[Cbe-oss-dev] [PATCH 8/9] Remove ctx_info and ctx_info_list

[Michael Ellerman]

Remove the ctx_info struct entirely, and also the ctx_info_list. This fixes
a race where two processes can clobber each other's ctx_info structs.

Instead of using the list, we just repeat the search through the file
descriptor table.

Signed-off-by: Michael Ellerman <michael at ellerman.id.au>
---
 arch/powerpc/platforms/cell/spufs/coredump.c |   45 ++++++--------------------
 1 files changed, 10 insertions(+), 35 deletions(-)

diff --git a/arch/powerpc/platforms/cell/spufs/coredump.c b/arch/powerpc/platforms/cell/spufs/coredump.c
index a1e8b0f..6663669 100644
--- a/arch/powerpc/platforms/cell/spufs/coredump.c
+++ b/arch/powerpc/platforms/cell/spufs/coredump.c
@@ -31,14 +31,6 @@
 
 #include "spufs.h"
 
-struct spufs_ctx_info {
-	struct list_head list;
-	int dfd;
-	struct spu_context *ctx;
-};
-
-static LIST_HEAD(ctx_info_list);
-
 static ssize_t do_coredump_read(int num, struct spu_context *ctx, void __user *buffer,
 				size_t size, loff_t *off)
 {
@@ -100,23 +92,6 @@ static int spufs_ctx_note_size(struct spu_context *ctx, int dfd)
 	return total;
 }
 
-static int spufs_add_one_context(struct spu_context *ctx, int dfd)
-{
-	struct spufs_ctx_info *ctx_info;
-	int size;
-
-	ctx_info = kzalloc(sizeof(*ctx_info), GFP_KERNEL);
-	if (unlikely(!ctx_info))
-		return -ENOMEM;
-
-	ctx_info->dfd = dfd;
-	ctx_info->ctx = ctx;
-
-	size = spufs_ctx_note_size(ctx, dfd);
-	list_add(&ctx_info->list, &ctx_info_list);
-	return size;
-}
-
 /*
  * The additional architecture-specific notes for Cell are various
  * context files in the spu context.
@@ -160,7 +135,7 @@ static int spufs_arch_notes_size(void)
 
 	fd = 0;
 	while ((ctx = coredump_next_context(&fd)) != NULL) {
-		rc = spufs_add_one_context(ctx, fd);
+		rc = spufs_ctx_note_size(ctx, fd);
 		if (rc < 0)
 			break;
 
@@ -220,17 +195,17 @@ out:
 
 static void spufs_arch_write_notes(struct file *file)
 {
-	int j;
-	struct spufs_ctx_info *ctx_info, *next;
+	struct spu_context *ctx;
+	int fd, j;
+
+	fd = 0;
+	while ((ctx = coredump_next_context(&fd)) != NULL) {
+		spu_acquire_saved(ctx);
 
-	list_for_each_entry_safe(ctx_info, next, &ctx_info_list, list) {
-		spu_acquire_saved(ctx_info->ctx);
 		for (j = 0; j < spufs_coredump_num_notes; j++)
-			spufs_arch_write_note(ctx_info->ctx, j, file,
-					      ctx_info->dfd);
-		spu_release_saved(ctx_info->ctx);
-		list_del(&ctx_info->list);
-		kfree(ctx_info);
+			spufs_arch_write_note(ctx, j, file, fd);
+
+		spu_release_saved(ctx);
 	}
 }
 
-- 
1.5.1.3.g7a33b