From 8cbdf1e6f6876b37d2a0d96fd15ea9f90f7d51c1 Mon Sep 17 00:00:00 2001 From: Miklos Szeredi Date: Fri, 6 Jan 2006 00:19:38 -0800 Subject: [PATCH] fuse: support caching negative dentries Add support for caching negative dentries. Up till now, ->d_revalidate() always forced a new lookup on these. Now let the lookup method return a zero node ID (not used for anything else) meaning a negative entry, but with a positive cache timeout. The old way of signaling negative entry (replying ENOENT) still works. Userspace should check the ABI minor version to see whether sending a zero ID is allowed by the kernel or not. Signed-off-by: Miklos Szeredi Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- fs/fuse/dir.c | 64 +++++++++++++++++++++++++++++++++++++++-------------------- 1 file changed, 43 insertions(+), 21 deletions(-) (limited to 'fs/fuse/dir.c') diff --git a/fs/fuse/dir.c b/fs/fuse/dir.c index 0d1438a9dab3..4c127f2bc814 100644 --- a/fs/fuse/dir.c +++ b/fs/fuse/dir.c @@ -23,9 +23,26 @@ static inline unsigned long time_to_jiffies(unsigned long sec, static void fuse_change_timeout(struct dentry *entry, struct fuse_entry_out *o) { - struct fuse_inode *fi = get_fuse_inode(entry->d_inode); entry->d_time = time_to_jiffies(o->entry_valid, o->entry_valid_nsec); - fi->i_time = time_to_jiffies(o->attr_valid, o->attr_valid_nsec); + if (entry->d_inode) + get_fuse_inode(entry->d_inode)->i_time = + time_to_jiffies(o->attr_valid, o->attr_valid_nsec); +} + +void fuse_invalidate_attr(struct inode *inode) +{ + get_fuse_inode(inode)->i_time = jiffies - 1; +} + +static void fuse_invalidate_entry_cache(struct dentry *entry) +{ + entry->d_time = jiffies - 1; +} + +static void fuse_invalidate_entry(struct dentry *entry) +{ + d_invalidate(entry); + fuse_invalidate_entry_cache(entry); } static void fuse_lookup_init(struct fuse_req *req, struct inode *dir, @@ -45,15 +62,22 @@ static void fuse_lookup_init(struct fuse_req *req, struct inode *dir, static int fuse_dentry_revalidate(struct dentry *entry, struct nameidata *nd) { - if (!entry->d_inode || is_bad_inode(entry->d_inode)) + struct inode *inode = entry->d_inode; + + if (inode && is_bad_inode(inode)) return 0; else if (time_after(jiffies, entry->d_time)) { int err; struct fuse_entry_out outarg; - struct inode *inode = entry->d_inode; - struct fuse_inode *fi = get_fuse_inode(inode); - struct fuse_conn *fc = get_fuse_conn(inode); - struct fuse_req *req = fuse_get_request(fc); + struct fuse_conn *fc; + struct fuse_req *req; + + fuse_invalidate_entry_cache(entry); + if (!inode) + return 0; + + fc = get_fuse_conn(inode); + req = fuse_get_request(fc); if (!req) return 0; @@ -61,6 +85,7 @@ static int fuse_dentry_revalidate(struct dentry *entry, struct nameidata *nd) request_send(fc, req); err = req->out.h.error; if (!err) { + struct fuse_inode *fi = get_fuse_inode(inode); if (outarg.nodeid != get_node_id(inode)) { fuse_send_forget(fc, req, outarg.nodeid, 1); return 0; @@ -118,9 +143,9 @@ static struct dentry *fuse_lookup(struct inode *dir, struct dentry *entry, fuse_lookup_init(req, dir, entry, &outarg); request_send(fc, req); err = req->out.h.error; - if (!err && invalid_nodeid(outarg.nodeid)) + if (!err && outarg.nodeid && invalid_nodeid(outarg.nodeid)) err = -EIO; - if (!err) { + if (!err && outarg.nodeid) { inode = fuse_iget(dir->i_sb, outarg.nodeid, outarg.generation, &outarg.attr); if (!inode) { @@ -138,22 +163,13 @@ static struct dentry *fuse_lookup(struct inode *dir, struct dentry *entry, } d_add(entry, inode); entry->d_op = &fuse_dentry_operations; - if (inode) + if (!err) fuse_change_timeout(entry, &outarg); + else + fuse_invalidate_entry_cache(entry); return NULL; } -void fuse_invalidate_attr(struct inode *inode) -{ - get_fuse_inode(inode)->i_time = jiffies - 1; -} - -static void fuse_invalidate_entry(struct dentry *entry) -{ - d_invalidate(entry); - entry->d_time = jiffies - 1; -} - static int fuse_create_open(struct inode *dir, struct dentry *entry, int mode, struct nameidata *nd) { @@ -387,6 +403,7 @@ static int fuse_unlink(struct inode *dir, struct dentry *entry) inode->i_nlink = 0; fuse_invalidate_attr(inode); fuse_invalidate_attr(dir); + fuse_invalidate_entry_cache(entry); } else if (err == -EINTR) fuse_invalidate_entry(entry); return err; @@ -412,6 +429,7 @@ static int fuse_rmdir(struct inode *dir, struct dentry *entry) if (!err) { entry->d_inode->i_nlink = 0; fuse_invalidate_attr(dir); + fuse_invalidate_entry_cache(entry); } else if (err == -EINTR) fuse_invalidate_entry(entry); return err; @@ -447,6 +465,10 @@ static int fuse_rename(struct inode *olddir, struct dentry *oldent, fuse_invalidate_attr(olddir); if (olddir != newdir) fuse_invalidate_attr(newdir); + + /* newent will end up negative */ + if (newent->d_inode) + fuse_invalidate_entry_cache(newent); } else if (err == -EINTR) { /* If request was interrupted, DEITY only knows if the rename actually took place. If the invalidation -- cgit v1.2.3