Annotation of /trunk/kernel26-magellan-server/patches-2.6.27-r2/0157-2.6.27-acpi-dsdt-initrd-0.9c.patch
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Revision 728 -
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Tue Dec 23 09:41:15 2008 UTC (15 years, 9 months ago) by niro
File size: 10058 byte(s)
Tue Dec 23 09:41:15 2008 UTC (15 years, 9 months ago) by niro
File size: 10058 byte(s)
-ver bump to 2.6.27-r2: - updated to linux-2.6.27.10 - using tuxonice current-20081025 - adjusted kernel-configs to use tuxonice and enabled ufs filesystem support
1 | niro | 728 | Date: Wed, 19 Mar 2008 23:00:04 +0100 |
2 | Subject: [PATCH] ACPI: initramfs DSDT override support | ||
3 | |||
4 | Permits to load of DSDT (the main ACPI table) from initramfs. In case this | ||
5 | option is selected, the initramfs is parsed at ACPI initialization (very early | ||
6 | boot time) to look for a file called "DSDT.aml". This aims at allowing users to | ||
7 | override the DSDT without recompiling the kernel. | ||
8 | |||
9 | Version 0.9 uses a different approach for reading the initramfs which avoids | ||
10 | using the filesystem infrastructure. It leverages the initramfs unpack code to find | ||
11 | and unpack the DSDT directly into the memory. | ||
12 | |||
13 | v0.9a: Fix compilation on non-ACPI platforms by René Rebe <rene@exactcode.de> | ||
14 | v0.9b: Declare more functions __init by Jan Beulich <jbeulich@novell.com> | ||
15 | v0.9c: Allow root to be / instead of nothing, bug reported by Robert Hampovcan | ||
16 | |||
17 | Signed-off-by: Eric Piel <eric.piel@tremplin-utc.net> | ||
18 | --- | ||
19 | Documentation/acpi/dsdt-override.txt | 12 +++- | ||
20 | Documentation/acpi/initramfs-add-dsdt.sh | 43 ++++++++++++++ | ||
21 | Documentation/kernel-parameters.txt | 3 + | ||
22 | drivers/acpi/Kconfig | 11 ++++ | ||
23 | drivers/acpi/osl.c | 24 ++++++++ | ||
24 | init/initramfs.c | 89 ++++++++++++++++++++++++++++++ | ||
25 | 6 files changed, 180 insertions(+), 2 deletions(-) | ||
26 | create mode 100644 Documentation/acpi/initramfs-add-dsdt.sh | ||
27 | |||
28 | diff --git a/Documentation/acpi/dsdt-override.txt b/Documentation/acpi/dsdt-override.txt | ||
29 | index febbb1b..5008f25 100644 | ||
30 | --- a/Documentation/acpi/dsdt-override.txt | ||
31 | +++ b/Documentation/acpi/dsdt-override.txt | ||
32 | @@ -1,7 +1,15 @@ | ||
33 | -Linux supports a method of overriding the BIOS DSDT: | ||
34 | +Linux supports two methods of overriding the BIOS DSDT: | ||
35 | |||
36 | CONFIG_ACPI_CUSTOM_DSDT builds the image into the kernel. | ||
37 | |||
38 | -When to use this method is described in detail on the | ||
39 | +CONFIG_ACPI_CUSTOM_DSDT_INITRD adds the image to the initrd. | ||
40 | + | ||
41 | +When to use these methods is described in detail on the | ||
42 | Linux/ACPI home page: | ||
43 | http://www.lesswatts.org/projects/acpi/overridingDSDT.php | ||
44 | + | ||
45 | +Note that if both options are used, the DSDT supplied | ||
46 | +by the INITRD method takes precedence. | ||
47 | + | ||
48 | +Documentation/initramfs-add-dsdt.sh is provided for convenience | ||
49 | +for use with the CONFIG_ACPI_CUSTOM_DSDT_INITRD method. | ||
50 | diff --git a/Documentation/acpi/initramfs-add-dsdt.sh b/Documentation/acpi/initramfs-add-dsdt.sh | ||
51 | new file mode 100644 | ||
52 | index 0000000..17ef6e8 | ||
53 | --- /dev/null | ||
54 | +++ b/Documentation/acpi/initramfs-add-dsdt.sh | ||
55 | @@ -0,0 +1,43 @@ | ||
56 | +#!/bin/bash | ||
57 | +# Adds a DSDT file to the initrd (if it's an initramfs) | ||
58 | +# first argument is the name of archive | ||
59 | +# second argument is the name of the file to add | ||
60 | +# The file will be copied as /DSDT.aml | ||
61 | + | ||
62 | +# 20060126: fix "Premature end of file" with some old cpio (Roland Robic) | ||
63 | +# 20060205: this time it should really work | ||
64 | + | ||
65 | +# check the arguments | ||
66 | +if [ $# -ne 2 ]; then | ||
67 | + program_name=$(basename $0) | ||
68 | + echo "\ | ||
69 | +$program_name: too few arguments | ||
70 | +Usage: $program_name initrd-name.img DSDT-to-add.aml | ||
71 | +Adds a DSDT file to an initrd (in initramfs format) | ||
72 | + | ||
73 | + initrd-name.img: filename of the initrd in initramfs format | ||
74 | + DSDT-to-add.aml: filename of the DSDT file to add | ||
75 | + " 1>&2 | ||
76 | + exit 1 | ||
77 | +fi | ||
78 | + | ||
79 | +# we should check it's an initramfs | ||
80 | + | ||
81 | +tempcpio=$(mktemp -d) | ||
82 | +# cleanup on exit, hangup, interrupt, quit, termination | ||
83 | +trap 'rm -rf $tempcpio' 0 1 2 3 15 | ||
84 | + | ||
85 | +# extract the archive | ||
86 | +gunzip -c "$1" > "$tempcpio"/initramfs.cpio || exit 1 | ||
87 | + | ||
88 | +# copy the DSDT file at the root of the directory so that we can call it "/DSDT.aml" | ||
89 | +cp -f "$2" "$tempcpio"/DSDT.aml | ||
90 | + | ||
91 | +# add the file | ||
92 | +cd "$tempcpio" | ||
93 | +(echo DSDT.aml | cpio --quiet -H newc -o -A -O "$tempcpio"/initramfs.cpio) || exit 1 | ||
94 | +cd "$OLDPWD" | ||
95 | + | ||
96 | +# re-compress the archive | ||
97 | +gzip -c "$tempcpio"/initramfs.cpio > "$1" | ||
98 | + | ||
99 | diff --git a/Documentation/kernel-parameters.txt b/Documentation/kernel-parameters.txt | ||
100 | index e07c432..6849df2 100644 | ||
101 | --- a/Documentation/kernel-parameters.txt | ||
102 | +++ b/Documentation/kernel-parameters.txt | ||
103 | @@ -172,6 +172,9 @@ and is between 256 and 4096 characters. It is defined in the file | ||
104 | |||
105 | acpi_no_auto_ssdt [HW,ACPI] Disable automatic loading of SSDT | ||
106 | |||
107 | + acpi_no_initrd_override [KNL,ACPI] | ||
108 | + Disable loading custom ACPI tables from the initramfs | ||
109 | + | ||
110 | acpi_os_name= [HW,ACPI] Tell ACPI BIOS the name of the OS | ||
111 | Format: To spoof as Windows 98: ="Microsoft Windows" | ||
112 | |||
113 | diff --git a/drivers/acpi/Kconfig b/drivers/acpi/Kconfig | ||
114 | index c52fca8..8df213e 100644 | ||
115 | --- a/drivers/acpi/Kconfig | ||
116 | +++ b/drivers/acpi/Kconfig | ||
117 | @@ -303,6 +303,17 @@ config ACPI_CUSTOM_DSDT | ||
118 | bool | ||
119 | default ACPI_CUSTOM_DSDT_FILE != "" | ||
120 | |||
121 | +config ACPI_CUSTOM_DSDT_INITRD | ||
122 | + bool "Read Custom DSDT from initramfs" | ||
123 | + depends on BLK_DEV_INITRD | ||
124 | + default n | ||
125 | + help | ||
126 | + This option supports a custom DSDT by optionally loading it from initrd. | ||
127 | + See Documentation/acpi/dsdt-override.txt | ||
128 | + | ||
129 | + If you are not using this feature now, but may use it later, | ||
130 | + it is safe to say Y here. | ||
131 | + | ||
132 | config ACPI_BLACKLIST_YEAR | ||
133 | int "Disable ACPI for systems before Jan 1st this year" if X86_32 | ||
134 | default 0 | ||
135 | diff --git a/drivers/acpi/osl.c b/drivers/acpi/osl.c | ||
136 | index 235a138..c75f285 100644 | ||
137 | --- a/drivers/acpi/osl.c | ||
138 | +++ b/drivers/acpi/osl.c | ||
139 | @@ -96,6 +96,11 @@ static DEFINE_SPINLOCK(acpi_res_lock); | ||
140 | #define OSI_STRING_LENGTH_MAX 64 /* arbitrary */ | ||
141 | static char osi_additional_string[OSI_STRING_LENGTH_MAX]; | ||
142 | |||
143 | +#ifdef CONFIG_ACPI_CUSTOM_DSDT_INITRD | ||
144 | +static __initdata int acpi_no_initrd_override; | ||
145 | +extern struct acpi_table_header *acpi_find_dsdt_initrd(void); | ||
146 | +#endif | ||
147 | + | ||
148 | /* | ||
149 | * "Ode to _OSI(Linux)" | ||
150 | * | ||
151 | @@ -338,6 +343,16 @@ acpi_os_table_override(struct acpi_table_header * existing_table, | ||
152 | if (strncmp(existing_table->signature, "DSDT", 4) == 0) | ||
153 | *new_table = (struct acpi_table_header *)AmlCode; | ||
154 | #endif | ||
155 | +#ifdef CONFIG_ACPI_CUSTOM_DSDT_INITRD | ||
156 | + if ((strncmp(existing_table->signature, "DSDT", 4) == 0) && | ||
157 | + !acpi_no_initrd_override) { | ||
158 | + struct acpi_table_header *initrd_table; | ||
159 | + | ||
160 | + initrd_table = acpi_find_dsdt_initrd(); | ||
161 | + if (initrd_table) | ||
162 | + *new_table = initrd_table; | ||
163 | + } | ||
164 | +#endif | ||
165 | if (*new_table != NULL) { | ||
166 | printk(KERN_WARNING PREFIX "Override [%4.4s-%8.8s], " | ||
167 | "this is unsafe: tainting kernel\n", | ||
168 | @@ -348,6 +363,15 @@ acpi_os_table_override(struct acpi_table_header * existing_table, | ||
169 | return AE_OK; | ||
170 | } | ||
171 | |||
172 | +#ifdef CONFIG_ACPI_CUSTOM_DSDT_INITRD | ||
173 | +static int __init acpi_no_initrd_override_setup(char *s) | ||
174 | +{ | ||
175 | + acpi_no_initrd_override = 1; | ||
176 | + return 1; | ||
177 | +} | ||
178 | +__setup("acpi_no_initrd_override", acpi_no_initrd_override_setup); | ||
179 | +#endif | ||
180 | + | ||
181 | static irqreturn_t acpi_irq(int irq, void *dev_id) | ||
182 | { | ||
183 | u32 handled; | ||
184 | diff --git a/init/initramfs.c b/init/initramfs.c | ||
185 | index 8eeeccb..84f9a01 100644 | ||
186 | --- a/init/initramfs.c | ||
187 | +++ b/init/initramfs.c | ||
188 | @@ -6,6 +6,9 @@ | ||
189 | #include <linux/delay.h> | ||
190 | #include <linux/string.h> | ||
191 | #include <linux/syscalls.h> | ||
192 | +#ifdef ACPI_CONFIG | ||
193 | +#include <acpi/acpi.h> | ||
194 | +#endif | ||
195 | |||
196 | static __initdata char *message; | ||
197 | static void __init error(char *x) | ||
198 | @@ -90,6 +93,12 @@ static __initdata unsigned long body_len, name_len; | ||
199 | static __initdata uid_t uid; | ||
200 | static __initdata gid_t gid; | ||
201 | static __initdata unsigned rdev; | ||
202 | +#ifdef CONFIG_ACPI_CUSTOM_DSDT_INITRD | ||
203 | +static __initdata char *file_looked_for; | ||
204 | +static __initdata struct acpi_table_header *file_mem; | ||
205 | +#else | ||
206 | +const char *file_looked_for = NULL; | ||
207 | +#endif | ||
208 | |||
209 | static void __init parse_header(char *s) | ||
210 | { | ||
211 | @@ -123,6 +132,7 @@ static __initdata enum state { | ||
212 | SkipIt, | ||
213 | GotName, | ||
214 | CopyFile, | ||
215 | + CopyFileMem, | ||
216 | GotSymlink, | ||
217 | Reset | ||
218 | } state, next_state; | ||
219 | @@ -259,6 +269,54 @@ static void __init clean_path(char *path, mode_t mode) | ||
220 | |||
221 | static __initdata int wfd; | ||
222 | |||
223 | +#ifdef CONFIG_ACPI_CUSTOM_DSDT_INITRD | ||
224 | +static __init int is_file_looked_for(char *filename) | ||
225 | +{ | ||
226 | + char *tmp_collected = collected; | ||
227 | + if (file_looked_for == NULL) | ||
228 | + return 0; | ||
229 | + if (!S_ISREG(mode)) | ||
230 | + return 0; | ||
231 | + /* remove the leading / */ | ||
232 | + while (*tmp_collected == '/') | ||
233 | + tmp_collected++; | ||
234 | + return (strcmp(tmp_collected, file_looked_for) == 0); | ||
235 | +} | ||
236 | + | ||
237 | +static int __init do_copy_mem(void) | ||
238 | +{ | ||
239 | + static void *file_current; /* current position in the memory */ | ||
240 | + if (file_mem == NULL) { | ||
241 | + if (body_len < 4) { /* check especially against empty files */ | ||
242 | + error("file is less than 4 bytes"); | ||
243 | + return 1; | ||
244 | + } | ||
245 | + file_mem = kmalloc(body_len, GFP_ATOMIC); | ||
246 | + if (!file_mem) { | ||
247 | + error("failed to allocate enough memory"); | ||
248 | + return 1; | ||
249 | + } | ||
250 | + file_current = file_mem; | ||
251 | + } | ||
252 | + if (count >= body_len) { | ||
253 | + memcpy(file_current, victim, body_len); | ||
254 | + eat(body_len); | ||
255 | + file_looked_for = NULL; /* don't find files with same name */ | ||
256 | + state = SkipIt; | ||
257 | + return 0; | ||
258 | + } else { | ||
259 | + memcpy(file_current, victim, count); | ||
260 | + file_current += count; | ||
261 | + body_len -= count; | ||
262 | + eat(count); | ||
263 | + return 1; | ||
264 | + } | ||
265 | +} | ||
266 | +#else | ||
267 | +static inline int is_file_looked_for(char *filename) {return 0;} | ||
268 | +#define do_copy_mem NULL /* because it is used as a pointer */ | ||
269 | +#endif | ||
270 | + | ||
271 | static int __init do_name(void) | ||
272 | { | ||
273 | state = SkipIt; | ||
274 | @@ -267,6 +325,8 @@ static int __init do_name(void) | ||
275 | free_hash(); | ||
276 | return 0; | ||
277 | } | ||
278 | + if (is_file_looked_for(file_looked_for)) | ||
279 | + state = CopyFileMem; | ||
280 | if (dry_run) | ||
281 | return 0; | ||
282 | clean_path(collected, mode); | ||
283 | @@ -333,6 +393,7 @@ static __initdata int (*actions[])(void) = { | ||
284 | [SkipIt] = do_skip, | ||
285 | [GotName] = do_name, | ||
286 | [CopyFile] = do_copy, | ||
287 | + [CopyFileMem] = do_copy_mem, | ||
288 | [GotSymlink] = do_symlink, | ||
289 | [Reset] = do_reset, | ||
290 | }; | ||
291 | @@ -578,3 +639,31 @@ static int __init populate_rootfs(void) | ||
292 | return 0; | ||
293 | } | ||
294 | rootfs_initcall(populate_rootfs); | ||
295 | + | ||
296 | +#ifdef CONFIG_ACPI_CUSTOM_DSDT_INITRD | ||
297 | +struct __init acpi_table_header *acpi_find_dsdt_initrd(void) | ||
298 | +{ | ||
299 | + char *err, *ramfs_dsdt_name = "DSDT.aml"; | ||
300 | + | ||
301 | + printk(KERN_INFO "ACPI: Checking initramfs for custom DSDT\n"); | ||
302 | + file_mem = NULL; | ||
303 | + file_looked_for = ramfs_dsdt_name; | ||
304 | + err = unpack_to_rootfs((char *)initrd_start, | ||
305 | + initrd_end - initrd_start, 1); | ||
306 | + file_looked_for = NULL; | ||
307 | + | ||
308 | + if (err) { | ||
309 | + /* | ||
310 | + * Even if reading the DSDT file was successful, | ||
311 | + * we give up if the initramfs cannot be entirely read. | ||
312 | + */ | ||
313 | + kfree(file_mem); | ||
314 | + printk(KERN_ERR "ACPI: Aborded because %s.\n", err); | ||
315 | + return NULL; | ||
316 | + } | ||
317 | + if (file_mem) | ||
318 | + printk(KERN_INFO "ACPI: Found DSDT in %s.\n", ramfs_dsdt_name); | ||
319 | + | ||
320 | + return file_mem; | ||
321 | +} | ||
322 | +#endif | ||
323 | -- | ||
324 | 1.5.6.4 | ||
325 |