Boot protocol changes

diff -r cff7afab3bac arch/i386/kernel/asm-offsets.c
@@ -15,6 +15,7 @@
 #include <asm/fixmap.h>
 #include <asm/processor.h>
 #include <asm/thread_info.h>
+#include <asm/bootparam.h>
 #include <asm/elf.h>
 
 #include <xen/interface/xen.h>

@@ -145,4 +146,10 @@ void foo(void)
 	OFFSET(LGUEST_PAGES_regs_errcode, lguest_pages, regs.errcode);
 	OFFSET(LGUEST_PAGES_regs, lguest_pages, regs);
 #endif
+
+	BLANK();
+	OFFSET(BP_scratch, boot_params, scratch);
+	OFFSET(BP_loadflags, boot_params, hdr.loadflags);
+	OFFSET(BP_hardware_subarch, boot_params, hdr.hardware_subarch);
+	OFFSET(BP_version, boot_params, hdr.version);
 }

diff -r cff7afab3bac include/asm-i386/bootparam.h
@@ -25,8 +25,9 @@ struct setup_header {
 	u16	kernel_version;
 	u8	type_of_loader;
 	u8	loadflags;
-#define LOADED_HIGH	0x01
-#define CAN_USE_HEAP	0x80
+#define LOADED_HIGH	(1<<0)
+#define KEEP_SEGMENTS	(1<<6)
+#define CAN_USE_HEAP	(1<<7)
 	u16	setup_move_size;
 	u32	code32_start;
 	u32	ramdisk_image;

@@ -38,6 +39,10 @@ struct setup_header {
 	u32	initrd_addr_max;
 	u32	kernel_alignment;
 	u8	relocatable_kernel;
+	u8	_pad2[3];
+	u32	cmdline_size;
+	u32	hardware_subarch;
+	u64	hardware_subarch_data;
 } __attribute__((packed));
 
 struct sys_desc_table {

@@ -34,6 +34,12 @@
   name:
 #endif
 
+#ifndef WEAK
+#define WEAK(name)	   \
+	.weak name;	   \
+	name:
+#endif
+
 #define KPROBE_ENTRY(name) \
   .pushsection .kprobes.text, "ax"; \
   ENTRY(name)

diff -r 5d471e4c931d arch/i386/boot/compressed/misc.c
@@ -246,6 +246,9 @@ static void putstr(const char *s)
 {
 	int x,y,pos;
 	char c;
+
+	if (RM_SCREEN_INFO.orig_video_mode == 0 && lines == 0 && cols == 0)
+		return;
 
 	x = RM_SCREEN_INFO.orig_x;
 	y = RM_SCREEN_INFO.orig_y;

diff -r 2fdc577cfe5c Documentation/lguest/lguest.c
@@ -251,23 +251,6 @@ static void *get_pages(unsigned int num)
 	return addr;
 }
 
-/* To find out where to start we look for the magic Guest string, which marks
- * the code we see in lguest_asm.S.  This is a hack which we are currently
- * plotting to replace with the normal Linux entry point. */
-static unsigned long entry_point(const void *start, const void *end)
-{
-	const void *p;
-
-	/* The scan gives us the physical starting address.  We boot with
-	 * pagetables set up with virtual and physical the same, so that's
-	 * OK. */
-	for (p = start; p < end; p++)
-		if (memcmp(p, "GenuineLguest", strlen("GenuineLguest")) == 0)
-			return to_guest_phys(p + strlen("GenuineLguest"));
-
-	errx(1, "Is this image a genuine lguest?");
-}
-
 /* This routine is used to load the kernel or initrd.  It tries mmap, but if
  * that fails (Plan 9's kernel file isn't nicely aligned on page boundaries),
  * it falls back to reading the memory in. */

@@ -303,7 +286,6 @@ static void map_at(int fd, void *addr, u
  * We return the starting address. */
 static unsigned long map_elf(int elf_fd, const Elf32_Ehdr *ehdr)
 {
-	void *start = (void *)-1, *end = NULL;
 	Elf32_Phdr phdr[ehdr->e_phnum];
 	unsigned int i;
 

@@ -335,19 +317,13 @@ static unsigned long map_elf(int elf_fd,
 		verbose("Section %i: size %i addr %p\n",
 			i, phdr[i].p_memsz, (void *)phdr[i].p_paddr);
 
-		/* We track the first and last address we mapped, so we can
-		 * tell entry_point() where to scan. */
-		if (from_guest_phys(phdr[i].p_paddr) < start)
-			start = from_guest_phys(phdr[i].p_paddr);
-		if (from_guest_phys(phdr[i].p_paddr) + phdr[i].p_filesz > end)
-			end=from_guest_phys(phdr[i].p_paddr)+phdr[i].p_filesz;
-
 		/* We map this section of the file at its physical address. */
 		map_at(elf_fd, from_guest_phys(phdr[i].p_paddr),
 		       phdr[i].p_offset, phdr[i].p_filesz);
 	}
 
-	return entry_point(start, end);
+	/* The entry point is given in the ELF header. */
+	return ehdr->e_entry;
 }
 
 /*L:160 Unfortunately the entire ELF image isn't compressed: the segments

@@ -374,7 +350,8 @@ static unsigned long unpack_bzimage(int 
 
 	verbose("Unpacked size %i addr %p\n", len, img);
 
-	return entry_point(img, img + len);
+	/* The entry point for a bzImage is always the first byte */
+	return (unsigned long)img;
 }
 
 /*L:150 A bzImage, unlike an ELF file, is not meant to be loaded.  You're

@@ -1684,8 +1661,15 @@ int main(int argc, char *argv[])
 	*(u32 *)(boot + 0x228) = 4096;
 	concat(boot + 4096, argv+optind+2);
 
-	/* The guest type value of "1" tells the Guest it's under lguest. */
-	*(int *)(boot + 0x23c) = 1;
+	/* Boot protocol version: 2.07 supports the fields for lguest. */
+	*(u16 *)(boot + 0x206) = 0x207;
+
+	/* The hardware_subarch value of "1" tells the Guest it's an lguest. */
+	*(u32 *)(boot + 0x23c) = 1;
+
+	/* Set bit 6 of the loadflags (aka. KEEP_SEGMENTS) so the entry path
+	 * does not ttry to reload segment registers. */
+	*(u8 *)(boot + 0x211) |= (1 << 6);
 
 	/* We tell the kernel to initialize the Guest: this returns the open
 	 * /dev/lguest file descriptor. */

diff -r 2fdc577cfe5c arch/i386/lguest/boot.c
@@ -938,18 +938,8 @@ static unsigned lguest_patch(u8 type, u1
 /*G:030 Once we get to lguest_init(), we know we're a Guest.  The paravirt_ops
  * structure in the kernel provides a single point for (almost) every routine
  * we have to override to avoid privileged instructions. */
-__init void lguest_init(void *boot)
-{
-	/* Copy boot parameters first: the Launcher put the physical location
-	 * in %esi, and head.S converted that to a virtual address and handed
-	 * it to us.  We use "__memcpy" because "memcpy" sometimes tries to do
-	 * tricky things to go faster, and we're not ready for that. */
-	__memcpy(&boot_params, boot, PARAM_SIZE);
-	/* The boot parameters also tell us where the command-line is: save
-	 * that, too. */
-	__memcpy(boot_command_line, __va(boot_params.hdr.cmd_line_ptr),
-	       COMMAND_LINE_SIZE);
-
+__init void lguest_init(void)
+{
 	/* We're under lguest, paravirt is enabled, and we're running at
 	 * privilege level 1, not 0 as normal. */
 	paravirt_ops.name = "lguest";

@@ -1018,11 +1008,6 @@ __init void lguest_init(void *boot)
 	 * the normal data segment to get through booting. */
 	asm volatile ("mov %0, %%fs" : : "r" (__KERNEL_DS) : "memory");
 
-	/* Clear the part of the kernel data which is expected to be zero.
-	 * Normally it will be anyway, but if we're loading from a bzImage with
-	 * CONFIG_RELOCATALE=y, the relocations will be sitting here. */
-	memset(__bss_start, 0, __bss_stop - __bss_start);
-
 	/* The Host uses the top of the Guest's virtual address space for the
 	 * Host<->Guest Switcher, and it tells us how much it needs in
 	 * lguest_data.reserve_mem, set up on the LGUEST_INIT hypercall. */

diff -r b0480fd71a72 Documentation/lguest/lguest.c
@@ -326,74 +326,39 @@ static unsigned long map_elf(int elf_fd,
 	return ehdr->e_entry;
 }
 
-/*L:160 Unfortunately the entire ELF image isn't compressed: the segments
- * which need loading are extracted and compressed raw.  This denies us the
- * information we need to make a fully-general loader. */
-static unsigned long unpack_bzimage(int fd)
-{
-	gzFile f;
-	int ret, len = 0;
-	/* A bzImage always gets loaded at physical address 1M.  This is
-	 * actually configurable as CONFIG_PHYSICAL_START, but as the comment
-	 * there says, "Don't change this unless you know what you are doing".
-	 * Indeed. */
-	void *img = from_guest_phys(0x100000);
-
-	/* gzdopen takes our file descriptor (carefully placed at the start of
-	 * the GZIP header we found) and returns a gzFile. */
-	f = gzdopen(fd, "rb");
-	/* We read it into memory in 64k chunks until we hit the end. */
-	while ((ret = gzread(f, img + len, 65536)) > 0)
-		len += ret;
-	if (ret < 0)
-		err(1, "reading image from bzImage");
-
-	verbose("Unpacked size %i addr %p\n", len, img);
-
-	/* The entry point for a bzImage is always the first byte */
-	return (unsigned long)img;
-}
-
 /*L:150 A bzImage, unlike an ELF file, is not meant to be loaded.  You're
- * supposed to jump into it and it will unpack itself.  We can't do that
- * because the Guest can't run the unpacking code, and adding features to
- * lguest kills puppies, so we don't want to.
- *
- * The bzImage is formed by putting the decompressing code in front of the
- * compressed kernel code.  So we can simple scan through it looking for the
- * first "gzip" header, and start decompressing from there. */
+ * supposed to jump into it and it will unpack itself.  We used to have to
+ * perform some hairy magic because the unpacking code scared me.
+ *
+ * Fortunately, Jeremy Fitzhardinge convinced me it wasn't that hard and wrote
+ * a small patch to jump over the tricky bits in the guest, so now we just read
+ * the funky header so we know where in the file to load, and away we go! */
 static unsigned long load_bzimage(int fd)
 {
-	unsigned char c;
-	int state = 0;
-
-	/* GZIP header is 0x1F 0x8B <method> <flags>... <compressed-by>. */
-	while (read(fd, &c, 1) == 1) {
-		switch (state) {
-		case 0:
-			if (c == 0x1F)
-				state++;
-			break;
-		case 1:
-			if (c == 0x8B)
-				state++;
-			else
-				state = 0;
-			break;
-		case 2 ... 8:
-			state++;
-			break;
-		case 9:
-			/* Seek back to the start of the gzip header. */
-			lseek(fd, -10, SEEK_CUR);
-			/* One final check: "compressed under UNIX". */
-			if (c != 0x03)
-				state = -1;
-			else
-				return unpack_bzimage(fd);
-		}
-	}
-	errx(1, "Could not find kernel in bzImage");
+	u8 hdr[1024];
+	int r;
+	/* Modern bzImages get loaded at 1M. */
+	void *p = from_guest_phys(0x100000);
+
+	/* Go back to the start of the file and read the header.  It should be
+	 * a Linux boot header (see Documentation/i386/boot.txt) */
+	lseek(fd, 0, SEEK_SET);
+	read(fd, hdr, sizeof(hdr));
+
+	/* At offset 0x202, we expect the magic "HdrS" */
+	if (memcmp(hdr + 0x202, "HdrS", 4) != 0)
+		errx(1, "This doesn't look like a bzImage to me");
+
+	/* The byte at 0x1F1 tells us how many extra sectors of
+	 * header: skip over them all. */
+	lseek(fd, (unsigned long)(hdr[0x1F1]+1) * 512, SEEK_SET);
+
+	/* Now read everything into memory. in nice big chunks. */
+	while ((r = read(fd, p, 65536)) > 0)
+		p += r;
+
+	/* Finally, 0x214 tells us where to start the kernel. */
+	return *(unsigned long *)&hdr[0x214];
 }
 
 /*L:140 Loading the kernel is easy when it's a "vmlinux", but most kernels

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diff -r 6bb527d113a8 include/asm-i386/e820.h
@@ -26,16 +26,17 @@
 #ifndef __ASSEMBLY__
 
 struct e820entry {
-	u64 addr;	/* start of memory segment */
-	u64 size;	/* size of memory segment */
-	u32 type;	/* type of memory segment */
+	__u64 addr;	/* start of memory segment */
+	__u64 size;	/* size of memory segment */
+	__u32 type;	/* type of memory segment */
 } __attribute__((packed));
 
 struct e820map {
-	u32 nr_map;
+	__u32 nr_map;
 	struct e820entry map[E820MAX];
 };
 
+#ifdef __KERNEL__
 extern struct e820map e820;
 
 extern int e820_all_mapped(unsigned long start, unsigned long end,

@@ -56,5 +57,5 @@ static inline void e820_mark_nosave_regi
 #endif
 
 #endif/*!__ASSEMBLY__*/
-
+#endif/*__KERNEL__*/
 #endif/*__E820_HEADER*/

diff -r 6bb527d113a8 include/asm-i386/ist.h
@@ -17,16 +17,16 @@
  */
 
 
-#ifdef __KERNEL__
-
 #include <linux/types.h>
 
 struct ist_info {
-	u32 signature;
-	u32 command;
-	u32 event;
-	u32 perf_level;
+	__u32 signature;
+	__u32 command;
+	__u32 event;
+	__u32 perf_level;
 };
+
+#ifdef __KERNEL__
 
 extern struct ist_info ist_info;
 

diff -r 6bb527d113a8 include/linux/apm_bios.h
@@ -16,28 +16,28 @@
  * General Public License for more details.
  */
 
+#include <linux/types.h>
+
+struct apm_bios_info {
+	__u16	version;
+	__u16	cseg;
+	__u32	offset;
+	__u16	cseg_16;
+	__u16	dseg;
+	__u16	flags;
+	__u16	cseg_len;
+	__u16	cseg_16_len;
+	__u16	dseg_len;
+};
+
+#ifdef __KERNEL__
+
 typedef unsigned short	apm_event_t;
 typedef unsigned short	apm_eventinfo_t;
-
-#ifdef __KERNEL__
-
-#include <linux/types.h>
 
 #define APM_CS		(GDT_ENTRY_APMBIOS_BASE * 8)
 #define APM_CS_16	(APM_CS + 8)
 #define APM_DS		(APM_CS_16 + 8)
-
-struct apm_bios_info {
-	u16	version;
-	u16	cseg;
-	u32	offset;
-	u16	cseg_16;
-	u16	dseg;
-	u16	flags;
-	u16	cseg_len;
-	u16	cseg_16_len;
-	u16	dseg_len;
-};
 
 /* Results of APM Installation Check */
 #define APM_16_BIT_SUPPORT	0x0001

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diff -r 6bb527d113a8 include/video/edid.h
@@ -1,17 +1,16 @@
 #ifndef __linux_video_edid_h__
 #define __linux_video_edid_h__
 
-#ifdef __KERNEL__
+#if !defined(__KERNEL__) || defined(CONFIG_X86)
 
-
-#ifdef CONFIG_X86
 struct edid_info {
 	unsigned char dummy[128];
 };
 
+#ifdef __KERNEL__
 extern struct edid_info edid_info;
-#endif /* CONFIG_X86 */
-
 #endif /* __KERNEL__ */
 
+#endif
+
 #endif /* __linux_video_edid_h__ */