linux-kernel - [PATCH v2 1/2] coredump: get rid of coredump

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Message-Id: <f4577fcdbdd1c7e1be373696ba97008ee9ae38ab.1460397009.git.osandov@fb.com>
Date:	Mon, 11 Apr 2016 11:15:55 -0700
From:	Omar Sandoval <osandov@...ndov.com>
To:	Al Viro <viro@...iv.linux.org.uk>
Cc:	linux-fsdevel@...r.kernel.org, linux-kernel@...r.kernel.org,
	kernel-team@...com, Omar Sandoval <osandov@...com>
Subject: [PATCH v2 1/2] coredump: get rid of coredump_params->written

From: Omar Sandoval <osandov@...com>

cprm->written is redundant with cprm->file->f_pos, so use that instead.
---
 arch/powerpc/platforms/cell/spufs/coredump.c | 5 +++--
 fs/binfmt_elf.c                              | 2 +-
 fs/binfmt_elf_fdpic.c                        | 2 +-
 fs/coredump.c                                | 8 +++-----
 include/linux/binfmts.h                      | 1 -
 5 files changed, 8 insertions(+), 10 deletions(-)

diff --git a/arch/powerpc/platforms/cell/spufs/coredump.c b/arch/powerpc/platforms/cell/spufs/coredump.c
index be6212ddbf06..84fb984f29c1 100644
--- a/arch/powerpc/platforms/cell/spufs/coredump.c
+++ b/arch/powerpc/platforms/cell/spufs/coredump.c
@@ -137,6 +137,7 @@ static int spufs_arch_write_note(struct spu_context *ctx, int i,
 	char *name;
 	char fullname[80], *buf;
 	struct elf_note en;
+	size_t skip;
 
 	buf = (void *)get_zeroed_page(GFP_KERNEL);
 	if (!buf)
@@ -171,8 +172,8 @@ static int spufs_arch_write_note(struct spu_context *ctx, int i,
 	if (rc < 0)
 		goto out;
 
-	if (!dump_skip(cprm,
-		       roundup(cprm->written - total + sz, 4) - cprm->written))
+	skip = roundup(cprm->file->f_pos - total + sz, 4) - cprm->file->f_pos;
+	if (!dump_skip(cprm, skip))
 		goto Eio;
 out:
 	free_page((unsigned long)buf);
diff --git a/fs/binfmt_elf.c b/fs/binfmt_elf.c
index 81381cc0dd17..56224ffa94d2 100644
--- a/fs/binfmt_elf.c
+++ b/fs/binfmt_elf.c
@@ -2273,7 +2273,7 @@ static int elf_core_dump(struct coredump_params *cprm)
 		goto end_coredump;
 
 	/* Align to page */
-	if (!dump_skip(cprm, dataoff - cprm->written))
+	if (!dump_skip(cprm, dataoff - cprm->file->f_pos))
 		goto end_coredump;
 
 	for (i = 0, vma = first_vma(current, gate_vma); vma != NULL;
diff --git a/fs/binfmt_elf_fdpic.c b/fs/binfmt_elf_fdpic.c
index 083ea2bc60ab..71ade0e556b7 100644
--- a/fs/binfmt_elf_fdpic.c
+++ b/fs/binfmt_elf_fdpic.c
@@ -1787,7 +1787,7 @@ static int elf_fdpic_core_dump(struct coredump_params *cprm)
 				goto end_coredump;
 	}
 
-	if (!dump_skip(cprm, dataoff - cprm->written))
+	if (!dump_skip(cprm, dataoff - cprm->file->f_pos))
 		goto end_coredump;
 
 	if (!elf_fdpic_dump_segments(cprm))
diff --git a/fs/coredump.c b/fs/coredump.c
index 47c32c3bfa1d..9db0c514438e 100644
--- a/fs/coredump.c
+++ b/fs/coredump.c
@@ -782,7 +782,7 @@ int dump_emit(struct coredump_params *cprm, const void *addr, int nr)
 	struct file *file = cprm->file;
 	loff_t pos = file->f_pos;
 	ssize_t n;
-	if (cprm->written + nr > cprm->limit)
+	if (pos + nr > cprm->limit)
 		return 0;
 	while (nr) {
 		if (dump_interrupted())
@@ -791,7 +791,6 @@ int dump_emit(struct coredump_params *cprm, const void *addr, int nr)
 		if (n <= 0)
 			return 0;
 		file->f_pos = pos;
-		cprm->written += n;
 		nr -= n;
 	}
 	return 1;
@@ -803,12 +802,11 @@ int dump_skip(struct coredump_params *cprm, size_t nr)
 	static char zeroes[PAGE_SIZE];
 	struct file *file = cprm->file;
 	if (file->f_op->llseek && file->f_op->llseek != no_llseek) {
-		if (cprm->written + nr > cprm->limit)
+		if (file->f_pos + nr > cprm->limit)
 			return 0;
 		if (dump_interrupted() ||
 		    file->f_op->llseek(file, nr, SEEK_CUR) < 0)
 			return 0;
-		cprm->written += nr;
 		return 1;
 	} else {
 		while (nr > PAGE_SIZE) {
@@ -823,7 +821,7 @@ EXPORT_SYMBOL(dump_skip);
 
 int dump_align(struct coredump_params *cprm, int align)
 {
-	unsigned mod = cprm->written & (align - 1);
+	unsigned mod = cprm->file->f_pos & (align - 1);
 	if (align & (align - 1))
 		return 0;
 	return mod ? dump_skip(cprm, align - mod) : 1;
diff --git a/include/linux/binfmts.h b/include/linux/binfmts.h
index 576e4639ca60..39c6d6e1234e 100644
--- a/include/linux/binfmts.h
+++ b/include/linux/binfmts.h
@@ -64,7 +64,6 @@ struct coredump_params {
 	struct file *file;
 	unsigned long limit;
 	unsigned long mm_flags;
-	loff_t written;
 };
 
 /*
-- 
2.8.0