (ret)
138 return -EINVAL;
140 ret = setup_dtb(image, initrd_load_addr, initrd_len,
141 cmdline, buf);
142 if (ret) {
143 vfree(buf);
144 if (ret == -ENOMEM) {
145 /* unlikely, but just in case */
146 buf_size += DTB_EXTRA_SPACE;
147 continue;
148 } else {
149 return ret;
153 /* trim it */
154 fdt_pack(buf);
155 *dtb = buf;
157 return 0;
161 int load_other_segments(struct kimage *image,
162 unsigned long kernel_load_addr,
163 unsigned long kernel_size,
164 char *initrd, unsigned long initrd_len,
165 char *cmdline)
167 struct kexec_buf kbuf;
168 void *dtb = NULL;
169 unsigned long initrd_load_addr = 0, dtb_len;
170 int ret = 0;
172 kbuf.image = image;
173 /* not allocate anything below the kernel */
174 kbuf.buf_min = kernel_load_addr + kernel_size;
176 /* load initrd */
177 if (initrd) {
178 kbuf.buffer = initrd;
179 kbuf.bufsz = initrd_len;
180 kbuf.mem = 0;
181 kbuf.memsz = initrd_len;
182 kbuf.buf_align = 0;
183 /* within 1GB-aligned window of up to 32GB in size */
184 kbuf.buf_max = round_down(kernel_load_addr, SZ_1G)
185 + (unsigned long)SZ_1G * 32;
186 kbuf.top_down = false;
188 ret = kexec_add_buffer(&kbuf);
189 if (ret)
190 goto out_err;
191 initrd_load_addr = kbuf.mem;
193 pr_debug("Loaded initrd at 0x%lx bufsz=0x%lx memsz=0x%lx\n",
194 initrd_load_addr, initrd_len, initrd_len);
197 /* load dtb */
198 ret = create_dtb(image, initrd_load_addr, initrd_len, cmdline, &dtb);
199 if (ret) {
200 pr_err("Preparing for new dtb failed\n");
201 goto out_err;
204 dtb_len = fdt_totalsize(dtb);
205 kbuf.buffer = dtb;
206 kbuf.bufsz = dtb_len;
207 kbuf.mem = 0;
208 kbuf.memsz = dtb_len;
209 /* not across 2MB boundary */
210 kbuf.buf_align = SZ_2M;
211 kbuf.buf_max = ULONG_MAX;
212 kbuf.top_down = true;
214 ret = kexec_add_buffer(&kbuf);
215 if (ret)
216 goto out_err;
217 image->arch.dtb = dtb;
218 image->arch.dtb_mem = kbuf.mem;
220 pr_debug("Loaded dtb at 0x%lx bufsz=0x%lx memsz=0x%lx\n",
221 kbuf.mem, dtb_len, dtb_len);
223 return 0;
225 out_err:
226 vfree(dtb);
227 return ret;