-#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
-