From: Miklos Szeredi Date: Fri, 9 Sep 2005 20:10:37 +0000 (-0700) Subject: [PATCH] fuse: more flexible caching X-Git-Url: http://git.lede-project.org./?a=commitdiff_plain;h=45323fb76465a9576220c7427dbac7b1e7ad3caf;p=openwrt%2Fstaging%2Fblogic.git [PATCH] fuse: more flexible caching Make data caching behavior selectable on a per-open basis instead of per-mount. Compatibility for the old mount options 'kernel_cache' and 'direct_io' is retained in the userspace library (version 2.4.0-pre1 or later). Signed-off-by: Miklos Szeredi Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- diff --git a/Documentation/filesystems/fuse.txt b/Documentation/filesystems/fuse.txt index 83f96cf56960..6b5741e651a2 100644 --- a/Documentation/filesystems/fuse.txt +++ b/Documentation/filesystems/fuse.txt @@ -80,32 +80,6 @@ Mount options allowed to root, but this restriction can be removed with a (userspace) configuration option. -'kernel_cache' - - This option disables flushing the cache of the file contents on - every open(). This should only be enabled on filesystems, where the - file data is never changed externally (not through the mounted FUSE - filesystem). Thus it is not suitable for network filesystems and - other "intermediate" filesystems. - - NOTE: if this option is not specified (and neither 'direct_io') data - is still cached after the open(), so a read() system call will not - always initiate a read operation. - -'direct_io' - - This option disables the use of page cache (file content cache) in - the kernel for this filesystem. This has several affects: - - - Each read() or write() system call will initiate one or more - read or write operations, data will not be cached in the - kernel. - - - The return value of the read() and write() system calls will - correspond to the return values of the read and write - operations. This is useful for example if the file size is not - known in advance (before reading it). - 'max_read=N' With this option the maximum size of read operations can be set. diff --git a/fs/fuse/file.c b/fs/fuse/file.c index 224453557cf6..a8dc88527fbe 100644 --- a/fs/fuse/file.c +++ b/fs/fuse/file.c @@ -12,6 +12,8 @@ #include #include +static struct file_operations fuse_direct_io_file_operations; + int fuse_open_common(struct inode *inode, struct file *file, int isdir) { struct fuse_conn *fc = get_fuse_conn(inode); @@ -70,12 +72,14 @@ int fuse_open_common(struct inode *inode, struct file *file, int isdir) else request_send(fc, req); err = req->out.h.error; - if (!err && !(fc->flags & FUSE_KERNEL_CACHE)) - invalidate_inode_pages(inode->i_mapping); if (err) { fuse_request_free(ff->release_req); kfree(ff); } else { + if (!isdir && (outarg.open_flags & FOPEN_DIRECT_IO)) + file->f_op = &fuse_direct_io_file_operations; + if (!(outarg.open_flags & FOPEN_KEEP_CACHE)) + invalidate_inode_pages(inode->i_mapping); ff->fh = outarg.fh; file->private_data = ff; } @@ -544,12 +548,6 @@ static struct address_space_operations fuse_file_aops = { void fuse_init_file_inode(struct inode *inode) { - struct fuse_conn *fc = get_fuse_conn(inode); - - if (fc->flags & FUSE_DIRECT_IO) - inode->i_fop = &fuse_direct_io_file_operations; - else { - inode->i_fop = &fuse_file_operations; - inode->i_data.a_ops = &fuse_file_aops; - } + inode->i_fop = &fuse_file_operations; + inode->i_data.a_ops = &fuse_file_aops; } diff --git a/fs/fuse/fuse_i.h b/fs/fuse/fuse_i.h index 8593d5bae7a6..84849601363e 100644 --- a/fs/fuse/fuse_i.h +++ b/fs/fuse/fuse_i.h @@ -30,12 +30,6 @@ doing the mount will be allowed to access the filesystem */ #define FUSE_ALLOW_OTHER (1 << 1) -/** If the FUSE_KERNEL_CACHE flag is given, then cached data will not - be flushed on open */ -#define FUSE_KERNEL_CACHE (1 << 2) - -/** Bypass the page cache for read and write operations */ -#define FUSE_DIRECT_IO (1 << 3) /** FUSE inode */ struct fuse_inode { diff --git a/fs/fuse/inode.c b/fs/fuse/inode.c index 652c9d5df973..8dc66760b41a 100644 --- a/fs/fuse/inode.c +++ b/fs/fuse/inode.c @@ -257,8 +257,6 @@ enum { OPT_GROUP_ID, OPT_DEFAULT_PERMISSIONS, OPT_ALLOW_OTHER, - OPT_KERNEL_CACHE, - OPT_DIRECT_IO, OPT_MAX_READ, OPT_ERR }; @@ -270,8 +268,6 @@ static match_table_t tokens = { {OPT_GROUP_ID, "group_id=%u"}, {OPT_DEFAULT_PERMISSIONS, "default_permissions"}, {OPT_ALLOW_OTHER, "allow_other"}, - {OPT_KERNEL_CACHE, "kernel_cache"}, - {OPT_DIRECT_IO, "direct_io"}, {OPT_MAX_READ, "max_read=%u"}, {OPT_ERR, NULL} }; @@ -327,14 +323,6 @@ static int parse_fuse_opt(char *opt, struct fuse_mount_data *d) d->flags |= FUSE_ALLOW_OTHER; break; - case OPT_KERNEL_CACHE: - d->flags |= FUSE_KERNEL_CACHE; - break; - - case OPT_DIRECT_IO: - d->flags |= FUSE_DIRECT_IO; - break; - case OPT_MAX_READ: if (match_int(&args[0], &value)) return 0; @@ -363,10 +351,6 @@ static int fuse_show_options(struct seq_file *m, struct vfsmount *mnt) seq_puts(m, ",default_permissions"); if (fc->flags & FUSE_ALLOW_OTHER) seq_puts(m, ",allow_other"); - if (fc->flags & FUSE_KERNEL_CACHE) - seq_puts(m, ",kernel_cache"); - if (fc->flags & FUSE_DIRECT_IO) - seq_puts(m, ",direct_io"); if (fc->max_read != ~0) seq_printf(m, ",max_read=%u", fc->max_read); return 0; diff --git a/include/linux/fuse.h b/include/linux/fuse.h index cdfaa51b9018..c65124a213a1 100644 --- a/include/linux/fuse.h +++ b/include/linux/fuse.h @@ -14,7 +14,7 @@ #define FUSE_KERNEL_VERSION 7 /** Minor version number of this interface */ -#define FUSE_KERNEL_MINOR_VERSION 1 +#define FUSE_KERNEL_MINOR_VERSION 2 /** The node ID of the root inode */ #define FUSE_ROOT_ID 1 @@ -63,6 +63,15 @@ struct fuse_kstatfs { #define FATTR_MTIME (1 << 5) #define FATTR_CTIME (1 << 6) +/** + * Flags returned by the OPEN request + * + * FOPEN_DIRECT_IO: bypass page cache for this open file + * FOPEN_KEEP_CACHE: don't invalidate the data cache on open + */ +#define FOPEN_DIRECT_IO (1 << 0) +#define FOPEN_KEEP_CACHE (1 << 1) + enum fuse_opcode { FUSE_LOOKUP = 1, FUSE_FORGET = 2, /* no reply */