[XEN] Kexec / Kdump: Generic code

This patch implements the generic portion of the Kexec / Kdump port to Xen.

Signed-Off-By: Magnus Damm <magnus@valinux.co.jp>
Signed-Off-By: Simon Horman <horms@verge.net.au>

1 files changed, 137 insertions, 0 deletions

diff --git a/xen/include/xen/elfcore.h b/xen/include/xen/elfcore.h
new file mode 100644
index 0000000000..158621ef64
--- /dev/null
+++ b/xen/include/xen/elfcore.h
@@ -0,0 +1,137 @@
+/******************************************************************************
+ * elfcore.h
+ *
+ * Based heavily on include/linux/elfcore.h from Linux 2.6.16
+ * Naming scheeme based on include/xen/elf.h (not include/linux/elfcore.h)
+ *
+ */
+
+#ifndef __ELFCOREC_H__
+#define __ELFCOREC_H__
+
+#include <xen/types.h>
+#include <xen/elf.h>
+#include <asm/elf.h>
+#include <public/xen.h>
+
+#define NT_PRSTATUS     1
+
+typedef struct
+{
+    int signo;                       /* signal number */
+    int code;                        /* extra code */
+    int errno;                       /* errno */
+} ELF_Signifo;
+
+/* These seem to be the same length on all architectures on Linux */
+typedef int ELF_Pid;
+typedef struct {
+	long tv_sec;
+	long tv_usec;
+} ELF_Timeval;
+
+/*
+ * Definitions to generate Intel SVR4-like core files.
+ * These mostly have the same names as the SVR4 types with "elf_"
+ * tacked on the front to prevent clashes with linux definitions,
+ * and the typedef forms have been avoided.  This is mostly like
+ * the SVR4 structure, but more Linuxy, with things that Linux does
+ * not support and which gdb doesn't really use excluded.
+ */
+typedef struct
+{
+    ELF_Signifo pr_info;         /* Info associated with signal */
+    short pr_cursig;             /* Current signal */
+    unsigned long pr_sigpend;    /* Set of pending signals */
+    unsigned long pr_sighold;    /* Set of held signals */
+    ELF_Pid pr_pid;
+    ELF_Pid pr_ppid;
+    ELF_Pid pr_pgrp;
+    ELF_Pid pr_sid;
+    ELF_Timeval pr_utime;        /* User time */
+    ELF_Timeval pr_stime;        /* System time */
+    ELF_Timeval pr_cutime;       /* Cumulative user time */
+    ELF_Timeval pr_cstime;       /* Cumulative system time */
+    ELF_Gregset pr_reg;          /* GP registers - from asm header file */
+    int pr_fpvalid;              /* True if math co-processor being used.  */
+} ELF_Prstatus;
+
+/*
+ * The following data structures provide 64-bit ELF notes. In theory it should 
+ * be possible to support both 64-bit and 32-bit ELF files, but to keep it 
+ * simple we only do 64-bit.
+ *
+ * Please note that the current code aligns the 64-bit notes in the same
+ * way as Linux does. We are not following the 64-bit ELF spec, no one does.
+ *
+ * We are avoiding two problems by restricting us to 64-bit notes only:
+ * - Alignment of notes change with the word size. Ick.
+ * - We would need to tell kexec-tools which format we are using in the
+ *   hypervisor to make sure the right ELF format is generated.
+ *   That requires infrastructure. Let's not.
+ */
+
+#define ALIGN(x, n) ((x + ((1 << n) - 1)) / (1 << n))
+#define PAD32(x) u32 pad_data[ALIGN(x, 2)]
+
+#define TYPEDEF_NOTE(type, strlen, desctype)    \
+    typedef struct {                            \
+        union {                                 \
+            struct {                            \
+                Elf_Note note;                  \
+                unsigned char name[strlen];     \
+            } note;                             \
+            PAD32(sizeof(Elf_Note) + strlen);   \
+        } note;                                 \
+        union {                                 \
+            desctype desc;                      \
+            PAD32(sizeof(desctype));            \
+        } desc;                                 \
+    } __attribute__ ((packed)) type
+
+#define CORE_STR                "CORE"
+#define CORE_STR_LEN            5 /* including terminating zero */
+
+TYPEDEF_NOTE(crash_note_core_t, CORE_STR_LEN, ELF_Prstatus);
+
+#define XEN_STR                 "Xen"
+#define XEN_STR_LEN             4 /* including terminating zero */
+
+TYPEDEF_NOTE(crash_note_xen_core_t, XEN_STR_LEN, crash_xen_core_t);
+
+typedef struct {
+    unsigned long xen_major_version;
+    unsigned long xen_minor_version;
+    unsigned long xen_extra_version;
+    unsigned long xen_changeset;
+    unsigned long xen_compiler;
+    unsigned long xen_compile_date;
+    unsigned long xen_compile_time;
+    unsigned long tainted;
+} crash_xen_info_t;
+
+TYPEDEF_NOTE(crash_note_xen_info_t, XEN_STR_LEN, crash_xen_info_t);
+
+typedef struct {
+    crash_note_core_t core;
+    crash_note_xen_core_t xen_regs;
+    crash_note_xen_info_t xen_info;
+} __attribute__ ((packed)) crash_note_t;
+
+#define setup_crash_note(np, member, str, str_len, id) \
+  np->member.note.note.note.namesz = str_len; \
+  np->member.note.note.note.descsz = sizeof(np->member.desc.desc); \
+  np->member.note.note.note.type = id; \
+  memcpy(np->member.note.note.name, str, str_len)
+
+#endif /* __ELFCOREC_H__ */
+
+/*
+ * Local variables:
+ * mode: C
+ * c-set-style: "BSD"
+ * c-basic-offset: 4
+ * tab-width: 4
+ * indent-tabs-mode: nil
+ * End:
+ */