Annotation of /trunk/kernel26-xen/patches-2.6.25-r1/0157-2.6.25-acpi-dsdt-initrd-0.9a.patch
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Thu May 22 23:13:13 2008 UTC (16 years, 4 months ago) by niro
File size: 9961 byte(s)
Thu May 22 23:13:13 2008 UTC (16 years, 4 months ago) by niro
File size: 9961 byte(s)
-ver bump to 2.6.25-magellan-r1: - linux-2.6.25.4 - fbcondecor-0.9.4 - squashfs-3.3 - unionfs-2.3.3 - tuxonice-3.0-rc7 - linux-phc-0.3.0 - acpi-dstd-0.9a - reiser4 - xen-3.2.0 . ipw3945-1.2.2
1 | niro | 606 | From de31945e20bc0bd255d0264c5d97a6b24906b30a Mon Sep 17 00:00:00 2001 |
2 | From: Eric Piel <piel@localhost.(none)> | ||
3 | Date: Wed, 19 Mar 2008 23:00:04 +0100 | ||
4 | Subject: [PATCH 1/1] ACPI: initramfs DSDT override support | ||
5 | |||
6 | Permits to load of DSDT (the main ACPI table) from initramfs. In case this | ||
7 | option is selected, the initramfs is parsed at ACPI initialization (very early | ||
8 | boot time) to look for a file DSDT.aml . This aims at allowing users to | ||
9 | override the DSDT without recompiling the kernel. This is done by adding a new | ||
10 | feature to the initramfs parser so that one specific file can be directly | ||
11 | copied into memory. | ||
12 | |||
13 | This is derived from the patch v0.8 from http://gaugusch.at/kernel.shtml but | ||
14 | with kernel inclusion in mind: some clean-up's in the documentation, default | ||
15 | set to No, a kernel parameter to disable it at runtime, and most important, a | ||
16 | different approach for reading the initramfs which avoids using the filesystem | ||
17 | infrastructure. | ||
18 | |||
19 | It also contains a fix for compilation on non-ACPI platforms provided by Rene Rebe. | ||
20 | |||
21 | Signed-off-by: Eric Piel <eric.piel@tremplin-utc.net> | ||
22 | Signed-off-by: Thomas Renninger <trenn@suse.de> | ||
23 | Signed-off-by: Len Brown <len.brown@intel.com> | ||
24 | --- | ||
25 | Documentation/acpi/dsdt-override.txt | 12 ++++- | ||
26 | Documentation/acpi/initramfs-add-dsdt.sh | 43 +++++++++++++++++ | ||
27 | Documentation/kernel-parameters.txt | 3 + | ||
28 | drivers/acpi/Kconfig | 11 ++++ | ||
29 | drivers/acpi/osl.c | 24 ++++++++++ | ||
30 | init/initramfs.c | 76 ++++++++++++++++++++++++++++++ | ||
31 | 6 files changed, 167 insertions(+), 2 deletions(-) | ||
32 | create mode 100644 Documentation/acpi/initramfs-add-dsdt.sh | ||
33 | |||
34 | diff --git a/Documentation/acpi/dsdt-override.txt b/Documentation/acpi/dsdt-override.txt | ||
35 | index febbb1b..5008f25 100644 | ||
36 | --- a/Documentation/acpi/dsdt-override.txt | ||
37 | +++ b/Documentation/acpi/dsdt-override.txt | ||
38 | @@ -1,7 +1,15 @@ | ||
39 | -Linux supports a method of overriding the BIOS DSDT: | ||
40 | +Linux supports two methods of overriding the BIOS DSDT: | ||
41 | |||
42 | CONFIG_ACPI_CUSTOM_DSDT builds the image into the kernel. | ||
43 | |||
44 | -When to use this method is described in detail on the | ||
45 | +CONFIG_ACPI_CUSTOM_DSDT_INITRD adds the image to the initrd. | ||
46 | + | ||
47 | +When to use these methods is described in detail on the | ||
48 | Linux/ACPI home page: | ||
49 | http://www.lesswatts.org/projects/acpi/overridingDSDT.php | ||
50 | + | ||
51 | +Note that if both options are used, the DSDT supplied | ||
52 | +by the INITRD method takes precedence. | ||
53 | + | ||
54 | +Documentation/initramfs-add-dsdt.sh is provided for convenience | ||
55 | +for use with the CONFIG_ACPI_CUSTOM_DSDT_INITRD method. | ||
56 | diff --git a/Documentation/acpi/initramfs-add-dsdt.sh b/Documentation/acpi/initramfs-add-dsdt.sh | ||
57 | new file mode 100644 | ||
58 | index 0000000..17ef6e8 | ||
59 | --- /dev/null | ||
60 | +++ b/Documentation/acpi/initramfs-add-dsdt.sh | ||
61 | @@ -0,0 +1,43 @@ | ||
62 | +#!/bin/bash | ||
63 | +# Adds a DSDT file to the initrd (if it's an initramfs) | ||
64 | +# first argument is the name of archive | ||
65 | +# second argument is the name of the file to add | ||
66 | +# The file will be copied as /DSDT.aml | ||
67 | + | ||
68 | +# 20060126: fix "Premature end of file" with some old cpio (Roland Robic) | ||
69 | +# 20060205: this time it should really work | ||
70 | + | ||
71 | +# check the arguments | ||
72 | +if [ $# -ne 2 ]; then | ||
73 | + program_name=$(basename $0) | ||
74 | + echo "\ | ||
75 | +$program_name: too few arguments | ||
76 | +Usage: $program_name initrd-name.img DSDT-to-add.aml | ||
77 | +Adds a DSDT file to an initrd (in initramfs format) | ||
78 | + | ||
79 | + initrd-name.img: filename of the initrd in initramfs format | ||
80 | + DSDT-to-add.aml: filename of the DSDT file to add | ||
81 | + " 1>&2 | ||
82 | + exit 1 | ||
83 | +fi | ||
84 | + | ||
85 | +# we should check it's an initramfs | ||
86 | + | ||
87 | +tempcpio=$(mktemp -d) | ||
88 | +# cleanup on exit, hangup, interrupt, quit, termination | ||
89 | +trap 'rm -rf $tempcpio' 0 1 2 3 15 | ||
90 | + | ||
91 | +# extract the archive | ||
92 | +gunzip -c "$1" > "$tempcpio"/initramfs.cpio || exit 1 | ||
93 | + | ||
94 | +# copy the DSDT file at the root of the directory so that we can call it "/DSDT.aml" | ||
95 | +cp -f "$2" "$tempcpio"/DSDT.aml | ||
96 | + | ||
97 | +# add the file | ||
98 | +cd "$tempcpio" | ||
99 | +(echo DSDT.aml | cpio --quiet -H newc -o -A -O "$tempcpio"/initramfs.cpio) || exit 1 | ||
100 | +cd "$OLDPWD" | ||
101 | + | ||
102 | +# re-compress the archive | ||
103 | +gzip -c "$tempcpio"/initramfs.cpio > "$1" | ||
104 | + | ||
105 | diff --git a/Documentation/kernel-parameters.txt b/Documentation/kernel-parameters.txt | ||
106 | index 622f784..49318b9 100644 | ||
107 | --- a/Documentation/kernel-parameters.txt | ||
108 | +++ b/Documentation/kernel-parameters.txt | ||
109 | @@ -177,6 +177,9 @@ and is between 256 and 4096 characters. It is defined in the file | ||
110 | |||
111 | acpi_no_auto_ssdt [HW,ACPI] Disable automatic loading of SSDT | ||
112 | |||
113 | + acpi_no_initrd_override [KNL,ACPI] | ||
114 | + Disable loading custom ACPI tables from the initramfs | ||
115 | + | ||
116 | acpi_os_name= [HW,ACPI] Tell ACPI BIOS the name of the OS | ||
117 | Format: To spoof as Windows 98: ="Microsoft Windows" | ||
118 | |||
119 | diff --git a/drivers/acpi/Kconfig b/drivers/acpi/Kconfig | ||
120 | index b4f5e85..fbcaa06 100644 | ||
121 | --- a/drivers/acpi/Kconfig | ||
122 | +++ b/drivers/acpi/Kconfig | ||
123 | @@ -300,6 +300,17 @@ config ACPI_CUSTOM_DSDT | ||
124 | bool | ||
125 | default ACPI_CUSTOM_DSDT_FILE != "" | ||
126 | |||
127 | +config ACPI_CUSTOM_DSDT_INITRD | ||
128 | + bool "Read Custom DSDT from initramfs" | ||
129 | + depends on BLK_DEV_INITRD | ||
130 | + default n | ||
131 | + help | ||
132 | + This option supports a custom DSDT by optionally loading it from initrd. | ||
133 | + See Documentation/acpi/dsdt-override.txt | ||
134 | + | ||
135 | + If you are not using this feature now, but may use it later, | ||
136 | + it is safe to say Y here. | ||
137 | + | ||
138 | config ACPI_BLACKLIST_YEAR | ||
139 | int "Disable ACPI for systems before Jan 1st this year" if X86_32 | ||
140 | default 0 | ||
141 | diff --git a/drivers/acpi/osl.c b/drivers/acpi/osl.c | ||
142 | index a697fb6..8fa630f 100644 | ||
143 | --- a/drivers/acpi/osl.c | ||
144 | +++ b/drivers/acpi/osl.c | ||
145 | @@ -91,6 +91,11 @@ static DEFINE_SPINLOCK(acpi_res_lock); | ||
146 | #define OSI_STRING_LENGTH_MAX 64 /* arbitrary */ | ||
147 | static char osi_additional_string[OSI_STRING_LENGTH_MAX]; | ||
148 | |||
149 | +#ifdef CONFIG_ACPI_CUSTOM_DSDT_INITRD | ||
150 | +static int acpi_no_initrd_override; | ||
151 | +extern struct acpi_table_header *acpi_find_dsdt_initrd(void); | ||
152 | +#endif | ||
153 | + | ||
154 | /* | ||
155 | * "Ode to _OSI(Linux)" | ||
156 | * | ||
157 | @@ -333,6 +338,16 @@ acpi_os_table_override(struct acpi_table_header * existing_table, | ||
158 | if (strncmp(existing_table->signature, "DSDT", 4) == 0) | ||
159 | *new_table = (struct acpi_table_header *)AmlCode; | ||
160 | #endif | ||
161 | +#ifdef CONFIG_ACPI_CUSTOM_DSDT_INITRD | ||
162 | + if ((strncmp(existing_table->signature, "DSDT", 4) == 0) && | ||
163 | + !acpi_no_initrd_override) { | ||
164 | + struct acpi_table_header *initrd_table; | ||
165 | + | ||
166 | + initrd_table = acpi_find_dsdt_initrd(); | ||
167 | + if (initrd_table) | ||
168 | + *new_table = initrd_table; | ||
169 | + } | ||
170 | +#endif | ||
171 | if (*new_table != NULL) { | ||
172 | printk(KERN_WARNING PREFIX "Override [%4.4s-%8.8s], " | ||
173 | "this is unsafe: tainting kernel\n", | ||
174 | @@ -343,6 +358,15 @@ acpi_os_table_override(struct acpi_table_header * existing_table, | ||
175 | return AE_OK; | ||
176 | } | ||
177 | |||
178 | +#ifdef CONFIG_ACPI_CUSTOM_DSDT_INITRD | ||
179 | +static int __init acpi_no_initrd_override_setup(char *s) | ||
180 | +{ | ||
181 | + acpi_no_initrd_override = 1; | ||
182 | + return 1; | ||
183 | +} | ||
184 | +__setup("acpi_no_initrd_override", acpi_no_initrd_override_setup); | ||
185 | +#endif | ||
186 | + | ||
187 | static irqreturn_t acpi_irq(int irq, void *dev_id) | ||
188 | { | ||
189 | u32 handled; | ||
190 | diff --git a/init/initramfs.c b/init/initramfs.c | ||
191 | index d53fee8..495380c 100644 | ||
192 | --- a/init/initramfs.c | ||
193 | +++ b/init/initramfs.c | ||
194 | @@ -6,6 +6,9 @@ | ||
195 | #include <linux/delay.h> | ||
196 | #include <linux/string.h> | ||
197 | #include <linux/syscalls.h> | ||
198 | +#ifdef CONFIG_ACPI_CUSTOM_DSDT_INITRD | ||
199 | +#include <acpi/acpi.h> | ||
200 | +#endif | ||
201 | |||
202 | static __initdata char *message; | ||
203 | static void __init error(char *x) | ||
204 | @@ -90,6 +91,12 @@ static __initdata unsigned long body_len, name_len; | ||
205 | static __initdata uid_t uid; | ||
206 | static __initdata gid_t gid; | ||
207 | static __initdata unsigned rdev; | ||
208 | +#ifdef CONFIG_ACPI_CUSTOM_DSDT_INITRD | ||
209 | +static __initdata char *file_looked_for; | ||
210 | +static __initdata struct acpi_table_header *file_mem; | ||
211 | +#else | ||
212 | +const char *file_looked_for = NULL; | ||
213 | +#endif | ||
214 | |||
215 | static void __init parse_header(char *s) | ||
216 | { | ||
217 | @@ -123,6 +130,7 @@ static __initdata enum state { | ||
218 | SkipIt, | ||
219 | GotName, | ||
220 | CopyFile, | ||
221 | + CopyFileMem, | ||
222 | GotSymlink, | ||
223 | Reset | ||
224 | } state, next_state; | ||
225 | @@ -267,6 +275,9 @@ static int __init do_name(void) | ||
226 | free_hash(); | ||
227 | return 0; | ||
228 | } | ||
229 | + if (file_looked_for && S_ISREG(mode) && | ||
230 | + (strcmp(collected, file_looked_for) == 0)) | ||
231 | + state = CopyFileMem; | ||
232 | if (dry_run) | ||
233 | return 0; | ||
234 | clean_path(collected, mode); | ||
235 | @@ -299,6 +310,40 @@ static int __init do_name(void) | ||
236 | return 0; | ||
237 | } | ||
238 | |||
239 | +#ifdef CONFIG_ACPI_CUSTOM_DSDT_INITRD | ||
240 | +static int __init do_copy_mem(void) | ||
241 | +{ | ||
242 | + static void *file_current; /* current position in the memory */ | ||
243 | + if (file_mem == NULL) { | ||
244 | + if (body_len < 4) { /* check especially against empty files */ | ||
245 | + error("file is less than 4 bytes"); | ||
246 | + return 1; | ||
247 | + } | ||
248 | + file_mem = kmalloc(body_len, GFP_ATOMIC); | ||
249 | + if (!file_mem) { | ||
250 | + error("failed to allocate enough memory"); | ||
251 | + return 1; | ||
252 | + } | ||
253 | + file_current = file_mem; | ||
254 | + } | ||
255 | + if (count >= body_len) { | ||
256 | + memcpy(file_current, victim, body_len); | ||
257 | + eat(body_len); | ||
258 | + file_looked_for = NULL; /* don't find files with same name */ | ||
259 | + state = SkipIt; | ||
260 | + return 0; | ||
261 | + } else { | ||
262 | + memcpy(file_current, victim, count); | ||
263 | + file_current += count; | ||
264 | + body_len -= count; | ||
265 | + eat(count); | ||
266 | + return 1; | ||
267 | + } | ||
268 | +} | ||
269 | +#else | ||
270 | +#define do_copy_mem NULL | ||
271 | +#endif | ||
272 | + | ||
273 | static int __init do_copy(void) | ||
274 | { | ||
275 | if (count >= body_len) { | ||
276 | @@ -333,6 +378,7 @@ static __initdata int (*actions[])(void) = { | ||
277 | [SkipIt] = do_skip, | ||
278 | [GotName] = do_name, | ||
279 | [CopyFile] = do_copy, | ||
280 | + [CopyFileMem] = do_copy_mem, | ||
281 | [GotSymlink] = do_symlink, | ||
282 | [Reset] = do_reset, | ||
283 | }; | ||
284 | @@ -578,3 +624,31 @@ static int __init populate_rootfs(void) | ||
285 | return 0; | ||
286 | } | ||
287 | rootfs_initcall(populate_rootfs); | ||
288 | + | ||
289 | +#ifdef CONFIG_ACPI_CUSTOM_DSDT_INITRD | ||
290 | +struct acpi_table_header *acpi_find_dsdt_initrd(void) | ||
291 | +{ | ||
292 | + char *err, *ramfs_dsdt_name = "DSDT.aml"; | ||
293 | + | ||
294 | + printk(KERN_INFO "ACPI: Checking initramfs for custom DSDT\n"); | ||
295 | + file_mem = NULL; | ||
296 | + file_looked_for = ramfs_dsdt_name; | ||
297 | + err = unpack_to_rootfs((char *)initrd_start, | ||
298 | + initrd_end - initrd_start, 1); | ||
299 | + file_looked_for = NULL; | ||
300 | + | ||
301 | + if (err) { | ||
302 | + /* | ||
303 | + * Even if reading the DSDT file was successful, | ||
304 | + * we give up if the initramfs cannot be entirely read. | ||
305 | + */ | ||
306 | + kfree(file_mem); | ||
307 | + printk(KERN_ERR "ACPI: Aborded because %s.\n", err); | ||
308 | + return NULL; | ||
309 | + } | ||
310 | + if (file_mem) | ||
311 | + printk(KERN_INFO "ACPI: Found DSDT in %s.\n", ramfs_dsdt_name); | ||
312 | + | ||
313 | + return file_mem; | ||
314 | +} | ||
315 | +#endif | ||
316 | -- | ||
317 | 1.5.4.3 | ||
318 |