fuse: Trust kernel i_mtime only
Let the kernel maintain i_mtime locally:
- clear S_NOCMTIME
- implement i_op->update_time()
- flush mtime on fsync and last close
- update i_mtime explicitly on truncate and fallocate
Fuse inode flag FUSE_I_MTIME_DIRTY serves as indication that local i_mtime
should be flushed to the server eventually.
Signed-off-by: Maxim Patlasov <MPatlasov@parallels.com>
Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
diff --git a/fs/fuse/dir.c b/fs/fuse/dir.c
index c52f143..5b4e035 100644
--- a/fs/fuse/dir.c
+++ b/fs/fuse/dir.c
@@ -842,8 +842,11 @@
struct fuse_conn *fc = get_fuse_conn(inode);
/* see the comment in fuse_change_attributes() */
- if (fc->writeback_cache && S_ISREG(inode->i_mode))
+ if (fc->writeback_cache && S_ISREG(inode->i_mode)) {
attr->size = i_size_read(inode);
+ attr->mtime = inode->i_mtime.tv_sec;
+ attr->mtimensec = inode->i_mtime.tv_nsec;
+ }
stat->dev = inode->i_sb->s_dev;
stat->ino = attr->ino;
@@ -1482,12 +1485,16 @@
FUSE_IOCTL_COMPAT | FUSE_IOCTL_DIR);
}
-static bool update_mtime(unsigned ivalid)
+static bool update_mtime(unsigned ivalid, bool trust_local_mtime)
{
/* Always update if mtime is explicitly set */
if (ivalid & ATTR_MTIME_SET)
return true;
+ /* Or if kernel i_mtime is the official one */
+ if (trust_local_mtime)
+ return true;
+
/* If it's an open(O_TRUNC) or an ftruncate(), don't update */
if ((ivalid & ATTR_SIZE) && (ivalid & (ATTR_OPEN | ATTR_FILE)))
return false;
@@ -1496,7 +1503,8 @@
return true;
}
-static void iattr_to_fattr(struct iattr *iattr, struct fuse_setattr_in *arg)
+static void iattr_to_fattr(struct iattr *iattr, struct fuse_setattr_in *arg,
+ bool trust_local_mtime)
{
unsigned ivalid = iattr->ia_valid;
@@ -1515,11 +1523,11 @@
if (!(ivalid & ATTR_ATIME_SET))
arg->valid |= FATTR_ATIME_NOW;
}
- if ((ivalid & ATTR_MTIME) && update_mtime(ivalid)) {
+ if ((ivalid & ATTR_MTIME) && update_mtime(ivalid, trust_local_mtime)) {
arg->valid |= FATTR_MTIME;
arg->mtime = iattr->ia_mtime.tv_sec;
arg->mtimensec = iattr->ia_mtime.tv_nsec;
- if (!(ivalid & ATTR_MTIME_SET))
+ if (!(ivalid & ATTR_MTIME_SET) && !trust_local_mtime)
arg->valid |= FATTR_MTIME_NOW;
}
}
@@ -1568,6 +1576,63 @@
spin_unlock(&fc->lock);
}
+static void fuse_setattr_fill(struct fuse_conn *fc, struct fuse_req *req,
+ struct inode *inode,
+ struct fuse_setattr_in *inarg_p,
+ struct fuse_attr_out *outarg_p)
+{
+ req->in.h.opcode = FUSE_SETATTR;
+ req->in.h.nodeid = get_node_id(inode);
+ req->in.numargs = 1;
+ req->in.args[0].size = sizeof(*inarg_p);
+ req->in.args[0].value = inarg_p;
+ req->out.numargs = 1;
+ if (fc->minor < 9)
+ req->out.args[0].size = FUSE_COMPAT_ATTR_OUT_SIZE;
+ else
+ req->out.args[0].size = sizeof(*outarg_p);
+ req->out.args[0].value = outarg_p;
+}
+
+/*
+ * Flush inode->i_mtime to the server
+ */
+int fuse_flush_mtime(struct file *file, bool nofail)
+{
+ struct inode *inode = file->f_mapping->host;
+ struct fuse_inode *fi = get_fuse_inode(inode);
+ struct fuse_conn *fc = get_fuse_conn(inode);
+ struct fuse_req *req = NULL;
+ struct fuse_setattr_in inarg;
+ struct fuse_attr_out outarg;
+ int err;
+
+ if (nofail) {
+ req = fuse_get_req_nofail_nopages(fc, file);
+ } else {
+ req = fuse_get_req_nopages(fc);
+ if (IS_ERR(req))
+ return PTR_ERR(req);
+ }
+
+ memset(&inarg, 0, sizeof(inarg));
+ memset(&outarg, 0, sizeof(outarg));
+
+ inarg.valid |= FATTR_MTIME;
+ inarg.mtime = inode->i_mtime.tv_sec;
+ inarg.mtimensec = inode->i_mtime.tv_nsec;
+
+ fuse_setattr_fill(fc, req, inode, &inarg, &outarg);
+ fuse_request_send(fc, req);
+ err = req->out.h.error;
+ fuse_put_request(fc, req);
+
+ if (!err)
+ clear_bit(FUSE_I_MTIME_DIRTY, &fi->state);
+
+ return err;
+}
+
/*
* Set attributes, and at the same time refresh them.
*
@@ -1588,6 +1653,7 @@
bool is_wb = fc->writeback_cache;
loff_t oldsize;
int err;
+ bool trust_local_mtime = is_wb && S_ISREG(inode->i_mode);
if (!(fc->flags & FUSE_DEFAULT_PERMISSIONS))
attr->ia_valid |= ATTR_FORCE;
@@ -1616,7 +1682,7 @@
memset(&inarg, 0, sizeof(inarg));
memset(&outarg, 0, sizeof(outarg));
- iattr_to_fattr(attr, &inarg);
+ iattr_to_fattr(attr, &inarg, trust_local_mtime);
if (file) {
struct fuse_file *ff = file->private_data;
inarg.valid |= FATTR_FH;
@@ -1627,17 +1693,7 @@
inarg.valid |= FATTR_LOCKOWNER;
inarg.lock_owner = fuse_lock_owner_id(fc, current->files);
}
- req->in.h.opcode = FUSE_SETATTR;
- req->in.h.nodeid = get_node_id(inode);
- req->in.numargs = 1;
- req->in.args[0].size = sizeof(inarg);
- req->in.args[0].value = &inarg;
- req->out.numargs = 1;
- if (fc->minor < 9)
- req->out.args[0].size = FUSE_COMPAT_ATTR_OUT_SIZE;
- else
- req->out.args[0].size = sizeof(outarg);
- req->out.args[0].value = &outarg;
+ fuse_setattr_fill(fc, req, inode, &inarg, &outarg);
fuse_request_send(fc, req);
err = req->out.h.error;
fuse_put_request(fc, req);
@@ -1654,6 +1710,12 @@
}
spin_lock(&fc->lock);
+ /* the kernel maintains i_mtime locally */
+ if (trust_local_mtime && (attr->ia_valid & ATTR_MTIME)) {
+ inode->i_mtime = attr->ia_mtime;
+ clear_bit(FUSE_I_MTIME_DIRTY, &fi->state);
+ }
+
fuse_change_attributes_common(inode, &outarg.attr,
attr_timeout(&outarg));
oldsize = inode->i_size;
@@ -1884,6 +1946,17 @@
return err;
}
+static int fuse_update_time(struct inode *inode, struct timespec *now,
+ int flags)
+{
+ if (flags & S_MTIME) {
+ inode->i_mtime = *now;
+ set_bit(FUSE_I_MTIME_DIRTY, &get_fuse_inode(inode)->state);
+ BUG_ON(!S_ISREG(inode->i_mode));
+ }
+ return 0;
+}
+
static const struct inode_operations fuse_dir_inode_operations = {
.lookup = fuse_lookup,
.mkdir = fuse_mkdir,
@@ -1923,6 +1996,7 @@
.getxattr = fuse_getxattr,
.listxattr = fuse_listxattr,
.removexattr = fuse_removexattr,
+ .update_time = fuse_update_time,
};
static const struct inode_operations fuse_symlink_inode_operations = {