Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1753419Ab3F2RrP (ORCPT ); Sat, 29 Jun 2013 13:47:15 -0400 Received: from relay.parallels.com ([195.214.232.42]:52018 "EHLO relay.parallels.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752923Ab3F2RrL (ORCPT ); Sat, 29 Jun 2013 13:47:11 -0400 Subject: [PATCH 15/16] fuse: Turn writeback cache on To: miklos@szeredi.hu From: Maxim Patlasov Cc: riel@redhat.com, dev@parallels.com, xemul@parallels.com, fuse-devel@lists.sourceforge.net, bfoster@redhat.com, linux-kernel@vger.kernel.org, jbottomley@parallels.com, linux-mm@kvack.org, viro@zeniv.linux.org.uk, linux-fsdevel@vger.kernel.org, akpm@linux-foundation.org, fengguang.wu@intel.com, devel@openvz.org, mgorman@suse.de Date: Sat, 29 Jun 2013 21:47:01 +0400 Message-ID: <20130629174654.20175.80011.stgit@maximpc.sw.ru> In-Reply-To: <20130629172211.20175.70154.stgit@maximpc.sw.ru> References: <20130629172211.20175.70154.stgit@maximpc.sw.ru> User-Agent: StGit/0.15 MIME-Version: 1.0 Content-Type: text/plain; charset="utf-8" Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 4743 Lines: 140 From: Pavel Emelyanov Introduce a bit kernel and userspace exchange between each-other on the init stage and turn writeback on if the userspace want this and mount option 'allow_wbcache' is present (controlled by fusermount). Also add each writable file into per-inode write list and call the generic_file_aio_write to make use of the Linux page cache engine. Signed-off-by: Maxim Patlasov --- fs/fuse/file.c | 5 +++++ fs/fuse/fuse_i.h | 4 ++++ fs/fuse/inode.c | 13 +++++++++++++ include/uapi/linux/fuse.h | 2 ++ 4 files changed, 24 insertions(+), 0 deletions(-) diff --git a/fs/fuse/file.c b/fs/fuse/file.c index ea45cf3..6d30db1 100644 --- a/fs/fuse/file.c +++ b/fs/fuse/file.c @@ -208,6 +208,8 @@ void fuse_finish_open(struct inode *inode, struct file *file) spin_unlock(&fc->lock); fuse_invalidate_attr(inode); } + if ((file->f_mode & FMODE_WRITE) && fc->writeback_cache) + fuse_link_write_file(file); } int fuse_open_common(struct inode *inode, struct file *file, bool isdir) @@ -1225,6 +1227,9 @@ static ssize_t fuse_file_aio_write(struct kiocb *iocb, const struct iovec *iov, struct iov_iter i; loff_t endbyte = 0; + if (get_fuse_conn(inode)->writeback_cache) + return generic_file_aio_write(iocb, iov, nr_segs, pos); + WARN_ON(iocb->ki_pos != pos); ocount = 0; diff --git a/fs/fuse/fuse_i.h b/fs/fuse/fuse_i.h index f969b22..3494457 100644 --- a/fs/fuse/fuse_i.h +++ b/fs/fuse/fuse_i.h @@ -44,6 +44,10 @@ doing the mount will be allowed to access the filesystem */ #define FUSE_ALLOW_OTHER (1 << 1) +/** If the FUSE_ALLOW_WBCACHE flag is given, the filesystem + module will enable support of writback cache */ +#define FUSE_ALLOW_WBCACHE (1 << 2) + /** Number of page pointers embedded in fuse_req */ #define FUSE_REQ_INLINE_PAGES 1 diff --git a/fs/fuse/inode.c b/fs/fuse/inode.c index 591b46c..4beb8e3 100644 --- a/fs/fuse/inode.c +++ b/fs/fuse/inode.c @@ -459,6 +459,7 @@ enum { OPT_ALLOW_OTHER, OPT_MAX_READ, OPT_BLKSIZE, + OPT_ALLOW_WBCACHE, OPT_ERR }; @@ -471,6 +472,7 @@ static const match_table_t tokens = { {OPT_ALLOW_OTHER, "allow_other"}, {OPT_MAX_READ, "max_read=%u"}, {OPT_BLKSIZE, "blksize=%u"}, + {OPT_ALLOW_WBCACHE, "allow_wbcache"}, {OPT_ERR, NULL} }; @@ -544,6 +546,10 @@ static int parse_fuse_opt(char *opt, struct fuse_mount_data *d, int is_bdev) d->blksize = value; break; + case OPT_ALLOW_WBCACHE: + d->flags |= FUSE_ALLOW_WBCACHE; + break; + default: return 0; } @@ -571,6 +577,8 @@ static int fuse_show_options(struct seq_file *m, struct dentry *root) seq_printf(m, ",max_read=%u", fc->max_read); if (sb->s_bdev && sb->s_blocksize != FUSE_DEFAULT_BLKSIZE) seq_printf(m, ",blksize=%lu", sb->s_blocksize); + if (fc->flags & FUSE_ALLOW_WBCACHE) + seq_puts(m, ",allow_wbcache"); return 0; } @@ -888,6 +896,9 @@ static void process_init_reply(struct fuse_conn *fc, struct fuse_req *req) } if (arg->flags & FUSE_ASYNC_DIO) fc->async_dio = 1; + if (arg->flags & FUSE_WRITEBACK_CACHE && + fc->flags & FUSE_ALLOW_WBCACHE) + fc->writeback_cache = 1; } else { ra_pages = fc->max_read / PAGE_CACHE_SIZE; fc->no_lock = 1; @@ -916,6 +927,8 @@ static void fuse_send_init(struct fuse_conn *fc, struct fuse_req *req) FUSE_SPLICE_WRITE | FUSE_SPLICE_MOVE | FUSE_SPLICE_READ | FUSE_FLOCK_LOCKS | FUSE_IOCTL_DIR | FUSE_AUTO_INVAL_DATA | FUSE_DO_READDIRPLUS | FUSE_READDIRPLUS_AUTO | FUSE_ASYNC_DIO; + if (fc->flags & FUSE_ALLOW_WBCACHE) + arg->flags |= FUSE_WRITEBACK_CACHE; req->in.h.opcode = FUSE_INIT; req->in.numargs = 1; req->in.args[0].size = sizeof(*arg); diff --git a/include/uapi/linux/fuse.h b/include/uapi/linux/fuse.h index 60bb2f9..5c98dd1 100644 --- a/include/uapi/linux/fuse.h +++ b/include/uapi/linux/fuse.h @@ -219,6 +219,7 @@ struct fuse_file_lock { * FUSE_DO_READDIRPLUS: do READDIRPLUS (READDIR+LOOKUP in one) * FUSE_READDIRPLUS_AUTO: adaptive readdirplus * FUSE_ASYNC_DIO: asynchronous direct I/O submission + * FUSE_WRITEBACK_CACHE: use writeback cache for buffered writes */ #define FUSE_ASYNC_READ (1 << 0) #define FUSE_POSIX_LOCKS (1 << 1) @@ -236,6 +237,7 @@ struct fuse_file_lock { #define FUSE_DO_READDIRPLUS (1 << 13) #define FUSE_READDIRPLUS_AUTO (1 << 14) #define FUSE_ASYNC_DIO (1 << 15) +#define FUSE_WRITEBACK_CACHE (1 << 16) /** * CUSE INIT request/reply flags -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/