mirror of
https://github.com/xcat2/xNBA.git
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[bzimage] Support old (pre-2.00 bootloader) Linux kernel formats
This allows gPXE to load memtest86, which is packaged as an old kernel. Split all code that directly touches the kernel headers out into bzimage_parse_header() and bzimage_update_header(), to reduce code size and offset the cost of supporting older kernels. Total cost of this feature: 11 bytes (uncompressed).
This commit is contained in:
Michael Brown
parent
a436dc4014
commit
abc13af070
@ -42,9 +42,11 @@ FEATURE ( FEATURE_IMAGE, "bzImage", DHCP_EB_FEATURE_BZIMAGE, 1 );
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struct image_type bzimage_image_type __image_type ( PROBE_NORMAL );
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/**
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* bzImage load context
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* bzImage context
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*/
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struct bzimage_load_context {
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struct bzimage_context {
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/** Boot protocol version */
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unsigned int version;
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/** Real-mode kernel portion load segment address */
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unsigned int rm_kernel_seg;
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/** Real-mode kernel portion load address */
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@ -55,28 +57,14 @@ struct bzimage_load_context {
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size_t rm_heap;
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/** Command line (offset from rm_kernel) */
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size_t rm_cmdline;
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/** Command line maximum length */
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size_t cmdline_size;
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/** Real-mode kernel portion total memory size */
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size_t rm_memsz;
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/** Non-real-mode kernel portion load address */
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userptr_t pm_kernel;
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/** Non-real-mode kernel portion file and memory size */
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size_t pm_sz;
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};
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/**
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* bzImage execution context
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*/
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struct bzimage_exec_context {
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/** Real-mode kernel portion load segment address */
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unsigned int rm_kernel_seg;
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/** Real-mode kernel portion load address */
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userptr_t rm_kernel;
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/** Real-mode heap top (offset from rm_kernel) */
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size_t rm_heap;
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/** Command line (offset from rm_kernel) */
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size_t rm_cmdline;
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/** Command line maximum length */
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size_t cmdline_size;
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/** Video mode */
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unsigned int vid_mode;
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/** Memory limit */
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@ -85,18 +73,178 @@ struct bzimage_exec_context {
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physaddr_t ramdisk_image;
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/** Initrd size */
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physaddr_t ramdisk_size;
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/** Command line magic block */
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struct bzimage_cmdline cmdline_magic;
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/** bzImage header */
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struct bzimage_header bzhdr;
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};
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/**
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* Parse bzImage header
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*
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* @v image bzImage file
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* @v bzimg bzImage context
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* @v src bzImage to parse
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* @ret rc Return status code
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*/
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static int bzimage_parse_header ( struct image *image,
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struct bzimage_context *bzimg,
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userptr_t src ) {
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unsigned int syssize;
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int is_bzimage;
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/* Sanity check */
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if ( image->len < ( BZI_HDR_OFFSET + sizeof ( bzimg->bzhdr ) ) ) {
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DBGC ( image, "bzImage %p too short for kernel header\n",
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image );
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return -ENOEXEC;
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}
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/* Read in header structures */
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memset ( bzimg, 0, sizeof ( *bzimg ) );
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copy_from_user ( &bzimg->cmdline_magic, src, BZI_CMDLINE_OFFSET,
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sizeof ( bzimg->cmdline_magic ) );
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copy_from_user ( &bzimg->bzhdr, src, BZI_HDR_OFFSET,
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sizeof ( bzimg->bzhdr ) );
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/* Calculate size of real-mode portion */
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bzimg->rm_filesz =
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( ( bzimg->bzhdr.setup_sects ? bzimg->bzhdr.setup_sects : 4 ) + 1 ) << 9;
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if ( bzimg->rm_filesz > image->len ) {
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DBGC ( image, "bzImage %p too short for %zd byte of setup\n",
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image, bzimg->rm_filesz );
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return -ENOEXEC;
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}
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bzimg->rm_memsz = BZI_ASSUMED_RM_SIZE;
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/* Calculate size of protected-mode portion */
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bzimg->pm_sz = ( image->len - bzimg->rm_filesz );
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syssize = ( ( bzimg->pm_sz + 15 ) / 16 );
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/* Check for signatures and determine version */
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if ( bzimg->bzhdr.boot_flag != BZI_BOOT_FLAG ) {
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DBGC ( image, "bzImage %p missing 55AA signature\n", image );
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return -ENOEXEC;
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}
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if ( bzimg->bzhdr.header == BZI_SIGNATURE ) {
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/* 2.00+ */
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bzimg->version = bzimg->bzhdr.version;
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} else {
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/* Pre-2.00. Check that the syssize field is correct,
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* as a guard against accepting arbitrary binary data,
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* since the 55AA check is pretty lax. Note that the
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* syssize field is unreliable for protocols between
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* 2.00 and 2.03 inclusive, so we should not always
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* check this field.
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*/
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bzimg->version = 0x0100;
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if ( bzimg->bzhdr.syssize != syssize ) {
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DBGC ( image, "bzImage %p bad syssize %x (expected "
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"%x)\n", image, bzimg->bzhdr.syssize, syssize );
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return -ENOEXEC;
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}
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}
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/* Determine image type */
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is_bzimage = ( ( bzimg->version >= 0x0200 ) ?
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( bzimg->bzhdr.loadflags & BZI_LOAD_HIGH ) : 0 );
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/* Calculate load address of real-mode portion */
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bzimg->rm_kernel_seg = ( is_bzimage ? 0x1000 : 0x9000 );
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bzimg->rm_kernel = real_to_user ( bzimg->rm_kernel_seg, 0 );
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/* Allow space for the stack and heap */
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bzimg->rm_memsz += BZI_STACK_SIZE;
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bzimg->rm_heap = bzimg->rm_memsz;
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/* Allow space for the command line */
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bzimg->rm_cmdline = bzimg->rm_memsz;
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bzimg->rm_memsz += BZI_CMDLINE_SIZE;
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/* Calculate load address of protected-mode portion */
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bzimg->pm_kernel = phys_to_user ( is_bzimage ? BZI_LOAD_HIGH_ADDR
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: BZI_LOAD_LOW_ADDR );
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/* Extract video mode */
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bzimg->vid_mode = bzimg->bzhdr.vid_mode;
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/* Extract memory limit */
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bzimg->mem_limit = ( ( bzimg->version >= 0x0203 ) ?
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bzimg->bzhdr.initrd_addr_max : BZI_INITRD_MAX );
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/* Extract command line size */
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bzimg->cmdline_size = ( ( bzimg->version >= 0x0206 ) ?
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bzimg->bzhdr.cmdline_size : BZI_CMDLINE_SIZE );
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DBGC ( image, "bzImage %p version %04x RM %#lx+%#zx PM %#lx+%#zx "
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"cmdlen %zd\n", image, bzimg->version,
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user_to_phys ( bzimg->rm_kernel, 0 ), bzimg->rm_filesz,
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user_to_phys ( bzimg->pm_kernel, 0 ), bzimg->pm_sz,
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bzimg->cmdline_size );
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return 0;
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}
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/**
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* Update bzImage header in loaded kernel
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*
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* @v image bzImage file
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* @v bzimg bzImage context
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* @v dst bzImage to update
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*/
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static void bzimage_update_header ( struct image *image,
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struct bzimage_context *bzimg,
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userptr_t dst ) {
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/* Set loader type */
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if ( bzimg->version >= 0x0200 )
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bzimg->bzhdr.type_of_loader = BZI_LOADER_TYPE_GPXE;
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/* Set heap end pointer */
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if ( bzimg->version >= 0x0201 ) {
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bzimg->bzhdr.heap_end_ptr = ( bzimg->rm_heap - 0x200 );
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bzimg->bzhdr.loadflags |= BZI_CAN_USE_HEAP;
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}
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/* Set command line */
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if ( bzimg->version >= 0x0202 ) {
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bzimg->bzhdr.cmd_line_ptr = user_to_phys ( bzimg->rm_kernel,
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bzimg->rm_cmdline );
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} else {
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bzimg->cmdline_magic.magic = BZI_CMDLINE_MAGIC;
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bzimg->cmdline_magic.offset = bzimg->rm_cmdline;
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bzimg->bzhdr.setup_move_size = bzimg->rm_memsz;
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}
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/* Set video mode */
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bzimg->bzhdr.vid_mode = bzimg->vid_mode;
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/* Set initrd address */
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if ( bzimg->version >= 0x0200 ) {
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bzimg->bzhdr.ramdisk_image = bzimg->ramdisk_image;
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bzimg->bzhdr.ramdisk_size = bzimg->ramdisk_size;
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}
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/* Write out header structures */
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copy_to_user ( dst, BZI_CMDLINE_OFFSET, &bzimg->cmdline_magic,
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sizeof ( bzimg->cmdline_magic ) );
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copy_to_user ( dst, BZI_HDR_OFFSET, &bzimg->bzhdr,
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sizeof ( bzimg->bzhdr ) );
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DBGC ( image, "bzImage %p vidmode %d\n", image, bzimg->vid_mode );
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}
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/**
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* Parse kernel command line for bootloader parameters
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*
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* @v image bzImage file
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* @v exec_ctx Execution context
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* @v bzimg bzImage context
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* @v cmdline Kernel command line
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* @ret rc Return status code
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*/
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static int bzimage_parse_cmdline ( struct image *image,
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struct bzimage_exec_context *exec_ctx,
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struct bzimage_context *bzimg,
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const char *cmdline ) {
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char *vga;
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char *mem;
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@ -105,13 +253,13 @@ static int bzimage_parse_cmdline ( struct image *image,
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if ( ( vga = strstr ( cmdline, "vga=" ) ) ) {
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vga += 4;
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if ( strcmp ( vga, "normal" ) == 0 ) {
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exec_ctx->vid_mode = BZI_VID_MODE_NORMAL;
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bzimg->vid_mode = BZI_VID_MODE_NORMAL;
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} else if ( strcmp ( vga, "ext" ) == 0 ) {
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exec_ctx->vid_mode = BZI_VID_MODE_EXT;
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bzimg->vid_mode = BZI_VID_MODE_EXT;
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} else if ( strcmp ( vga, "ask" ) == 0 ) {
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exec_ctx->vid_mode = BZI_VID_MODE_ASK;
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bzimg->vid_mode = BZI_VID_MODE_ASK;
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} else {
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exec_ctx->vid_mode = strtoul ( vga, &vga, 0 );
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bzimg->vid_mode = strtoul ( vga, &vga, 0 );
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if ( *vga && ( *vga != ' ' ) ) {
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DBGC ( image, "bzImage %p strange \"vga=\""
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"terminator '%c'\n", image, *vga );
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@ -122,17 +270,17 @@ static int bzimage_parse_cmdline ( struct image *image,
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/* Look for "mem=" */
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if ( ( mem = strstr ( cmdline, "mem=" ) ) ) {
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mem += 4;
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exec_ctx->mem_limit = strtoul ( mem, &mem, 0 );
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bzimg->mem_limit = strtoul ( mem, &mem, 0 );
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switch ( *mem ) {
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case 'G':
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case 'g':
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exec_ctx->mem_limit <<= 10;
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bzimg->mem_limit <<= 10;
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case 'M':
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case 'm':
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exec_ctx->mem_limit <<= 10;
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bzimg->mem_limit <<= 10;
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case 'K':
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case 'k':
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exec_ctx->mem_limit <<= 10;
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bzimg->mem_limit <<= 10;
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break;
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case '\0':
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case ' ':
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@ -142,7 +290,7 @@ static int bzimage_parse_cmdline ( struct image *image,
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"terminator '%c'\n", image, *mem );
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break;
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}
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exec_ctx->mem_limit -= 1;
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bzimg->mem_limit -= 1;
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}
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return 0;
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@ -152,20 +300,20 @@ static int bzimage_parse_cmdline ( struct image *image,
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* Set command line
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*
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* @v image bzImage image
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* @v exec_ctx Execution context
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* @v bzimg bzImage context
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* @v cmdline Kernel command line
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* @ret rc Return status code
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*/
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static int bzimage_set_cmdline ( struct image *image,
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struct bzimage_exec_context *exec_ctx,
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struct bzimage_context *bzimg,
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const char *cmdline ) {
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size_t cmdline_len;
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/* Copy command line down to real-mode portion */
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cmdline_len = ( strlen ( cmdline ) + 1 );
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if ( cmdline_len > exec_ctx->cmdline_size )
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cmdline_len = exec_ctx->cmdline_size;
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copy_to_user ( exec_ctx->rm_kernel, exec_ctx->rm_cmdline,
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if ( cmdline_len > bzimg->cmdline_size )
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cmdline_len = bzimg->cmdline_size;
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copy_to_user ( bzimg->rm_kernel, bzimg->rm_cmdline,
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cmdline, cmdline_len );
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DBGC ( image, "bzImage %p command line \"%s\"\n", image, cmdline );
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@ -217,14 +365,16 @@ static size_t bzimage_load_initrd ( struct image *image,
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}
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/* Copy in initrd image body */
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if ( address )
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memcpy_user ( address, offset, initrd->data, 0, initrd->len );
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offset += initrd->len;
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if ( address ) {
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DBGC ( image, "bzImage %p has initrd %p at [%lx,%lx)\n",
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image, initrd, address, ( address + offset ) );
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memcpy_user ( address, offset, initrd->data, 0,
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initrd->len );
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image, initrd, user_to_phys ( address, 0 ),
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user_to_phys ( address, offset ) );
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}
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offset += initrd->len;
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/* Round up to 4-byte boundary */
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offset = ( ( offset + 0x03 ) & ~0x03 );
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return offset;
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}
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@ -233,20 +383,19 @@ static size_t bzimage_load_initrd ( struct image *image,
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* Load initrds, if any
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*
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* @v image bzImage image
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* @v exec_ctx Execution context
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* @v bzimg bzImage context
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* @ret rc Return status code
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*/
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static int bzimage_load_initrds ( struct image *image,
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struct bzimage_exec_context *exec_ctx ) {
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struct bzimage_context *bzimg ) {
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struct image *initrd;
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size_t total_len = 0;
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physaddr_t address;
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int rc;
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/* Add up length of all initrd images */
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for_each_image ( initrd ) {
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for_each_image ( initrd )
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total_len += bzimage_load_initrd ( image, initrd, UNULL );
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}
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/* Give up if no initrd images found */
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if ( ! total_len )
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@ -268,7 +417,7 @@ static int bzimage_load_initrds ( struct image *image,
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return -ENOBUFS;
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}
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/* Check that we are within the kernel's range */
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if ( ( address + total_len - 1 ) > exec_ctx->mem_limit )
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if ( ( address + total_len - 1 ) > bzimg->mem_limit )
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continue;
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/* Prepare and verify segment */
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if ( ( rc = prep_segment ( phys_to_user ( address ), 0,
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@ -279,8 +428,8 @@ static int bzimage_load_initrds ( struct image *image,
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}
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/* Record initrd location */
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exec_ctx->ramdisk_image = address;
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exec_ctx->ramdisk_size = total_len;
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bzimg->ramdisk_image = address;
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bzimg->ramdisk_size = total_len;
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/* Construct initrd */
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DBGC ( image, "bzImage %p constructing initrd at [%lx,%lx)\n",
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@ -300,60 +449,37 @@ static int bzimage_load_initrds ( struct image *image,
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* @ret rc Return status code
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*/
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static int bzimage_exec ( struct image *image ) {
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struct bzimage_exec_context exec_ctx;
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struct bzimage_header bzhdr;
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struct bzimage_context bzimg;
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const char *cmdline = ( image->cmdline ? image->cmdline : "" );
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int rc;
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/* Initialise context */
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memset ( &exec_ctx, 0, sizeof ( exec_ctx ) );
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/* Retrieve kernel header */
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exec_ctx.rm_kernel_seg = image->priv.ul;
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exec_ctx.rm_kernel = real_to_user ( exec_ctx.rm_kernel_seg, 0 );
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copy_from_user ( &bzhdr, exec_ctx.rm_kernel, BZI_HDR_OFFSET,
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sizeof ( bzhdr ) );
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exec_ctx.rm_cmdline = exec_ctx.rm_heap =
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( bzhdr.heap_end_ptr + 0x200 );
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exec_ctx.vid_mode = bzhdr.vid_mode;
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if ( bzhdr.version >= 0x0203 ) {
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exec_ctx.mem_limit = bzhdr.initrd_addr_max;
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} else {
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exec_ctx.mem_limit = BZI_INITRD_MAX;
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}
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if ( bzhdr.version >= 0x0206 ) {
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exec_ctx.cmdline_size = bzhdr.cmdline_size;
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} else {
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exec_ctx.cmdline_size = BZI_CMDLINE_SIZE;
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}
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DBG ( "cmdline_size = %zd\n", exec_ctx.cmdline_size );
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/* Read and parse header from loaded kernel */
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if ( ( rc = bzimage_parse_header ( image, &bzimg,
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image->priv.user ) ) != 0 )
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return rc;
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assert ( bzimg.rm_kernel == image->priv.user );
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/* Parse command line for bootloader parameters */
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if ( ( rc = bzimage_parse_cmdline ( image, &exec_ctx, cmdline ) ) != 0)
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if ( ( rc = bzimage_parse_cmdline ( image, &bzimg, cmdline ) ) != 0)
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return rc;
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/* Store command line */
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if ( ( rc = bzimage_set_cmdline ( image, &exec_ctx, cmdline ) ) != 0 )
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if ( ( rc = bzimage_set_cmdline ( image, &bzimg, cmdline ) ) != 0 )
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return rc;
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/* Load any initrds */
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if ( ( rc = bzimage_load_initrds ( image, &exec_ctx ) ) != 0 )
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if ( ( rc = bzimage_load_initrds ( image, &bzimg ) ) != 0 )
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return rc;
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/* Update and store kernel header */
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bzhdr.vid_mode = exec_ctx.vid_mode;
|
||||
bzhdr.ramdisk_image = exec_ctx.ramdisk_image;
|
||||
bzhdr.ramdisk_size = exec_ctx.ramdisk_size;
|
||||
copy_to_user ( exec_ctx.rm_kernel, BZI_HDR_OFFSET, &bzhdr,
|
||||
sizeof ( bzhdr ) );
|
||||
/* Update kernel header */
|
||||
bzimage_update_header ( image, &bzimg, bzimg.rm_kernel );
|
||||
|
||||
/* Prepare for exiting */
|
||||
shutdown ( SHUTDOWN_BOOT );
|
||||
|
||||
DBGC ( image, "bzImage %p jumping to RM kernel at %04x:0000 "
|
||||
"(stack %04x:%04zx)\n", image,
|
||||
( exec_ctx.rm_kernel_seg + 0x20 ),
|
||||
exec_ctx.rm_kernel_seg, exec_ctx.rm_heap );
|
||||
"(stack %04x:%04zx)\n", image, ( bzimg.rm_kernel_seg + 0x20 ),
|
||||
bzimg.rm_kernel_seg, bzimg.rm_heap );
|
||||
|
||||
/* Jump to the kernel */
|
||||
__asm__ __volatile__ ( REAL_CODE ( "movw %w0, %%ds\n\t"
|
||||
@ -365,9 +491,9 @@ static int bzimage_exec ( struct image *image ) {
|
||||
"pushw %w2\n\t"
|
||||
"pushw $0\n\t"
|
||||
"lret\n\t" )
|
||||
: : "r" ( exec_ctx.rm_kernel_seg ),
|
||||
"r" ( exec_ctx.rm_heap ),
|
||||
"r" ( exec_ctx.rm_kernel_seg + 0x20 ) );
|
||||
: : "r" ( bzimg.rm_kernel_seg ),
|
||||
"r" ( bzimg.rm_heap ),
|
||||
"r" ( bzimg.rm_kernel_seg + 0x20 ) );
|
||||
|
||||
/* There is no way for the image to return, since we provide
|
||||
* no return address.
|
||||
@ -377,157 +503,6 @@ static int bzimage_exec ( struct image *image ) {
|
||||
return -ECANCELED; /* -EIMPOSSIBLE */
|
||||
}
|
||||
|
||||
/**
|
||||
* Load and parse bzImage header
|
||||
*
|
||||
* @v image bzImage file
|
||||
* @v load_ctx Load context
|
||||
* @v bzhdr Buffer for bzImage header
|
||||
* @ret rc Return status code
|
||||
*/
|
||||
static int bzimage_load_header ( struct image *image,
|
||||
struct bzimage_load_context *load_ctx,
|
||||
struct bzimage_header *bzhdr ) {
|
||||
|
||||
/* Sanity check */
|
||||
if ( image->len < ( BZI_HDR_OFFSET + sizeof ( *bzhdr ) ) ) {
|
||||
DBGC ( image, "bzImage %p too short for kernel header\n",
|
||||
image );
|
||||
return -ENOEXEC;
|
||||
}
|
||||
|
||||
/* Read and verify header */
|
||||
copy_from_user ( bzhdr, image->data, BZI_HDR_OFFSET,
|
||||
sizeof ( *bzhdr ) );
|
||||
if ( bzhdr->header != BZI_SIGNATURE ) {
|
||||
DBGC ( image, "bzImage %p bad signature %08x\n",
|
||||
image, bzhdr->header );
|
||||
return -ENOEXEC;
|
||||
}
|
||||
|
||||
/* We don't support ancient kernels */
|
||||
if ( bzhdr->version < 0x0200 ) {
|
||||
DBGC ( image, "bzImage %p version %04x not supported\n",
|
||||
image, bzhdr->version );
|
||||
return -ENOTSUP;
|
||||
}
|
||||
|
||||
/* Calculate load address and size of real-mode portion */
|
||||
load_ctx->rm_kernel_seg = ( ( bzhdr->loadflags & BZI_LOAD_HIGH ) ?
|
||||
0x1000 : /* 1000:0000 (bzImage) */
|
||||
0x9000 ); /* 9000:0000 (zImage) */
|
||||
load_ctx->rm_kernel = real_to_user ( load_ctx->rm_kernel_seg, 0 );
|
||||
load_ctx->rm_filesz =
|
||||
( ( bzhdr->setup_sects ? bzhdr->setup_sects : 4 ) + 1 ) << 9;
|
||||
load_ctx->rm_memsz = BZI_ASSUMED_RM_SIZE;
|
||||
if ( load_ctx->rm_filesz > image->len ) {
|
||||
DBGC ( image, "bzImage %p too short for %zd byte of setup\n",
|
||||
image, load_ctx->rm_filesz );
|
||||
return -ENOEXEC;
|
||||
}
|
||||
|
||||
/* Calculate load address and size of non-real-mode portion */
|
||||
load_ctx->pm_kernel = ( ( bzhdr->loadflags & BZI_LOAD_HIGH ) ?
|
||||
phys_to_user ( BZI_LOAD_HIGH_ADDR ) :
|
||||
phys_to_user ( BZI_LOAD_LOW_ADDR ) );
|
||||
load_ctx->pm_sz = ( image->len - load_ctx->rm_filesz );
|
||||
|
||||
DBGC ( image, "bzImage %p version %04x RM %#zx bytes PM %#zx bytes\n",
|
||||
image, bzhdr->version, load_ctx->rm_filesz, load_ctx->pm_sz );
|
||||
return 0;
|
||||
}
|
||||
|
||||
/**
|
||||
* Load real-mode portion of bzImage
|
||||
*
|
||||
* @v image bzImage file
|
||||
* @v load_ctx Load context
|
||||
* @ret rc Return status code
|
||||
*/
|
||||
static int bzimage_load_real ( struct image *image,
|
||||
struct bzimage_load_context *load_ctx ) {
|
||||
int rc;
|
||||
|
||||
/* Allow space for the stack and heap */
|
||||
load_ctx->rm_memsz += BZI_STACK_SIZE;
|
||||
load_ctx->rm_heap = load_ctx->rm_memsz;
|
||||
|
||||
/* Allow space for the command line */
|
||||
load_ctx->rm_cmdline = load_ctx->rm_memsz;
|
||||
load_ctx->rm_memsz += BZI_CMDLINE_SIZE;
|
||||
|
||||
/* Prepare, verify, and load the real-mode segment */
|
||||
if ( ( rc = prep_segment ( load_ctx->rm_kernel, load_ctx->rm_filesz,
|
||||
load_ctx->rm_memsz ) ) != 0 ) {
|
||||
DBGC ( image, "bzImage %p could not prepare RM segment: %s\n",
|
||||
image, strerror ( rc ) );
|
||||
return rc;
|
||||
}
|
||||
memcpy_user ( load_ctx->rm_kernel, 0, image->data, 0,
|
||||
load_ctx->rm_filesz );
|
||||
|
||||
return 0;
|
||||
}
|
||||
|
||||
/**
|
||||
* Load non-real-mode portion of bzImage
|
||||
*
|
||||
* @v image bzImage file
|
||||
* @v load_ctx Load context
|
||||
* @ret rc Return status code
|
||||
*/
|
||||
static int bzimage_load_non_real ( struct image *image,
|
||||
struct bzimage_load_context *load_ctx ) {
|
||||
int rc;
|
||||
|
||||
/* Prepare, verify and load the non-real-mode segment */
|
||||
if ( ( rc = prep_segment ( load_ctx->pm_kernel, load_ctx->pm_sz,
|
||||
load_ctx->pm_sz ) ) != 0 ) {
|
||||
DBGC ( image, "bzImage %p could not prepare PM segment: %s\n",
|
||||
image, strerror ( rc ) );
|
||||
return rc;
|
||||
}
|
||||
memcpy_user ( load_ctx->pm_kernel, 0, image->data, load_ctx->rm_filesz,
|
||||
load_ctx->pm_sz );
|
||||
|
||||
return 0;
|
||||
}
|
||||
|
||||
/**
|
||||
* Update and store bzImage header
|
||||
*
|
||||
* @v image bzImage file
|
||||
* @v load_ctx Load context
|
||||
* @v bzhdr Original bzImage header
|
||||
* @ret rc Return status code
|
||||
*/
|
||||
static int bzimage_write_header ( struct image *image __unused,
|
||||
struct bzimage_load_context *load_ctx,
|
||||
struct bzimage_header *bzhdr ) {
|
||||
struct bzimage_cmdline cmdline;
|
||||
|
||||
/* Update the header and copy it into the loaded kernel */
|
||||
bzhdr->type_of_loader = BZI_LOADER_TYPE_GPXE;
|
||||
if ( bzhdr->version >= 0x0201 ) {
|
||||
bzhdr->heap_end_ptr = ( load_ctx->rm_heap - 0x200 );
|
||||
bzhdr->loadflags |= BZI_CAN_USE_HEAP;
|
||||
}
|
||||
if ( bzhdr->version >= 0x0202 ) {
|
||||
bzhdr->cmd_line_ptr = user_to_phys ( load_ctx->rm_kernel,
|
||||
load_ctx->rm_cmdline );
|
||||
} else {
|
||||
cmdline.magic = BZI_CMDLINE_MAGIC;
|
||||
cmdline.offset = load_ctx->rm_cmdline;
|
||||
copy_to_user ( load_ctx->rm_kernel, BZI_CMDLINE_OFFSET,
|
||||
&cmdline, sizeof ( cmdline ) );
|
||||
bzhdr->setup_move_size = load_ctx->rm_memsz;
|
||||
}
|
||||
copy_to_user ( load_ctx->rm_kernel, BZI_HDR_OFFSET,
|
||||
bzhdr, sizeof ( *bzhdr ) );
|
||||
|
||||
return 0;
|
||||
}
|
||||
|
||||
/**
|
||||
* Load bzImage image into memory
|
||||
*
|
||||
@ -535,35 +510,43 @@ static int bzimage_write_header ( struct image *image __unused,
|
||||
* @ret rc Return status code
|
||||
*/
|
||||
int bzimage_load ( struct image *image ) {
|
||||
struct bzimage_load_context load_ctx;
|
||||
struct bzimage_header bzhdr;
|
||||
struct bzimage_context bzimg;
|
||||
int rc;
|
||||
|
||||
/* Initialise context */
|
||||
memset ( &load_ctx, 0, sizeof ( load_ctx ) );
|
||||
|
||||
/* Load and verify header */
|
||||
if ( ( rc = bzimage_load_header ( image, &load_ctx, &bzhdr ) ) != 0 )
|
||||
/* Read and parse header from image */
|
||||
if ( ( rc = bzimage_parse_header ( image, &bzimg,
|
||||
image->data ) ) != 0 )
|
||||
return rc;
|
||||
|
||||
/* This is a bzImage image, valid or otherwise */
|
||||
if ( ! image->type )
|
||||
image->type = &bzimage_image_type;
|
||||
|
||||
/* Load real-mode portion */
|
||||
if ( ( rc = bzimage_load_real ( image, &load_ctx ) ) != 0 )
|
||||
/* Prepare segments */
|
||||
if ( ( rc = prep_segment ( bzimg.rm_kernel, bzimg.rm_filesz,
|
||||
bzimg.rm_memsz ) ) != 0 ) {
|
||||
DBGC ( image, "bzImage %p could not prepare RM segment: %s\n",
|
||||
image, strerror ( rc ) );
|
||||
return rc;
|
||||
}
|
||||
if ( ( rc = prep_segment ( bzimg.pm_kernel, bzimg.pm_sz,
|
||||
bzimg.pm_sz ) ) != 0 ) {
|
||||
DBGC ( image, "bzImage %p could not prepare PM segment: %s\n",
|
||||
image, strerror ( rc ) );
|
||||
return rc;
|
||||
}
|
||||
|
||||
/* Load non-real-mode portion */
|
||||
if ( ( rc = bzimage_load_non_real ( image, &load_ctx ) ) != 0 )
|
||||
return rc;
|
||||
/* Load segments */
|
||||
memcpy_user ( bzimg.rm_kernel, 0, image->data,
|
||||
0, bzimg.rm_filesz );
|
||||
memcpy_user ( bzimg.pm_kernel, 0, image->data,
|
||||
bzimg.rm_filesz, bzimg.pm_sz );
|
||||
|
||||
/* Update and write out header */
|
||||
if ( ( rc = bzimage_write_header ( image, &load_ctx, &bzhdr ) ) != 0 )
|
||||
return rc;
|
||||
bzimage_update_header ( image, &bzimg, bzimg.rm_kernel );
|
||||
|
||||
/* Record real-mode segment in image private data field */
|
||||
image->priv.ul = load_ctx.rm_kernel_seg;
|
||||
image->priv.user = bzimg.rm_kernel;
|
||||
|
||||
return 0;
|
||||
}
|
||||
|
||||
@ -75,6 +75,9 @@ struct bzimage_header {
|
||||
/** Offset of bzImage header within kernel image */
|
||||
#define BZI_HDR_OFFSET 0x1f1
|
||||
|
||||
/** bzImage boot flag value */
|
||||
#define BZI_BOOT_FLAG 0xaa55
|
||||
|
||||
/** bzImage magic signature value */
|
||||
#define BZI_SIGNATURE 0x53726448
|
||||
|
||||
|
||||
Loading…
x
Reference in New Issue
Block a user