[RESEND][mmotm][PATCH v2, 2/5] Move dump_write() and dump_seek() into a header file

Daisuke HATAYAMA
2010-01-04T01:20:33Z

My next patch will replace ELF_CORE_EXTRA_* macros by functions,
putting them into other newly created *.c files. Then, each files will
contain dump_write(), where each pair of binfmt_*.c and elfcore.c
should be the same. So, this patch moves them into a header file with
dump_seek(). Also, the patch deletes confusing DUMP_WRITE macros in
each files.

Signed-off-by: Daisuke HATAYAMA <d.hatayama@jp.fujitsu.com>
---
fs/binfmt_aout.c | 49 +++++++----------------------------------
fs/binfmt_elf.c | 52 ++++++++++++--------------------------------
fs/binfmt_elf_fdpic.c | 54 ++++++++++++---------------------------------
include/linux/coredump.h | 41 ++++++++++++++++++++++++++++++++++
4 files changed, 79 insertions(+), 117 deletions(-)
create mode 100644 include/linux/coredump.h

diff --git a/fs/binfmt_aout.c b/fs/binfmt_aout.c
index 10717fb..75954e8 100644
--- a/fs/binfmt_aout.c
+++ b/fs/binfmt_aout.c
@@ -24,6 +24,7 @@
#include <linux/binfmts.h>
#include <linux/personality.h>
#include <linux/init.h>
+#include <linux/coredump.h>

#include <asm/system.h>
#include <asm/uaccess.h>
@@ -60,42 +61,6 @@ static int set_brk(unsigned long start, unsigned long end)
}

/*
- * These are the only things you should do on a core-file: use only these
- * macros to write out all the necessary info.
- */
-
-static int dump_write(struct file *file, const void *addr, int nr)
-{
- return file->f_op->write(file, addr, nr, &file->f_pos) == nr;
-}
-
-static int dump_seek(struct file *file, loff_t off)
-{
- if (file->f_op->llseek && file->f_op->llseek != no_llseek) {
- if (file->f_op->llseek(file, off, SEEK_CUR) < 0)
- return 0;
- } else {
- char *buf = (char *)get_zeroed_page(GFP_KERNEL);
- if (!buf)
- return 0;
- while (off > 0) {
- unsigned long n = off;
- if (n > PAGE_SIZE)
- n = PAGE_SIZE;
- if (!dump_write(file, buf, n))
- return 0;
- off -= n;
- }
- free_page((unsigned long)buf);
- }
- return 1;
-}
-
-#define DUMP_WRITE(addr, nr) \
- if (!dump_write(file, (void *)(addr), (nr))) \
- goto end_coredump;
-
-/*
* Routine writes a core dump image in the current directory.
* Currently only a stub-function.
*
@@ -146,7 +111,8 @@ static int aout_core_dump(struct coredump_params *cprm)

set_fs(KERNEL_DS);
/* struct user */
- DUMP_WRITE(&dump,sizeof(dump));
+ if (!dump_write(file, &dump, sizeof(dump)))
+ goto end_coredump;
/* Now dump all of the user data. Include malloced stuff as well */
if (!dump_seek(cprm->file, PAGE_SIZE - sizeof(dump)))
goto end_coredump;
@@ -156,17 +122,20 @@ static int aout_core_dump(struct coredump_params *cprm)
if (dump.u_dsize != 0) {
dump_start = START_DATA(dump);
dump_size = dump.u_dsize << PAGE_SHIFT;
- DUMP_WRITE(dump_start,dump_size);
+ if (!dump_write(file, dump_start, dump_size))
+ goto end_coredump;
}
/* Now prepare to dump the stack area */
if (dump.u_ssize != 0) {
dump_start = START_STACK(dump);
dump_size = dump.u_ssize << PAGE_SHIFT;
- DUMP_WRITE(dump_start,dump_size);
+ if (!dump_write(file, dump_start, dump_size))
+ goto end_coredump;
}
/* Finally dump the task struct. Not be used by gdb, but could be useful */
set_fs(KERNEL_DS);
- DUMP_WRITE(current,sizeof(*current));
+ if (!dump_write(file, current, sizeof(*current)))
+ goto end_coredump;
end_coredump:
set_fs(fs);
return has_dumped;
diff --git a/fs/binfmt_elf.c b/fs/binfmt_elf.c
index edd90c4..a0fe475 100644
--- a/fs/binfmt_elf.c
+++ b/fs/binfmt_elf.c
@@ -31,6 +31,7 @@
#include <linux/random.h>
#include <linux/elf.h>
#include <linux/utsname.h>
+#include <linux/coredump.h>
#include <asm/uaccess.h>
#include <asm/param.h>
#include <asm/page.h>
@@ -1108,36 +1109,6 @@ out:
* Modelled on fs/exec.c:aout_core_dump()
* Jeremy Fitzhardinge <jeremy@sw.oz.au>
*/
-/*
- * These are the only things you should do on a core-file: use only these
- * functions to write out all the necessary info.
- */
-static int dump_write(struct file *file, const void *addr, int nr)
-{
- return file->f_op->write(file, addr, nr, &file->f_pos) == nr;
-}
-
-static int dump_seek(struct file *file, loff_t off)
-{
- if (file->f_op->llseek && file->f_op->llseek != no_llseek) {
- if (file->f_op->llseek(file, off, SEEK_CUR) < 0)
- return 0;
- } else {
- char *buf = (char *)get_zeroed_page(GFP_KERNEL);
- if (!buf)
- return 0;
- while (off > 0) {
- unsigned long n = off;
- if (n > PAGE_SIZE)
- n = PAGE_SIZE;
- if (!dump_write(file, buf, n))
- return 0;
- off -= n;
- }
- free_page((unsigned long)buf);
- }
- return 1;
-}

/*
* Decide what to dump of a segment, part, all or none.
@@ -1272,11 +1243,6 @@ static int writenote(struct memelfnote *men, struct file *file,
}
#undef DUMP_WRITE

-#define DUMP_WRITE(addr, nr) \
- if ((size += (nr)) > cprm->limit || \
- !dump_write(cprm->file, (addr), (nr))) \
- goto end_coredump;
-
static void fill_elf_header(struct elfhdr *elf, int segs,
u16 machine, u32 flags, u8 osabi)
{
@@ -1957,7 +1923,10 @@ static int elf_core_dump(struct coredump_params *cprm)
fs = get_fs();
set_fs(KERNEL_DS);

- DUMP_WRITE(elf, sizeof(*elf));
+ size += sizeof(*elf);
+ if (size > cprm->limit || !dump_write(cprm->file, elf, sizeof(*elf)))
+ goto end_coredump;
+
offset += sizeof(*elf); /* Elf header */
offset += (segs + 1) * sizeof(struct elf_phdr); /* Program headers */
foffset = offset;
@@ -1971,7 +1940,11 @@ static int elf_core_dump(struct coredump_params *cprm)

fill_elf_note_phdr(&phdr, sz, offset);
offset += sz;
- DUMP_WRITE(&phdr, sizeof(phdr));
+
+ size += sizeof(phdr);
+ if (size > cprm->limit
+ || !dump_write(cprm->file, &phdr, sizeof(phdr)))
+ goto end_coredump;
}

dataoff = offset = roundup(offset, ELF_EXEC_PAGESIZE);
@@ -2002,7 +1975,10 @@ static int elf_core_dump(struct coredump_params *cprm)
phdr.p_flags |= PF_X;
phdr.p_align = ELF_EXEC_PAGESIZE;

- DUMP_WRITE(&phdr, sizeof(phdr));
+ size += sizeof(phdr);
+ if (size > cprm->limit
+ || !dump_write(cprm->file, &phdr, sizeof(phdr)))
+ goto end_coredump;
}

#ifdef ELF_CORE_WRITE_EXTRA_PHDRS
diff --git a/fs/binfmt_elf_fdpic.c b/fs/binfmt_elf_fdpic.c
index ab9aa76..d928e5f 100644
--- a/fs/binfmt_elf_fdpic.c
+++ b/fs/binfmt_elf_fdpic.c
@@ -34,6 +34,7 @@
#include <linux/elf.h>
#include <linux/elf-fdpic.h>
#include <linux/elfcore.h>
+#include <linux/coredump.h>

#include <asm/uaccess.h>
#include <asm/param.h>
@@ -1204,37 +1205,6 @@ static int elf_fdpic_map_file_by_direct_mmap(struct elf_fdpic_params *params,
#ifdef CONFIG_ELF_CORE

/*
- * These are the only things you should do on a core-file: use only these
- * functions to write out all the necessary info.
- */
-static int dump_write(struct file *file, const void *addr, int nr)
-{
- return file->f_op->write(file, addr, nr, &file->f_pos) == nr;
-}
-
-static int dump_seek(struct file *file, loff_t off)
-{
- if (file->f_op->llseek && file->f_op->llseek != no_llseek) {
- if (file->f_op->llseek(file, off, SEEK_CUR) < 0)
- return 0;
- } else {
- char *buf = (char *)get_zeroed_page(GFP_KERNEL);
- if (!buf)
- return 0;
- while (off > 0) {
- unsigned long n = off;
- if (n > PAGE_SIZE)
- n = PAGE_SIZE;
- if (!dump_write(file, buf, n))
- return 0;
- off -= n;
- }
- free_page((unsigned long)buf);
- }
- return 1;
-}
-
-/*
* Decide whether a segment is worth dumping; default is yes to be
* sure (missing info is worse than too much; etc).
* Personally I'd include everything, and use the coredump limit...
@@ -1342,11 +1312,6 @@ static int writenote(struct memelfnote *men, struct file *file,
}
#undef DUMP_WRITE

-#define DUMP_WRITE(addr, nr) \
- if ((size += (nr)) > cprm->limit || \
- !dump_write(cprm->file, (addr), (nr))) \
- goto end_coredump;
-
static inline void fill_elf_fdpic_header(struct elfhdr *elf, int segs)
{
memcpy(elf->e_ident, ELFMAG, SELFMAG);
@@ -1731,7 +1696,11 @@ static int elf_fdpic_core_dump(struct coredump_params *cprm)
fs = get_fs();
set_fs(KERNEL_DS);

- DUMP_WRITE(elf, sizeof(*elf));
+ size += sizeof(*elf);
+ if (size > cprm->limit
+ || !dump_write(cprm->file, elf, sizeof(*elf)))
+ goto end_coredump;
+
offset += sizeof(*elf); /* Elf header */
offset += (segs+1) * sizeof(struct elf_phdr); /* Program headers */
foffset = offset;
@@ -1748,7 +1717,11 @@ static int elf_fdpic_core_dump(struct coredump_params *cprm)

fill_elf_note_phdr(&phdr, sz, offset);
offset += sz;
- DUMP_WRITE(&phdr, sizeof(phdr));
+
+ size += sizeof(phdr);
+ if (size > cprm->limit
+ || !dump_write(cprm->file, &phdr, sizeof(phdr)))
+ goto end_coredump;
}

/* Page-align dumped data */
@@ -1782,7 +1755,10 @@ static int elf_fdpic_core_dump(struct coredump_params *cprm)
phdr.p_flags |= PF_X;
phdr.p_align = ELF_EXEC_PAGESIZE;

- DUMP_WRITE(&phdr, sizeof(phdr));
+ size += sizeof(phdr);
+ if (size > cprm->limit
+ || !dump_write(cprm->file, &phdr, sizeof(phdr)))
+ goto end_coredump;
}

#ifdef ELF_CORE_WRITE_EXTRA_PHDRS
diff --git a/include/linux/coredump.h b/include/linux/coredump.h
new file mode 100644
index 0000000..b3c91d7
--- /dev/null
+++ b/include/linux/coredump.h
@@ -0,0 +1,41 @@
+#ifndef _LINUX_COREDUMP_H
+#define _LINUX_COREDUMP_H
+
+#include <linux/types.h>
+#include <linux/mm.h>
+#include <linux/fs.h>
+
+/*
+ * These are the only things you should do on a core-file: use only these
+ * functions to write out all the necessary info.
+ */
+static inline int dump_write(struct file *file, const void *addr, int nr)
+{
+ return file->f_op->write(file, addr, nr, &file->f_pos) == nr;
+}
+
+static inline int dump_seek(struct file *file, loff_t off)
+{
+ if (file->f_op->llseek && file->f_op->llseek != no_llseek) {
+ if (file->f_op->llseek(file, off, SEEK_CUR) < 0)
+ return 0;
+ } else {
+ char *buf = (char *)get_zeroed_page(GFP_KERNEL);
+
+ if (!buf)
+ return 0;
+ while (off > 0) {
+ unsigned long n = off;
+
+ if (n > PAGE_SIZE)
+ n = PAGE_SIZE;
+ if (!dump_write(file, buf, n))
+ return 0;
+ off -= n;
+ }
+ free_page((unsigned long)buf);
+ }
+ return 1;
+}
+
+#endif /* _LINUX_COREDUMP_H */
--
1.6.5.1