ACPI: Remove ACPI_CUSTOM_DSDT_INITRD option

This essentially reverts commit 71fc47a ("ACPI: basic initramfs DSDT override support"), because the code simply isn't ready. It did ugly things to the init sequence to populate the rootfs image early, but that just ended up showing other problems with the whole approach. The fact is, the VFS layer simply isn't initialized this early, and the relevant ACPI code should either run much later, or this shouldn't be done at all. For 2.6.25, we'll just pick the latter option. We can revisit this concept later if necessary. Cc: Dave Hansen <[email protected]> Cc: Tilman Schmidt <[email protected]> Cc: Andrew Morton <[email protected]> Cc: Thomas Renninger <[email protected]> Cc: Eric Piel <[email protected]> Cc: Len Brown <[email protected]> Cc: Christoph Hellwig <[email protected]> Cc: Markus Gaugusch <[email protected]> Signed-off-by: Linus Torvalds <[email protected]>
josf · Mar 15, 2008 · 9a9e0d6 · 9a9e0d6
1 parent ce63645
commit 9a9e0d6
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Showing 7 changed files with 3 additions and 165 deletions.
diff --git a/Documentation/acpi/dsdt-override.txt b/Documentation/acpi/dsdt-override.txt
@@ -1,15 +1,7 @@
-Linux supports two methods of overriding the BIOS DSDT:
+Linux supports a method of overriding the BIOS DSDT:
 
 CONFIG_ACPI_CUSTOM_DSDT builds the image into the kernel.
 
-CONFIG_ACPI_CUSTOM_DSDT_INITRD adds the image to the initrd.
-
-When to use these methods is described in detail on the
+When to use this method is described in detail on the
 Linux/ACPI home page:
 http://www.lesswatts.org/projects/acpi/overridingDSDT.php
-
-Note that if both options are used, the DSDT supplied
-by the INITRD method takes precedence.
-
-Documentation/initramfs-add-dsdt.sh is provided for convenience
-for use with the CONFIG_ACPI_CUSTOM_DSDT_INITRD method.
diff --git a/Documentation/acpi/initramfs-add-dsdt.sh b/Documentation/acpi/initramfs-add-dsdt.sh
diff --git a/Documentation/kernel-parameters.txt b/Documentation/kernel-parameters.txt
@@ -177,9 +177,6 @@ and is between 256 and 4096 characters. It is defined in the file
 
 	acpi_no_auto_ssdt	[HW,ACPI] Disable automatic loading of SSDT
 
-	acpi_no_initrd_override	[KNL,ACPI]
-			Disable loading custom ACPI tables from the initramfs
-
 	acpi_os_name=	[HW,ACPI] Tell ACPI BIOS the name of the OS
 			Format: To spoof as Windows 98: ="Microsoft Windows"
 

diff --git a/drivers/acpi/Kconfig b/drivers/acpi/Kconfig
@@ -300,17 +300,6 @@ config ACPI_CUSTOM_DSDT
 	bool
 	default ACPI_CUSTOM_DSDT_FILE != ""
 
-config ACPI_CUSTOM_DSDT_INITRD
-	bool "Read Custom DSDT from initramfs"
-	depends on BLK_DEV_INITRD
-	default n
-	help
-	  This option supports a custom DSDT by optionally loading it from initrd.
-	  See Documentation/acpi/dsdt-override.txt
-
-	  If you are not using this feature now, but may use it later,
-	  it is safe to say Y here.
-
 config ACPI_BLACKLIST_YEAR
 	int "Disable ACPI for systems before Jan 1st this year" if X86_32
 	default 0

diff --git a/drivers/acpi/osl.c b/drivers/acpi/osl.c
@@ -91,10 +91,6 @@ static DEFINE_SPINLOCK(acpi_res_lock);
 #define	OSI_STRING_LENGTH_MAX 64	/* arbitrary */
 static char osi_additional_string[OSI_STRING_LENGTH_MAX];
 
-#ifdef CONFIG_ACPI_CUSTOM_DSDT_INITRD
-static int acpi_no_initrd_override;
-#endif
-
 /*
  * "Ode to _OSI(Linux)"
  *
@@ -324,67 +320,6 @@ acpi_os_predefined_override(const struct acpi_predefined_names *init_val,
 	return AE_OK;
 }
 
-#ifdef CONFIG_ACPI_CUSTOM_DSDT_INITRD
-static struct acpi_table_header *acpi_find_dsdt_initrd(void)
-{
-	struct file *firmware_file;
-	mm_segment_t oldfs;
-	unsigned long len, len2;
-	struct acpi_table_header *dsdt_buffer, *ret = NULL;
-	struct kstat stat;
-	char *ramfs_dsdt_name = "/DSDT.aml";
-
-	printk(KERN_INFO PREFIX "Checking initramfs for custom DSDT\n");
-
-	/*
-	 * Never do this at home, only the user-space is allowed to open a file.
-	 * The clean way would be to use the firmware loader.
-	 * But this code must be run before there is any userspace available.
-	 * A static/init firmware infrastructure doesn't exist yet...
-	 */
-	if (vfs_stat(ramfs_dsdt_name, &stat) < 0)
-		return ret;
-
-	len = stat.size;
-	/* check especially against empty files */
-	if (len <= 4) {
-		printk(KERN_ERR PREFIX "Failed: DSDT only %lu bytes.\n", len);
-		return ret;
-	}
-
-	firmware_file = filp_open(ramfs_dsdt_name, O_RDONLY, 0);
-	if (IS_ERR(firmware_file)) {
-		printk(KERN_ERR PREFIX "Failed to open %s.\n", ramfs_dsdt_name);
-		return ret;
-	}
-
-	dsdt_buffer = kmalloc(len, GFP_ATOMIC);
-	if (!dsdt_buffer) {
-		printk(KERN_ERR PREFIX "Failed to allocate %lu bytes.\n", len);
-		goto err;
-	}
-
-	oldfs = get_fs();
-	set_fs(KERNEL_DS);
-	len2 = vfs_read(firmware_file, (char __user *)dsdt_buffer, len,
-		&firmware_file->f_pos);
-	set_fs(oldfs);
-	if (len2 < len) {
-		printk(KERN_ERR PREFIX "Failed to read %lu bytes from %s.\n",
-			len, ramfs_dsdt_name);
-		ACPI_FREE(dsdt_buffer);
-		goto err;
-	}
-
-	printk(KERN_INFO PREFIX "Found %lu byte DSDT in %s.\n",
-			len, ramfs_dsdt_name);
-	ret = dsdt_buffer;
-err:
-	filp_close(firmware_file, NULL);
-	return ret;
-}
-#endif
-
 acpi_status
 acpi_os_table_override(struct acpi_table_header * existing_table,
 		       struct acpi_table_header ** new_table)
@@ -397,16 +332,6 @@ acpi_os_table_override(struct acpi_table_header * existing_table,
 #ifdef CONFIG_ACPI_CUSTOM_DSDT
 	if (strncmp(existing_table->signature, "DSDT", 4) == 0)
 		*new_table = (struct acpi_table_header *)AmlCode;
-#endif
-#ifdef CONFIG_ACPI_CUSTOM_DSDT_INITRD
-	if ((strncmp(existing_table->signature, "DSDT", 4) == 0) &&
-	    !acpi_no_initrd_override) {
-		struct acpi_table_header *initrd_table;
-
-		initrd_table = acpi_find_dsdt_initrd();
-		if (initrd_table)
-			*new_table = initrd_table;
-	}
 #endif
 	if (*new_table != NULL) {
 		printk(KERN_WARNING PREFIX "Override [%4.4s-%8.8s], "
@@ -418,15 +343,6 @@ acpi_os_table_override(struct acpi_table_header * existing_table,
 	return AE_OK;
 }
 
-#ifdef CONFIG_ACPI_CUSTOM_DSDT_INITRD
-static int __init acpi_no_initrd_override_setup(char *s)
-{
-	acpi_no_initrd_override = 1;
-	return 1;
-}
-__setup("acpi_no_initrd_override", acpi_no_initrd_override_setup);
-#endif
-
 static irqreturn_t acpi_irq(int irq, void *dev_id)
 {
 	u32 handled;

diff --git a/init/initramfs.c b/init/initramfs.c
@@ -538,7 +538,7 @@ static void __init free_initrd(void)
 	initrd_end = 0;
 }
 
-int __init populate_rootfs(void)
+static int __init populate_rootfs(void)
 {
 	char *err = unpack_to_rootfs(__initramfs_start,
 			 __initramfs_end - __initramfs_start, 0);
@@ -577,10 +577,4 @@ int __init populate_rootfs(void)
 	}
 	return 0;
 }
-#ifndef CONFIG_ACPI_CUSTOM_DSDT_INITRD
-/*
- * if this option is enabled, populate_rootfs() is called _earlier_ in the
- * boot sequence. This insures that the ACPI initialisation can find the file.
- */
 rootfs_initcall(populate_rootfs);
-#endif
diff --git a/init/main.c b/init/main.c
@@ -102,12 +102,6 @@ static inline void mark_rodata_ro(void) { }
 extern void tc_init(void);
 #endif
 
-#ifdef CONFIG_ACPI_CUSTOM_DSDT_INITRD
-extern int populate_rootfs(void);
-#else
-static inline void populate_rootfs(void) {}
-#endif
-
 enum system_states system_state;
 EXPORT_SYMBOL(system_state);
 
@@ -650,7 +644,6 @@ asmlinkage void __init start_kernel(void)
 
 	check_bugs();
 
-	populate_rootfs(); /* For DSDT override from initramfs */
 	acpi_early_init(); /* before LAPIC and SMP init */
 
 	/* Do the rest non-__init'ed, we're now alive */