From eb79f3af9395fbe448e91b0940a6c395b7d06be4 Mon Sep 17 00:00:00 2001 From: NeilBrown Date: Mon, 9 May 2022 18:20:48 -0700 Subject: [PATCH] nfs: rename nfs_direct_IO and use as ->swap_rw The nfs_direct_IO() exists to support SWAP IO, but hasn't worked for a while. We now need a ->swap_rw function which behaves slightly differently, returning zero for success rather than a byte count. So modify nfs_direct_IO accordingly, rename it, and use it as the ->swap_rw function. Link: https://lkml.kernel.org/r/165119301493.15698.7491285551903597618.stgit@noble.brown Signed-off-by: NeilBrown Reviewed-by: Christoph Hellwig Tested-by: Geert Uytterhoeven (on Renesas RSK+RZA1 with 32 MiB of SDRAM) Cc: David Howells Cc: Hugh Dickins Cc: Mel Gorman Cc: Miaohe Lin Cc: Trond Myklebust Signed-off-by: Andrew Morton --- fs/nfs/direct.c | 23 ++++++++++------------- fs/nfs/file.c | 5 +---- include/linux/nfs_fs.h | 2 +- 3 files changed, 12 insertions(+), 18 deletions(-) diff --git a/fs/nfs/direct.c b/fs/nfs/direct.c index 11c566d..4eb2a83 100644 --- a/fs/nfs/direct.c +++ b/fs/nfs/direct.c @@ -153,28 +153,25 @@ nfs_direct_count_bytes(struct nfs_direct_req *dreq, } /** - * nfs_direct_IO - NFS address space operation for direct I/O + * nfs_swap_rw - NFS address space operation for swap I/O * @iocb: target I/O control block * @iter: I/O buffer * - * The presence of this routine in the address space ops vector means - * the NFS client supports direct I/O. However, for most direct IO, we - * shunt off direct read and write requests before the VFS gets them, - * so this method is only ever called for swap. + * Perform IO to the swap-file. This is much like direct IO. */ -ssize_t nfs_direct_IO(struct kiocb *iocb, struct iov_iter *iter) +int nfs_swap_rw(struct kiocb *iocb, struct iov_iter *iter) { - struct inode *inode = iocb->ki_filp->f_mapping->host; - - /* we only support swap file calling nfs_direct_IO */ - if (!IS_SWAPFILE(inode)) - return 0; + ssize_t ret; VM_BUG_ON(iov_iter_count(iter) != PAGE_SIZE); if (iov_iter_rw(iter) == READ) - return nfs_file_direct_read(iocb, iter, true); - return nfs_file_direct_write(iocb, iter, true); + ret = nfs_file_direct_read(iocb, iter, true); + else + ret = nfs_file_direct_write(iocb, iter, true); + if (ret < 0) + return ret; + return 0; } static void nfs_direct_release_pages(struct page **pages, unsigned int npages) diff --git a/fs/nfs/file.c b/fs/nfs/file.c index 55bc8c8..0e7686a 100644 --- a/fs/nfs/file.c +++ b/fs/nfs/file.c @@ -488,10 +488,6 @@ static int nfs_swap_activate(struct swap_info_struct *sis, struct file *file, struct rpc_clnt *clnt = NFS_CLIENT(inode); struct nfs_client *cl = NFS_SERVER(inode)->nfs_client; - if (!file->f_mapping->a_ops->swap_rw) - /* Cannot support swap */ - return -EINVAL; - spin_lock(&inode->i_lock); blocks = inode->i_blocks; isize = inode->i_size; @@ -549,6 +545,7 @@ const struct address_space_operations nfs_file_aops = { .error_remove_page = generic_error_remove_page, .swap_activate = nfs_swap_activate, .swap_deactivate = nfs_swap_deactivate, + .swap_rw = nfs_swap_rw, }; /* diff --git a/include/linux/nfs_fs.h b/include/linux/nfs_fs.h index b48b925..fd55434 100644 --- a/include/linux/nfs_fs.h +++ b/include/linux/nfs_fs.h @@ -507,7 +507,7 @@ static inline const struct cred *nfs_file_cred(struct file *file) /* * linux/fs/nfs/direct.c */ -extern ssize_t nfs_direct_IO(struct kiocb *, struct iov_iter *); +int nfs_swap_rw(struct kiocb *iocb, struct iov_iter *iter); ssize_t nfs_file_direct_read(struct kiocb *iocb, struct iov_iter *iter, bool swap); ssize_t nfs_file_direct_write(struct kiocb *iocb, -- 2.7.4