X-Git-Url: http://pilppa.org/gitweb/gitweb.cgi?a=blobdiff_plain;f=fs%2Ffuse%2Fdir.c;h=fd03330cadeb135979c5229eb861c89155df8de9;hb=8c79873da0d2bedf4ad6b868c54e426bb0a2fe38;hp=c4807b3fc8a360776bda6f976baebd26b5c9ae92;hpb=b4de123a0bc4a3f0c90899864d51299628729952;p=linux-2.6-omap-h63xx.git diff --git a/fs/fuse/dir.c b/fs/fuse/dir.c index c4807b3fc8a..fd03330cade 100644 --- a/fs/fuse/dir.c +++ b/fs/fuse/dir.c @@ -97,7 +97,7 @@ void fuse_invalidate_attr(struct inode *inode) * timeout is unknown (unlink, rmdir, rename and in some cases * lookup) */ -static void fuse_invalidate_entry_cache(struct dentry *entry) +void fuse_invalidate_entry_cache(struct dentry *entry) { fuse_dentry_settime(entry, 0); } @@ -112,18 +112,16 @@ static void fuse_invalidate_entry(struct dentry *entry) fuse_invalidate_entry_cache(entry); } -static void fuse_lookup_init(struct fuse_req *req, struct inode *dir, - struct dentry *entry, +static void fuse_lookup_init(struct fuse_conn *fc, struct fuse_req *req, + u64 nodeid, struct qstr *name, struct fuse_entry_out *outarg) { - struct fuse_conn *fc = get_fuse_conn(dir); - memset(outarg, 0, sizeof(struct fuse_entry_out)); req->in.h.opcode = FUSE_LOOKUP; - req->in.h.nodeid = get_node_id(dir); + req->in.h.nodeid = nodeid; req->in.numargs = 1; - req->in.args[0].size = entry->d_name.len + 1; - req->in.args[0].value = entry->d_name.name; + req->in.args[0].size = name->len + 1; + req->in.args[0].value = name->name; req->out.numargs = 1; if (fc->minor < 9) req->out.args[0].size = FUSE_COMPAT_ENTRY_OUT_SIZE; @@ -132,7 +130,7 @@ static void fuse_lookup_init(struct fuse_req *req, struct inode *dir, req->out.args[0].value = outarg; } -static u64 fuse_get_attr_version(struct fuse_conn *fc) +u64 fuse_get_attr_version(struct fuse_conn *fc) { u64 curr_version; @@ -189,7 +187,8 @@ static int fuse_dentry_revalidate(struct dentry *entry, struct nameidata *nd) attr_version = fuse_get_attr_version(fc); parent = dget_parent(entry); - fuse_lookup_init(req, parent->d_inode, entry, &outarg); + fuse_lookup_init(fc, req, get_node_id(parent->d_inode), + &entry->d_name, &outarg); request_send(fc, req); dput(parent); err = req->out.h.error; @@ -225,7 +224,7 @@ static int invalid_nodeid(u64 nodeid) return !nodeid || nodeid == FUSE_ROOT_ID; } -static struct dentry_operations fuse_dentry_operations = { +struct dentry_operations fuse_dentry_operations = { .d_revalidate = fuse_dentry_revalidate, }; @@ -239,85 +238,127 @@ int fuse_valid_type(int m) * Add a directory inode to a dentry, ensuring that no other dentry * refers to this inode. Called with fc->inst_mutex. */ -static int fuse_d_add_directory(struct dentry *entry, struct inode *inode) +static struct dentry *fuse_d_add_directory(struct dentry *entry, + struct inode *inode) { struct dentry *alias = d_find_alias(inode); - if (alias) { + if (alias && !(alias->d_flags & DCACHE_DISCONNECTED)) { /* This tries to shrink the subtree below alias */ fuse_invalidate_entry(alias); dput(alias); if (!list_empty(&inode->i_dentry)) - return -EBUSY; + return ERR_PTR(-EBUSY); + } else { + dput(alias); } - d_add(entry, inode); - return 0; + return d_splice_alias(inode, entry); } -static struct dentry *fuse_lookup(struct inode *dir, struct dentry *entry, - struct nameidata *nd) +int fuse_lookup_name(struct super_block *sb, u64 nodeid, struct qstr *name, + struct fuse_entry_out *outarg, struct inode **inode) { - int err; - struct fuse_entry_out outarg; - struct inode *inode = NULL; - struct fuse_conn *fc = get_fuse_conn(dir); + struct fuse_conn *fc = get_fuse_conn_super(sb); struct fuse_req *req; struct fuse_req *forget_req; u64 attr_version; + int err; - if (entry->d_name.len > FUSE_NAME_MAX) - return ERR_PTR(-ENAMETOOLONG); + *inode = NULL; + err = -ENAMETOOLONG; + if (name->len > FUSE_NAME_MAX) + goto out; req = fuse_get_req(fc); + err = PTR_ERR(req); if (IS_ERR(req)) - return ERR_CAST(req); + goto out; forget_req = fuse_get_req(fc); + err = PTR_ERR(forget_req); if (IS_ERR(forget_req)) { fuse_put_request(fc, req); - return ERR_CAST(forget_req); + goto out; } attr_version = fuse_get_attr_version(fc); - fuse_lookup_init(req, dir, entry, &outarg); + fuse_lookup_init(fc, req, nodeid, name, outarg); request_send(fc, req); err = req->out.h.error; fuse_put_request(fc, req); /* Zero nodeid is same as -ENOENT, but with valid timeout */ - if (!err && outarg.nodeid && - (invalid_nodeid(outarg.nodeid) || - !fuse_valid_type(outarg.attr.mode))) - err = -EIO; - if (!err && outarg.nodeid) { - inode = fuse_iget(dir->i_sb, outarg.nodeid, outarg.generation, - &outarg.attr, entry_attr_timeout(&outarg), - attr_version); - if (!inode) { - fuse_send_forget(fc, forget_req, outarg.nodeid, 1); - return ERR_PTR(-ENOMEM); - } + if (err || !outarg->nodeid) + goto out_put_forget; + + err = -EIO; + if (!outarg->nodeid) + goto out_put_forget; + if (!fuse_valid_type(outarg->attr.mode)) + goto out_put_forget; + + *inode = fuse_iget(sb, outarg->nodeid, outarg->generation, + &outarg->attr, entry_attr_timeout(outarg), + attr_version); + err = -ENOMEM; + if (!*inode) { + fuse_send_forget(fc, forget_req, outarg->nodeid, 1); + goto out; } + err = 0; + + out_put_forget: fuse_put_request(fc, forget_req); - if (err && err != -ENOENT) - return ERR_PTR(err); + out: + return err; +} + +static struct dentry *fuse_lookup(struct inode *dir, struct dentry *entry, + struct nameidata *nd) +{ + int err; + struct fuse_entry_out outarg; + struct inode *inode; + struct dentry *newent; + struct fuse_conn *fc = get_fuse_conn(dir); + bool outarg_valid = true; + + err = fuse_lookup_name(dir->i_sb, get_node_id(dir), &entry->d_name, + &outarg, &inode); + if (err == -ENOENT) { + outarg_valid = false; + err = 0; + } + if (err) + goto out_err; + + err = -EIO; + if (inode && get_node_id(inode) == FUSE_ROOT_ID) + goto out_iput; if (inode && S_ISDIR(inode->i_mode)) { mutex_lock(&fc->inst_mutex); - err = fuse_d_add_directory(entry, inode); + newent = fuse_d_add_directory(entry, inode); mutex_unlock(&fc->inst_mutex); - if (err) { - iput(inode); - return ERR_PTR(err); - } - } else - d_add(entry, inode); + err = PTR_ERR(newent); + if (IS_ERR(newent)) + goto out_iput; + } else { + newent = d_splice_alias(inode, entry); + } + entry = newent ? newent : entry; entry->d_op = &fuse_dentry_operations; - if (!err) + if (outarg_valid) fuse_change_entry_timeout(entry, &outarg); else fuse_invalidate_entry_cache(entry); - return NULL; + + return newent; + + out_iput: + iput(inode); + out_err: + return ERR_PTR(err); } /* @@ -857,7 +898,7 @@ static int fuse_access(struct inode *inode, int mask) return PTR_ERR(req); memset(&inarg, 0, sizeof(inarg)); - inarg.mask = mask; + inarg.mask = mask & (MAY_READ | MAY_WRITE | MAY_EXEC); req->in.h.opcode = FUSE_ACCESS; req->in.h.nodeid = get_node_id(inode); req->in.numargs = 1; @@ -886,7 +927,7 @@ static int fuse_access(struct inode *inode, int mask) * access request is sent. Execute permission is still checked * locally based on file mode. */ -static int fuse_permission(struct inode *inode, int mask, struct nameidata *nd) +static int fuse_permission(struct inode *inode, int mask) { struct fuse_conn *fc = get_fuse_conn(inode); bool refreshed = false; @@ -921,7 +962,7 @@ static int fuse_permission(struct inode *inode, int mask, struct nameidata *nd) exist. So if permissions are revoked this won't be noticed immediately, only after the attribute timeout has expired */ - } else if (nd && (nd->flags & (LOOKUP_ACCESS | LOOKUP_CHDIR))) { + } else if (mask & MAY_ACCESS) { err = fuse_access(inode, mask); } else if ((mask & MAY_EXEC) && S_ISREG(inode->i_mode)) { if (!(inode->i_mode & S_IXUGO)) { @@ -1106,6 +1147,50 @@ static void iattr_to_fattr(struct iattr *iattr, struct fuse_setattr_in *arg) } } +/* + * Prevent concurrent writepages on inode + * + * This is done by adding a negative bias to the inode write counter + * and waiting for all pending writes to finish. + */ +void fuse_set_nowrite(struct inode *inode) +{ + struct fuse_conn *fc = get_fuse_conn(inode); + struct fuse_inode *fi = get_fuse_inode(inode); + + BUG_ON(!mutex_is_locked(&inode->i_mutex)); + + spin_lock(&fc->lock); + BUG_ON(fi->writectr < 0); + fi->writectr += FUSE_NOWRITE; + spin_unlock(&fc->lock); + wait_event(fi->page_waitq, fi->writectr == FUSE_NOWRITE); +} + +/* + * Allow writepages on inode + * + * Remove the bias from the writecounter and send any queued + * writepages. + */ +static void __fuse_release_nowrite(struct inode *inode) +{ + struct fuse_inode *fi = get_fuse_inode(inode); + + BUG_ON(fi->writectr != FUSE_NOWRITE); + fi->writectr = 0; + fuse_flush_writepages(inode); +} + +void fuse_release_nowrite(struct inode *inode) +{ + struct fuse_conn *fc = get_fuse_conn(inode); + + spin_lock(&fc->lock); + __fuse_release_nowrite(inode); + spin_unlock(&fc->lock); +} + /* * Set attributes, and at the same time refresh them. * @@ -1122,6 +1207,8 @@ static int fuse_do_setattr(struct dentry *entry, struct iattr *attr, struct fuse_req *req; struct fuse_setattr_in inarg; struct fuse_attr_out outarg; + bool is_truncate = false; + loff_t oldsize; int err; if (!fuse_allow_task(fc, current)) @@ -1145,12 +1232,16 @@ static int fuse_do_setattr(struct dentry *entry, struct iattr *attr, send_sig(SIGXFSZ, current, 0); return -EFBIG; } + is_truncate = true; } req = fuse_get_req(fc); if (IS_ERR(req)) return PTR_ERR(req); + if (is_truncate) + fuse_set_nowrite(inode); + memset(&inarg, 0, sizeof(inarg)); memset(&outarg, 0, sizeof(outarg)); iattr_to_fattr(attr, &inarg); @@ -1181,16 +1272,44 @@ static int fuse_do_setattr(struct dentry *entry, struct iattr *attr, if (err) { if (err == -EINTR) fuse_invalidate_attr(inode); - return err; + goto error; } if ((inode->i_mode ^ outarg.attr.mode) & S_IFMT) { make_bad_inode(inode); - return -EIO; + err = -EIO; + goto error; + } + + spin_lock(&fc->lock); + fuse_change_attributes_common(inode, &outarg.attr, + attr_timeout(&outarg)); + oldsize = inode->i_size; + i_size_write(inode, outarg.attr.size); + + if (is_truncate) { + /* NOTE: this may release/reacquire fc->lock */ + __fuse_release_nowrite(inode); + } + spin_unlock(&fc->lock); + + /* + * Only call invalidate_inode_pages2() after removing + * FUSE_NOWRITE, otherwise fuse_launder_page() would deadlock. + */ + if (S_ISREG(inode->i_mode) && oldsize != outarg.attr.size) { + if (outarg.attr.size < oldsize) + fuse_truncate(inode->i_mapping, outarg.attr.size); + invalidate_inode_pages2(inode->i_mapping); } - fuse_change_attributes(inode, &outarg.attr, attr_timeout(&outarg), 0); return 0; + +error: + if (is_truncate) + fuse_release_nowrite(inode); + + return err; } static int fuse_setattr(struct dentry *entry, struct iattr *attr)