diff mbox series

[02/11] x86 setup: per-arch bootmodule structure, headroom field

Message ID 20230701003132.2210306-3-christopher.w.clark@gmail.com (mailing list archive)
State New, archived
Headers show
Series v2: Boot modules for Hyperlaunch | expand

Commit Message

Christopher Clark July 1, 2023, 12:31 a.m. UTC 
Next step in incremental work towards adding a non-multiboot internal
representation of boot modules, converting the fields being accessed for
the startup calculations.

Add a new array of structs for per-boot-module state, though only
allocate space for a single array entry in this change since that is all
that is required for functionality modified in this patch: moving the
headroom field for the image decompression calculation into a new
per-arch boot module struct and then using it in x86 dom0 construction.

Introduces a per-arch header for x86 for arch-specific boot module
structures, and add a member to the common boot module structure for
access to it.

No functional change intended.

Signed-off-by: Christopher Clark <christopher.w.clark@gmail.com>
Signed-off-by: Daniel P. Smith <dpsmith@apertussolutions.com>

changes since v1:
- patch is a subset of v1 patches 2 and 3
---
 xen/arch/x86/bzimage.c              | 10 +++++-----
 xen/arch/x86/hvm/dom0_build.c       |  3 ++-
 xen/arch/x86/include/asm/bootinfo.h | 18 ++++++++++++++++++
 xen/arch/x86/include/asm/bzimage.h  |  2 +-
 xen/arch/x86/pv/dom0_build.c        |  3 ++-
 xen/arch/x86/setup.c                | 23 ++++++++++++++++-------
 xen/include/xen/bootinfo.h          | 11 +++++++++++
 7 files changed, 55 insertions(+), 15 deletions(-)
 create mode 100644 xen/arch/x86/include/asm/bootinfo.h
diff mbox series

Patch

diff --git a/xen/arch/x86/bzimage.c b/xen/arch/x86/bzimage.c
index ac4fd428be..dac2399b89 100644
--- a/xen/arch/x86/bzimage.c
+++ b/xen/arch/x86/bzimage.c
@@ -69,8 +69,6 @@  static __init int bzimage_check(struct setup_header *hdr, unsigned long len)
     return 1;
 }
 
-static unsigned long __initdata orig_image_len;
-
 unsigned long __init bzimage_headroom(void *image_start,
                                       unsigned long image_length)
 {
@@ -91,7 +89,6 @@  unsigned long __init bzimage_headroom(void *image_start,
     if ( elf_is_elfbinary(image_start, image_length) )
         return 0;
 
-    orig_image_len = image_length;
     headroom = output_length(image_start, image_length);
     if (gzip_check(image_start, image_length))
     {
@@ -105,11 +102,14 @@  unsigned long __init bzimage_headroom(void *image_start,
 }
 
 int __init bzimage_parse(void *image_base, void **image_start,
+                         unsigned int headroom,
                          unsigned long *image_len)
 {
     struct setup_header *hdr = (struct setup_header *)(*image_start);
     int err = bzimage_check(hdr, *image_len);
-    unsigned long output_len;
+    unsigned long output_len, orig_image_len;
+
+    orig_image_len = *image_len - headroom;
 
     if ( err < 0 )
         return err;
@@ -125,7 +125,7 @@  int __init bzimage_parse(void *image_base, void **image_start,
 
     BUG_ON(!(image_base < *image_start));
 
-    output_len = output_length(*image_start, orig_image_len);
+    output_len = output_length(*image_start, *image_len);
 
     if ( (err = perform_gunzip(image_base, *image_start, orig_image_len)) > 0 )
         err = decompress(*image_start, orig_image_len, image_base);
diff --git a/xen/arch/x86/hvm/dom0_build.c b/xen/arch/x86/hvm/dom0_build.c
index fd2cbf68bc..bf08998862 100644
--- a/xen/arch/x86/hvm/dom0_build.c
+++ b/xen/arch/x86/hvm/dom0_build.c
@@ -545,7 +545,8 @@  static int __init pvh_load_kernel(struct domain *d, const module_t *image,
     struct vcpu *v = d->vcpu[0];
     int rc;
 
-    if ( (rc = bzimage_parse(image_base, &image_start, &image_len)) != 0 )
+    if ( (rc = bzimage_parse(image_base, &image_start, image_headroom,
+                             &image_len)) != 0 )
     {
         printk("Error trying to detect bz compressed kernel\n");
         return rc;
diff --git a/xen/arch/x86/include/asm/bootinfo.h b/xen/arch/x86/include/asm/bootinfo.h
new file mode 100644
index 0000000000..a25054f372
--- /dev/null
+++ b/xen/arch/x86/include/asm/bootinfo.h
@@ -0,0 +1,18 @@ 
+#ifndef __ARCH_X86_BOOTINFO_H__
+#define __ARCH_X86_BOOTINFO_H__
+
+struct arch_bootmodule {
+    unsigned headroom;
+};
+
+#endif
+
+/*
+ * Local variables:
+ * mode: C
+ * c-file-style: "BSD"
+ * c-basic-offset: 4
+ * tab-width: 4
+ * indent-tabs-mode: nil
+ * End:
+ */
diff --git a/xen/arch/x86/include/asm/bzimage.h b/xen/arch/x86/include/asm/bzimage.h
index 7ed69d3910..dd784f32ef 100644
--- a/xen/arch/x86/include/asm/bzimage.h
+++ b/xen/arch/x86/include/asm/bzimage.h
@@ -5,7 +5,7 @@ 
 
 unsigned long bzimage_headroom(void *image_start, unsigned long image_length);
 
-int bzimage_parse(void *image_base, void **image_start,
+int bzimage_parse(void *image_base, void **image_start, unsigned int headroom,
                   unsigned long *image_len);
 
 #endif /* __X86_BZIMAGE_H__ */
diff --git a/xen/arch/x86/pv/dom0_build.c b/xen/arch/x86/pv/dom0_build.c
index c99135a552..6ed9f8bbed 100644
--- a/xen/arch/x86/pv/dom0_build.c
+++ b/xen/arch/x86/pv/dom0_build.c
@@ -416,7 +416,8 @@  int __init dom0_construct_pv(struct domain *d,
 
     d->max_pages = ~0U;
 
-    if ( (rc = bzimage_parse(image_base, &image_start, &image_len)) != 0 )
+    if ( (rc = bzimage_parse(image_base, &image_start, image_headroom,
+                             &image_len)) != 0 )
         return rc;
 
     if ( (rc = elf_init(&elf, image_start, image_len)) != 0 )
diff --git a/xen/arch/x86/setup.c b/xen/arch/x86/setup.c
index 708639b236..c0e8fc6ab7 100644
--- a/xen/arch/x86/setup.c
+++ b/xen/arch/x86/setup.c
@@ -273,10 +273,16 @@  static struct boot_info __initdata *boot_info;
 
 static void __init multiboot_to_bootinfo(multiboot_info_t *mbi)
 {
-    static struct boot_info __initdata info;
+    static struct boot_info       __initdata info;
+    static struct boot_module     __initdata boot_mods[1];
+    static struct arch_bootmodule __initdata arch_boot_mods[1];
+
+    info.mods = boot_mods;
 
     info.nr_mods = mbi->mods_count;
 
+    boot_mods[0].arch = &arch_boot_mods[0];
+
     boot_info = &info;
 }
 
@@ -961,7 +967,8 @@  static struct domain *__init create_dom0(const module_t *image,
         write_cr4(read_cr4() & ~X86_CR4_SMAP);
     }
 
-    if ( construct_dom0(d, image, headroom, initrd, cmdline) != 0 )
+    if ( construct_dom0(d, image, boot_info->mods[0].arch->headroom, initrd,
+                        cmdline) != 0 )
         panic("Could not construct domain 0\n");
 
     if ( cpu_has_smap )
@@ -985,7 +992,7 @@  void __init noreturn __start_xen(unsigned long mbi_p)
     unsigned int initrdidx, num_parked = 0;
     multiboot_info_t *mbi;
     module_t *mod;
-    unsigned long nr_pages, raw_max_page, modules_headroom, module_map[1];
+    unsigned long nr_pages, raw_max_page, module_map[1];
     int i, j, e820_warn = 0, bytes = 0;
     unsigned long eb_start, eb_end;
     bool acpi_boot_table_init_done = false, relocated = false;
@@ -1353,7 +1360,8 @@  void __init noreturn __start_xen(unsigned long mbi_p)
         mod[boot_info->nr_mods].mod_end = __2M_rwdata_end - _stext;
     }
 
-    modules_headroom = bzimage_headroom(bootstrap_map(mod), mod->mod_end);
+    boot_info->mods[0].arch->headroom = bzimage_headroom(bootstrap_map(mod),
+                                                         mod->mod_end);
     bootstrap_map(NULL);
 
 #ifndef highmem_start
@@ -1433,7 +1441,8 @@  void __init noreturn __start_xen(unsigned long mbi_p)
         /* Is the region suitable for relocating the multiboot modules? */
         for ( j = boot_info->nr_mods - 1; j >= 0; j-- )
         {
-            unsigned long headroom = j ? 0 : modules_headroom;
+            struct boot_module *boot_mods = boot_info->mods;
+            unsigned long headroom = j ? 0 : boot_mods[0].arch->headroom;
             unsigned long size = PAGE_ALIGN(headroom + mod[j].mod_end);
 
             if ( mod[j].reserved )
@@ -1481,7 +1490,7 @@  void __init noreturn __start_xen(unsigned long mbi_p)
 #endif
     }
 
-    if ( modules_headroom && !mod->reserved )
+    if ( boot_info->mods[0].arch->headroom && !mod->reserved )
         panic("Not enough memory to relocate the dom0 kernel image\n");
     for ( i = 0; i < boot_info->nr_mods; ++i )
     {
@@ -2021,7 +2030,7 @@  void __init noreturn __start_xen(unsigned long mbi_p)
      * We're going to setup domain0 using the module(s) that we stashed safely
      * above our heap. The second module, if present, is an initrd ramdisk.
      */
-    dom0 = create_dom0(mod, modules_headroom,
+    dom0 = create_dom0(mod, boot_info->mods[0].arch->headroom,
                        initrdidx < boot_info->nr_mods ? mod + initrdidx : NULL,
                        kextra, loader);
     if ( !dom0 )
diff --git a/xen/include/xen/bootinfo.h b/xen/include/xen/bootinfo.h
index 6a7d55d20e..b72ae31a66 100644
--- a/xen/include/xen/bootinfo.h
+++ b/xen/include/xen/bootinfo.h
@@ -3,8 +3,19 @@ 
 
 #include <xen/types.h>
 
+#ifdef CONFIG_X86
+#include <asm/bootinfo.h>
+#else
+    struct arch_bootmodule { };
+#endif
+
+struct boot_module {
+    struct arch_bootmodule *arch;
+};
+
 struct boot_info {
     unsigned int nr_mods;
+    struct boot_module *mods;
 };
 
 #endif