Merge tag 'm68knommu-for-v5.19' of git://git.kernel.org/pub/scm/linux/kernel/git/gerg/m68knommu

Pull m68knommu updates from Greg Ungerer:
 "A collection of changes to add elf-fdpic loader support for m68k.

  Also a collection of various fixes. They include typo corrections,
  undefined symbol compilation fixes, removal of the ISA_DMA_API support
  and removal of unused code.

  Summary:

   - correctly set up ZERO_PAGE pointer

   - drop ISA_DMA_API support

   - fix comment typos

   - fixes for undefined symbols

   - remove unused code and variables

   - elf-fdpic loader support for m68k"

* tag 'm68knommu-for-v5.19' of git://git.kernel.org/pub/scm/linux/kernel/git/gerg/m68knommu:
  m68knommu: fix 68000 CPU link with no platform selected
  m68k: removed unused "mach_get_ss"
  m68knommu: fix undefined reference to `mach_get_rtc_pll'
  m68knommu: fix undefined reference to `_init_sp'
  m68knommu: allow elf_fdpic loader to be selected
  m68knommu: add definitions to support elf_fdpic program loader
  m68knommu: implement minimal regset support
  m68knommu: use asm-generic/mmu.h for nommu setups
  m68k: fix typos in comments
  m68k: coldfire: drop ISA_DMA_API support
  m68knommu: set ZERO_PAGE() to the allocated zeroed page

1 files changed, 58 insertions, 0 deletions

diff --git a/arch/m68k/kernel/ptrace.c b/arch/m68k/kernel/ptrace.c
index daebccdd2c09..0a4184a37461 100644
--- a/arch/m68k/kernel/ptrace.c
+++ b/arch/m68k/kernel/ptrace.c
@@ -19,6 +19,8 @@
 #include <linux/ptrace.h>
 #include <linux/user.h>
 #include <linux/signal.h>
+#include <linux/regset.h>
+#include <linux/elf.h>
 
 #include <linux/uaccess.h>
 #include <asm/page.h>
@@ -284,3 +286,59 @@ asmlinkage void syscall_trace_leave(void)
 	if (test_thread_flag(TIF_SYSCALL_TRACE))
 		ptrace_report_syscall_exit(task_pt_regs(current), 0);
 }
+
+#if defined(CONFIG_BINFMT_ELF_FDPIC) && defined(CONFIG_ELF_CORE)
+/*
+ * Currently the only thing that needs to use regsets for m68k is the
+ * coredump support of the elf_fdpic loader. Implement the minimum
+ * definitions required for that.
+ */
+static int m68k_regset_get(struct task_struct *target,
+			   const struct user_regset *regset,
+			   struct membuf to)
+{
+	struct pt_regs *ptregs = task_pt_regs(target);
+	u32 uregs[ELF_NGREG];
+
+	ELF_CORE_COPY_REGS(uregs, ptregs);
+	return membuf_write(&to, uregs, sizeof(uregs));
+}
+
+enum m68k_regset {
+	REGSET_GPR,
+#ifdef CONFIG_FPU
+	REGSET_FPU,
+#endif
+};
+
+static const struct user_regset m68k_user_regsets[] = {
+	[REGSET_GPR] = {
+		.core_note_type = NT_PRSTATUS,
+		.n = ELF_NGREG,
+		.size = sizeof(u32),
+		.align = sizeof(u16),
+		.regset_get = m68k_regset_get,
+	},
+#ifdef CONFIG_FPU
+	[REGSET_FPU] = {
+		.core_note_type = NT_PRFPREG,
+		.n = sizeof(struct user_m68kfp_struct) / sizeof(u32),
+		.size = sizeof(u32),
+		.align = sizeof(u32),
+	}
+#endif /* CONFIG_FPU */
+};
+
+static const struct user_regset_view user_m68k_view = {
+	.name = "m68k",
+	.e_machine = EM_68K,
+	.ei_osabi = ELF_OSABI,
+	.regsets = m68k_user_regsets,
+	.n = ARRAY_SIZE(m68k_user_regsets)
+};
+
+const struct user_regset_view *task_user_regset_view(struct task_struct *task)
+{
+	return &user_m68k_view;
+}
+#endif /* CONFIG_BINFMT_ELF_FDPIC && CONFIG_ELF_CORE */