Re: sysfs: write returns ENOMEM?

[Pekka Enberg <penberg@gmail.com>]

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On 8/23/05, Nathan Scott <nathans@sgi.com> wrote:
> FWIW, all filesystems using the generic page cache routines are able
> to return this - see mm/filemap.c -> generic_file_buffered_write...

I don't think it makes much sense to fix this in individual
filesystems as many functions returning -NOMEM can be used in other
paths as well where they're ok.

Andrew, please consider picking this up for -mm. (I've included it as
an attachment as well as gmail will surely mess up the patch. Sorry.)

                               Pekka

[PATCH] VFS: return ENOBUFS instead of ENOMEM for vfs_write()

As noticed by Dmitry Torokhov, write() can not return ENOMEM:

http://www.opengroup.org/onlinepubs/000095399/functions/write.html

Currently almost all filesystems can return -ENOMEM due to
generic_file_buffered_write() in mm/filemap.c so filter out the invalid
error code in vfs_write().

Signed-off-by: Pekka Enberg <penberg@cs.helsinki.fi>
---

 read_write.c |    2 ++
 1 files changed, 2 insertions(+)

Index: 2.6-mm/fs/read_write.c
===================================================================
--- 2.6-mm.orig/fs/read_write.c
+++ 2.6-mm/fs/read_write.c
@@ -310,6 +310,8 @@ ssize_t vfs_write(struct file *file, con
                }
        }

+       if (ret == -ENOMEM)
+               ret = -ENOBUFS;
        return ret;
 }

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[PATCH] VFS: return ENOBUFS instead of ENOMEM for vfs_write()

As noticed by Dmitry Torokhov, write() can not return ENOMEM:

http://www.opengroup.org/onlinepubs/000095399/functions/write.html

Currently almost all filesystems can return -ENOMEM due to
generic_file_buffered_write() in mm/filemap.c so filter out the invalid
error code in vfs_write().

Signed-off-by: Pekka Enberg <penberg@cs.helsinki.fi>
---

 read_write.c |    2 ++
 1 files changed, 2 insertions(+)

Index: 2.6-mm/fs/read_write.c
===================================================================
--- 2.6-mm.orig/fs/read_write.c
+++ 2.6-mm/fs/read_write.c
@@ -310,6 +310,8 @@ ssize_t vfs_write(struct file *file, con
 		}
 	}
 
+	if (ret == -ENOMEM)
+		ret = -ENOBUFS;
 	return ret;
 }