fuse: implement i_op->atomic_open()

[platform/adaptation/renesas_rcar/renesas_kernel.git] / fs / fuse / dir.c

diff --git a/fs/fuse/dir.c b/fs/fuse/dir.c
index df5ac04..e42442f 100644 (file)
--- a/fs/fuse/dir.c
+++ b/fs/fuse/dir.c
@@ -249,7 +249,7 @@ static struct dentry *fuse_d_add_directory(struct dentry *entry,
                /* This tries to shrink the subtree below alias */
                fuse_invalidate_entry(alias);
                dput(alias);
-               if (!list_empty(&inode->i_dentry))
+               if (!hlist_empty(&inode->i_dentry))
                        return ERR_PTR(-EBUSY);
        } else {
                dput(alias);
@@ -369,8 +369,9 @@ static struct dentry *fuse_lookup(struct inode *dir, struct dentry *entry,
  * If the filesystem doesn't support this, then fall back to separate
  * 'mknod' + 'open' requests.
  */
-static int fuse_create_open(struct inode *dir, struct dentry *entry,
-                           umode_t mode, struct nameidata *nd)
+static struct file *fuse_create_open(struct inode *dir, struct dentry *entry,
+                                    struct opendata *od, unsigned flags,
+                                    umode_t mode)
 {
        int err;
        struct inode *inode;
@@ -382,14 +383,11 @@ static int fuse_create_open(struct inode *dir, struct dentry *entry,
        struct fuse_entry_out outentry;
        struct fuse_file *ff;
        struct file *file;
-       int flags = nd->intent.open.flags;
-
-       if (fc->no_create)
-               return -ENOSYS;
 
        forget = fuse_alloc_forget();
+       err = -ENOMEM;
        if (!forget)
-               return -ENOMEM;
+               goto out_err;
 
        req = fuse_get_req(fc);
        err = PTR_ERR(req);
@@ -428,11 +426,8 @@ static int fuse_create_open(struct inode *dir, struct dentry *entry,
        req->out.args[1].value = &outopen;
        fuse_request_send(fc, req);
        err = req->out.h.error;
-       if (err) {
-               if (err == -ENOSYS)
-                       fc->no_create = 1;
+       if (err)
                goto out_free_ff;
-       }
 
        err = -EIO;
        if (!S_ISREG(outentry.attr.mode) || invalid_nodeid(outentry.nodeid))
@@ -448,28 +443,78 @@ static int fuse_create_open(struct inode *dir, struct dentry *entry,
                flags &= ~(O_CREAT | O_EXCL | O_TRUNC);
                fuse_sync_release(ff, flags);
                fuse_queue_forget(fc, forget, outentry.nodeid, 1);
-               return -ENOMEM;
+               err = -ENOMEM;
+               goto out_err;
        }
        kfree(forget);
        d_instantiate(entry, inode);
        fuse_change_entry_timeout(entry, &outentry);
        fuse_invalidate_attr(dir);
-       file = lookup_instantiate_filp(nd, entry, generic_file_open);
+       file = finish_open(od, entry, generic_file_open);
        if (IS_ERR(file)) {
                fuse_sync_release(ff, flags);
-               return PTR_ERR(file);
+       } else {
+               file->private_data = fuse_file_get(ff);
+               fuse_finish_open(inode, file);
        }
-       file->private_data = fuse_file_get(ff);
-       fuse_finish_open(inode, file);
-       return 0;
+       return file;
 
- out_free_ff:
+out_free_ff:
        fuse_file_free(ff);
- out_put_request:
+out_put_request:
        fuse_put_request(fc, req);
- out_put_forget_req:
+out_put_forget_req:
        kfree(forget);
-       return err;
+out_err:
+       return ERR_PTR(err);
+}
+
+static int fuse_mknod(struct inode *, struct dentry *, umode_t, dev_t);
+static struct file *fuse_atomic_open(struct inode *dir, struct dentry *entry,
+                                    struct opendata *od, unsigned flags,
+                                    umode_t mode, bool *created)
+{
+       int err;
+       struct fuse_conn *fc = get_fuse_conn(dir);
+       struct file *file;
+       struct dentry *res = NULL;
+
+       if (d_unhashed(entry)) {
+               res = fuse_lookup(dir, entry, NULL);
+               if (IS_ERR(res))
+                       return ERR_CAST(res);
+
+               if (res)
+                       entry = res;
+       }
+
+       if (!(flags & O_CREAT) || entry->d_inode)
+               goto no_open;
+
+       /* Only creates */
+       *created = true;
+
+       if (fc->no_create)
+               goto mknod;
+
+       file = fuse_create_open(dir, entry, od, flags, mode);
+       if (PTR_ERR(file) == -ENOSYS) {
+               fc->no_create = 1;
+               goto mknod;
+       }
+out_dput:
+       dput(res);
+       return file;
+
+mknod:
+       err = fuse_mknod(dir, entry, mode, 0);
+       if (err) {
+               file = ERR_PTR(err);
+               goto out_dput;
+       }
+no_open:
+       finish_no_open(od, res);
+       return NULL;
 }
 
 /*
@@ -573,12 +618,6 @@ static int fuse_mknod(struct inode *dir, struct dentry *entry, umode_t mode,
 static int fuse_create(struct inode *dir, struct dentry *entry, umode_t mode,
                       struct nameidata *nd)
 {
-       if (nd) {
-               int err = fuse_create_open(dir, entry, mode, nd);
-               if (err != -ENOSYS)
-                       return err;
-               /* Fall back on mknod */
-       }
        return fuse_mknod(dir, entry, mode, 0);
 }
 
@@ -775,6 +814,8 @@ static int fuse_link(struct dentry *entry, struct inode *newdir,
 static void fuse_fillattr(struct inode *inode, struct fuse_attr *attr,
                          struct kstat *stat)
 {
+       unsigned int blkbits;
+
        stat->dev = inode->i_sb->s_dev;
        stat->ino = attr->ino;
        stat->mode = (inode->i_mode & S_IFMT) | (attr->mode & 07777);
@@ -790,7 +831,13 @@ static void fuse_fillattr(struct inode *inode, struct fuse_attr *attr,
        stat->ctime.tv_nsec = attr->ctimensec;
        stat->size = attr->size;
        stat->blocks = attr->blocks;
-       stat->blksize = (1 << inode->i_blkbits);
+
+       if (attr->blksize != 0)
+               blkbits = ilog2(attr->blksize);
+       else
+               blkbits = inode->i_sb->s_blocksize_bits;
+
+       stat->blksize = 1 << blkbits;
 }
 
 static int fuse_do_getattr(struct inode *inode, struct kstat *stat,
@@ -863,6 +910,7 @@ int fuse_update_attributes(struct inode *inode, struct kstat *stat,
                if (stat) {
                        generic_fillattr(inode, stat);
                        stat->mode = fi->orig_i_mode;
+                       stat->ino = fi->orig_ino;
                }
        }
 
@@ -1637,6 +1685,7 @@ static const struct inode_operations fuse_dir_inode_operations = {
        .link           = fuse_link,
        .setattr        = fuse_setattr,
        .create         = fuse_create,
+       .atomic_open    = fuse_atomic_open,
        .mknod          = fuse_mknod,
        .permission     = fuse_permission,
        .getattr        = fuse_getattr,