Commit af7fa165 authored by Trond Myklebust's avatar Trond Myklebust
Browse files

NFS: Fix up the fsync code 



Christoph points out that the VFS will always flush out data before calling
nfs_fsync(), so we can dispense with a full call to nfs_wb_all(), and
replace that with a simpler call to nfs_commit_inode().

Signed-off-by: default avatarTrond Myklebust <Trond.Myklebust@netapp.com>
parent 77041ed9

fs/nfs/file.c

+21 −30
Original line number Diff line number Diff line
@@ -201,38 +201,12 @@ static loff_t nfs_file_llseek(struct file *filp, loff_t offset, int origin) 
	return loff;

}



/*

 * Helper for nfs_file_flush() and nfs_file_fsync()

 *

 * Notice that it clears the NFS_CONTEXT_ERROR_WRITE before synching to

 * disk, but it retrieves and clears ctx->error after synching, despite

 * the two being set at the same time in nfs_context_set_write_error().

 * This is because the former is used to notify the _next_ call to

 * nfs_file_write() that a write error occured, and hence cause it to

 * fall back to doing a synchronous write.

 */

static int nfs_do_fsync(struct nfs_open_context *ctx, struct inode *inode)

{

	int have_error, status;

	int ret = 0;



	have_error = test_and_clear_bit(NFS_CONTEXT_ERROR_WRITE, &ctx->flags);

	status = nfs_wb_all(inode);

	have_error |= test_bit(NFS_CONTEXT_ERROR_WRITE, &ctx->flags);

	if (have_error)

		ret = xchg(&ctx->error, 0);

	if (!ret)

		ret = status;

	return ret;

}



/*

 * Flush all dirty pages, and check for write errors.

 */

static int

nfs_file_flush(struct file *file, fl_owner_t id)

{

	struct nfs_open_context *ctx = nfs_file_open_context(file);

	struct dentry	*dentry = file->f_path.dentry;

	struct inode	*inode = dentry->d_inode;
@@ -245,7 +219,7 @@ nfs_file_flush(struct file *file, fl_owner_t id) 
		return 0;



	/* Flush writes to the server and return any errors */

	return nfs_do_fsync(ctx, inode);

	return vfs_fsync(file, 0);

}



static ssize_t
@@ -320,6 +294,13 @@ nfs_file_mmap(struct file * file, struct vm_area_struct * vma) 
 * Flush any dirty pages for this process, and check for write errors.

 * The return status from this call provides a reliable indication of

 * whether any write errors occurred for this process.

 *

 * Notice that it clears the NFS_CONTEXT_ERROR_WRITE before synching to

 * disk, but it retrieves and clears ctx->error after synching, despite

 * the two being set at the same time in nfs_context_set_write_error().

 * This is because the former is used to notify the _next_ call to

 * nfs_file_write() that a write error occured, and hence cause it to

 * fall back to doing a synchronous write.

 */

static int

nfs_file_fsync(struct file *file, int datasync)
@@ -327,13 +308,23 @@ nfs_file_fsync(struct file *file, int datasync) 
	struct dentry *dentry = file->f_path.dentry;

	struct nfs_open_context *ctx = nfs_file_open_context(file);

	struct inode *inode = dentry->d_inode;

	int have_error, status;

	int ret = 0;





	dprintk("NFS: fsync file(%s/%s) datasync %d\n",

			dentry->d_parent->d_name.name, dentry->d_name.name,

			datasync);



	nfs_inc_stats(inode, NFSIOS_VFSFSYNC);

	return nfs_do_fsync(ctx, inode);

	have_error = test_and_clear_bit(NFS_CONTEXT_ERROR_WRITE, &ctx->flags);

	status = nfs_commit_inode(inode, FLUSH_SYNC);

	have_error |= test_bit(NFS_CONTEXT_ERROR_WRITE, &ctx->flags);

	if (have_error)

		ret = xchg(&ctx->error, 0);

	if (!ret)

		ret = status;

	return ret;

}



/*
@@ -639,7 +630,7 @@ static ssize_t nfs_file_write(struct kiocb *iocb, const struct iovec *iov, 


	/* Return error values for O_DSYNC and IS_SYNC() */

	if (result >= 0 && nfs_need_sync_write(iocb->ki_filp, inode)) {

		int err = nfs_do_fsync(nfs_file_open_context(iocb->ki_filp), inode);

		int err = vfs_fsync(iocb->ki_filp, 0);

		if (err < 0)

			result = err;

	}
@@ -675,7 +666,7 @@ static ssize_t nfs_file_splice_write(struct pipe_inode_info *pipe, 
		written = ret;



	if (ret >= 0 && nfs_need_sync_write(filp, inode)) {

		int err = nfs_do_fsync(nfs_file_open_context(filp), inode);

		int err = vfs_fsync(filp, 0);

		if (err < 0)

			ret = err;

	}