Re: [PATCH -next,v2] NFS: report and clear ENOSPC/EFBIG/EDQUOT writeback error on close() file
From: Trond Myklebust
Date: Tue Jun 14 2022 - 15:48:33 EST
On Tue, 2022-06-14 at 23:28 +0800, ChenXiaoSong wrote:
> Currently, we report and clear ENOSPC/EFBIG/EDQUOT writeback error on
> write(),
> write() file will report unexpected error if previous writeback error
> have not
> been cleared.
>
> Reproducer:
> nfs server | nfs client
> -----------------------------|--------------------------------------
> -------
> # No space left on server |
> fallocate -l 100G /svr/nospc |
> | mount -t nfs $nfs_server_ip:/ /mnt
> |
> | # Expected error: No space left on
> device
> | dd if=/dev/zero of=/mnt/file count=1
> ibs=10K
> |
> | # Release space on mountpoint
> | rm /mnt/nospc
> |
> | # Just write 512B and report
> unexpected error
> | dd if=/dev/zero of=/mnt/file count=1
> ibs=10K
>
> Fix this by clearing ENOSPC/EFBIG/EDQUOT writeback error on close
> file,
> it will not clear other errors that are not supposed to be reported
> by close().
>
> Signed-off-by: ChenXiaoSong <chenxiaosong2@xxxxxxxxxx>
> ---
> fs/nfs/file.c | 16 ++++++++--------
> fs/nfs/internal.h | 10 ++++++++++
> fs/nfs/nfs4file.c | 9 +++++++--
> 3 files changed, 25 insertions(+), 10 deletions(-)
>
> diff --git a/fs/nfs/file.c b/fs/nfs/file.c
> index 2d72b1b7ed74..275d1fdc7f9a 100644
> --- a/fs/nfs/file.c
> +++ b/fs/nfs/file.c
> @@ -138,7 +138,7 @@ static int
> nfs_file_flush(struct file *file, fl_owner_t id)
> {
> struct inode *inode = file_inode(file);
> - errseq_t since;
> + errseq_t since, error;
>
> dprintk("NFS: flush(%pD2)\n", file);
>
> @@ -149,7 +149,12 @@ nfs_file_flush(struct file *file, fl_owner_t id)
> /* Flush writes to the server and return any errors */
> since = filemap_sample_wb_err(file->f_mapping);
> nfs_wb_all(inode);
> - return filemap_check_wb_err(file->f_mapping, since);
> + error = filemap_check_wb_err(file->f_mapping, since);
> +
> + if (nfs_should_clear_wb_err(error))
> + file_check_and_advance_wb_err(file);
NACK. How many times do I have to repeat that we do NOT clear the error
log in flush()?
> +
> + return error;
> }
>
> ssize_t
> @@ -673,12 +678,7 @@ ssize_t nfs_file_write(struct kiocb *iocb,
> struct iov_iter *from)
> out:
> /* Return error values */
> error = filemap_check_wb_err(file->f_mapping, since);
> - switch (error) {
> - default:
> - break;
> - case -EDQUOT:
> - case -EFBIG:
> - case -ENOSPC:
> + if (nfs_should_clear_wb_err(error)) {
> nfs_wb_all(inode);
> error = file_check_and_advance_wb_err(file);
> if (error < 0)
> diff --git a/fs/nfs/internal.h b/fs/nfs/internal.h
> index 8f8cd6e2d4db..e49aad8f7d09 100644
> --- a/fs/nfs/internal.h
> +++ b/fs/nfs/internal.h
> @@ -859,3 +859,13 @@ static inline void nfs_set_port(struct sockaddr
> *sap, int *port,
>
> rpc_set_port(sap, *port);
> }
> +
> +static inline bool nfs_should_clear_wb_err(int error) {
> + switch (error) {
> + case -EDQUOT:
> + case -EFBIG:
> + case -ENOSPC:
> + return true;
> + }
> + return false;
> +}
> diff --git a/fs/nfs/nfs4file.c b/fs/nfs/nfs4file.c
> index 03d3a270eff4..ddf3f0abd55a 100644
> --- a/fs/nfs/nfs4file.c
> +++ b/fs/nfs/nfs4file.c
> @@ -113,7 +113,7 @@ static int
> nfs4_file_flush(struct file *file, fl_owner_t id)
> {
> struct inode *inode = file_inode(file);
> - errseq_t since;
> + errseq_t since, error;
>
> dprintk("NFS: flush(%pD2)\n", file);
>
> @@ -131,7 +131,12 @@ nfs4_file_flush(struct file *file, fl_owner_t
> id)
> /* Flush writes to the server and return any errors */
> since = filemap_sample_wb_err(file->f_mapping);
> nfs_wb_all(inode);
> - return filemap_check_wb_err(file->f_mapping, since);
> + error = filemap_check_wb_err(file->f_mapping, since);
> +
> + if (nfs_should_clear_wb_err(error))
> + file_check_and_advance_wb_err(file);
> +
> + return error;
> }
>
> #ifdef CONFIG_NFS_V4_2
--
Trond Myklebust
Linux NFS client maintainer, Hammerspace
trond.myklebust@xxxxxxxxxxxxxxx