elf_prstatus: collect the common part (everything before pr_reg) into a struct

Preparations to doing i386 compat elf_prstatus sanely - rather than duplicating
the beginning of compat_elf_prstatus, take these fields into a separate
structure (compat_elf_prstatus_common), so that it could be reused.  Due to
the incestous relationship between binfmt_elf.c and compat_binfmt_elf.c we
need the same shape change done to native struct elf_prstatus, gathering the
fields prior to pr_reg into a new structure (struct elf_prstatus_common).

Fortunately, offset of pr_reg is always a multiple of 16 with no padding
right before it, so it's possible to turn all the stuff prior to it into
a single member without disturbing the layout.

[build fix from Geert Uytterhoeven folded in]

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>

3 files changed, 10 insertions, 21 deletions

diff --git a/fs/binfmt_elf.c b/fs/binfmt_elf.c
index 8380478d3d92..4c1550b13899 100644
--- a/fs/binfmt_elf.c
+++ b/fs/binfmt_elf.c
@@ -1495,7 +1495,7 @@ static void fill_note(struct memelfnote *note, const char *name, int type,
  * fill up all the fields in prstatus from the given task struct, except
  * registers which need to be filled up separately.
  */
-static void fill_prstatus(struct elf_prstatus *prstatus,
+static void fill_prstatus(struct elf_prstatus_common *prstatus,
 		struct task_struct *p, long signr)
 {
 	prstatus->pr_info.si_signo = prstatus->pr_cursig = signr;
@@ -1736,7 +1736,7 @@ static int fill_thread_core_info(struct elf_thread_core_info *t,
 	 * than being the whole note contents.  We fill the reset in here.
 	 * We assume that regset 0 is NT_PRSTATUS.
 	 */
-	fill_prstatus(&t->prstatus, t->task, signr);
+	fill_prstatus(&t->prstatus.common, t->task, signr);
 	regset_get(t->task, &view->regsets[0],
 		   sizeof(t->prstatus.pr_reg), &t->prstatus.pr_reg);
 
@@ -1958,7 +1958,7 @@ static int elf_dump_thread_status(long signr, struct elf_thread_status *t)
 	struct task_struct *p = t->thread;
 	t->num_notes = 0;
 
-	fill_prstatus(&t->prstatus, p, signr);
+	fill_prstatus(&t->prstatus.common, p, signr);
 	elf_core_copy_task_regs(p, &t->prstatus.pr_reg);	
 	
 	fill_note(&t->notes[0], "CORE", NT_PRSTATUS, sizeof(t->prstatus),
@@ -2037,7 +2037,7 @@ static int fill_note_info(struct elfhdr *elf, int phdrs,
 	}
 	/* now collect the dump for the current */
 	memset(info->prstatus, 0, sizeof(*info->prstatus));
-	fill_prstatus(info->prstatus, current, siginfo->si_signo);
+	fill_prstatus(&info->prstatus->common, current, siginfo->si_signo);
 	elf_core_copy_regs(&info->prstatus->pr_reg, regs);
 
 	/* Set up header */
diff --git a/fs/binfmt_elf_fdpic.c b/fs/binfmt_elf_fdpic.c
index be4062b8ba75..03d81a14bcbf 100644
--- a/fs/binfmt_elf_fdpic.c
+++ b/fs/binfmt_elf_fdpic.c
@@ -1191,18 +1191,7 @@ static int elf_fdpic_map_file_by_direct_mmap(struct elf_fdpic_params *params,
 
 struct elf_prstatus_fdpic
 {
-	struct elf_siginfo 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 */
-	pid_t	pr_pid;
-	pid_t	pr_ppid;
-	pid_t	pr_pgrp;
-	pid_t	pr_sid;
-	struct __kernel_old_timeval pr_utime;	/* User time */
-	struct __kernel_old_timeval pr_stime;	/* System time */
-	struct __kernel_old_timeval pr_cutime;	/* Cumulative user time */
-	struct __kernel_old_timeval pr_cstime;	/* Cumulative system time */
+	struct elf_prstatus_common	common;
 	elf_gregset_t pr_reg;	/* GP registers */
 	/* When using FDPIC, the loadmap addresses need to be communicated
 	 * to GDB in order for GDB to do the necessary relocations.  The
@@ -1301,7 +1290,7 @@ static inline void fill_note(struct memelfnote *note, const char *name, int type
  * fill up all the fields in prstatus from the given task struct, except
  * registers which need to be filled up separately.
  */
-static void fill_prstatus(struct elf_prstatus_fdpic *prstatus,
+static void fill_prstatus(struct elf_prstatus_common *prstatus,
 			  struct task_struct *p, long signr)
 {
 	prstatus->pr_info.si_signo = prstatus->pr_cursig = signr;
@@ -1332,9 +1321,6 @@ static void fill_prstatus(struct elf_prstatus_fdpic *prstatus,
 	}
 	prstatus->pr_cutime = ns_to_kernel_old_timeval(p->signal->cutime);
 	prstatus->pr_cstime = ns_to_kernel_old_timeval(p->signal->cstime);
-
-	prstatus->pr_exec_fdpic_loadmap = p->mm->context.exec_fdpic_loadmap;
-	prstatus->pr_interp_fdpic_loadmap = p->mm->context.interp_fdpic_loadmap;
 }
 
 static int fill_psinfo(struct elf_prpsinfo *psinfo, struct task_struct *p,
@@ -1405,7 +1391,9 @@ static struct elf_thread_status *elf_dump_thread_status(long signr, struct task_
 	if (!t)
 		return t;
 
-	fill_prstatus(&t->prstatus, p, signr);
+	fill_prstatus(&t->prstatus.common, p, signr);
+	t->prstatus.pr_exec_fdpic_loadmap = p->mm->context.exec_fdpic_loadmap;
+	t->prstatus.pr_interp_fdpic_loadmap = p->mm->context.interp_fdpic_loadmap;
 	regset_get(p, &view->regsets[0],
 		   sizeof(t->prstatus.pr_reg), &t->prstatus.pr_reg);
 
diff --git a/fs/compat_binfmt_elf.c b/fs/compat_binfmt_elf.c
index 962df845ed51..feb48a5c2d44 100644
--- a/fs/compat_binfmt_elf.c
+++ b/fs/compat_binfmt_elf.c
@@ -50,6 +50,7 @@
  * which requires asm/elf.h to define compat_elf_gregset_t et al.
  */
 #define elf_prstatus	compat_elf_prstatus
+#define elf_prstatus_common	compat_elf_prstatus_common
 #define elf_prpsinfo	compat_elf_prpsinfo
 
 #undef ns_to_kernel_old_timeval