Merge tag 'fuse-update-5.2' of git://git.kernel.org/pub/scm/linux/kernel/git/mszeredi/fuse

Pull fuse update from Miklos Szeredi:
 "Add more caching controls for userspace filesystems to use, as well as
  bug fixes and cleanups"

* tag 'fuse-update-5.2' of git://git.kernel.org/pub/scm/linux/kernel/git/mszeredi/fuse:
  fuse: clean up fuse_alloc_inode
  fuse: Add ioctl flag for x32 compat ioctl
  fuse: Convert fusectl to use the new mount API
  fuse: fix changelog entry for protocol 7.9
  fuse: fix changelog entry for protocol 7.12
  fuse: document fuse_fsync_in.fsync_flags
  fuse: Add FOPEN_STREAM to use stream_open()
  fuse: require /dev/fuse reads to have enough buffer capacity
  fuse: retrieve: cap requested size to negotiated max_write
  fuse: allow filesystems to have precise control over data cache
  fuse: convert printk -> pr_*
  fuse: honor RLIMIT_FSIZE in fuse_file_fallocate
  fuse: fix writepages on 32bit

6 files changed, 72 insertions, 29 deletions

diff --git a/fs/fuse/control.c b/fs/fuse/control.c
index fe80bea4ad89..14ce1e47f980 100644
--- a/fs/fuse/control.c
+++ b/fs/fuse/control.c
@@ -10,6 +10,7 @@
 
 #include <linux/init.h>
 #include <linux/module.h>
+#include <linux/fs_context.h>
 
 #define FUSE_CTL_SUPER_MAGIC 0x65735543
 
@@ -317,7 +318,7 @@ void fuse_ctl_remove_conn(struct fuse_conn *fc)
 	drop_nlink(d_inode(fuse_control_sb->s_root));
 }
 
-static int fuse_ctl_fill_super(struct super_block *sb, void *data, int silent)
+static int fuse_ctl_fill_super(struct super_block *sb, struct fs_context *fctx)
 {
 	static const struct tree_descr empty_descr = {""};
 	struct fuse_conn *fc;
@@ -343,10 +344,19 @@ static int fuse_ctl_fill_super(struct super_block *sb, void *data, int silent)
 	return 0;
 }
 
-static struct dentry *fuse_ctl_mount(struct file_system_type *fs_type,
-			int flags, const char *dev_name, void *raw_data)
+static int fuse_ctl_get_tree(struct fs_context *fc)
 {
-	return mount_single(fs_type, flags, raw_data, fuse_ctl_fill_super);
+	return vfs_get_super(fc, vfs_get_single_super, fuse_ctl_fill_super);
+}
+
+static const struct fs_context_operations fuse_ctl_context_ops = {
+	.get_tree	= fuse_ctl_get_tree,
+};
+
+static int fuse_ctl_init_fs_context(struct fs_context *fc)
+{
+	fc->ops = &fuse_ctl_context_ops;
+	return 0;
 }
 
 static void fuse_ctl_kill_sb(struct super_block *sb)
@@ -365,7 +375,7 @@ static void fuse_ctl_kill_sb(struct super_block *sb)
 static struct file_system_type fuse_ctl_fs_type = {
 	.owner		= THIS_MODULE,
 	.name		= "fusectl",
-	.mount		= fuse_ctl_mount,
+	.init_fs_context = fuse_ctl_init_fs_context,
 	.kill_sb	= fuse_ctl_kill_sb,
 };
 MODULE_ALIAS_FS("fusectl");
diff --git a/fs/fuse/cuse.c b/fs/fuse/cuse.c
index 55a26f351467..4b41df1d4642 100644
--- a/fs/fuse/cuse.c
+++ b/fs/fuse/cuse.c
@@ -33,6 +33,8 @@
  * closed.
  */
 
+#define pr_fmt(fmt) "CUSE: " fmt
+
 #include <linux/fuse.h>
 #include <linux/cdev.h>
 #include <linux/device.h>
@@ -225,7 +227,7 @@ static int cuse_parse_one(char **pp, char *end, char **keyp, char **valp)
 		return 0;
 
 	if (end[-1] != '\0') {
-		printk(KERN_ERR "CUSE: info not properly terminated\n");
+		pr_err("info not properly terminated\n");
 		return -EINVAL;
 	}
 
@@ -242,7 +244,7 @@ static int cuse_parse_one(char **pp, char *end, char **keyp, char **valp)
 		key = strstrip(key);
 
 	if (!strlen(key)) {
-		printk(KERN_ERR "CUSE: zero length info key specified\n");
+		pr_err("zero length info key specified\n");
 		return -EINVAL;
 	}
 
@@ -282,12 +284,11 @@ static int cuse_parse_devinfo(char *p, size_t len, struct cuse_devinfo *devinfo)
 		if (strcmp(key, "DEVNAME") == 0)
 			devinfo->name = val;
 		else
-			printk(KERN_WARNING "CUSE: unknown device info \"%s\"\n",
-			       key);
+			pr_warn("unknown device info \"%s\"\n", key);
 	}
 
 	if (!devinfo->name || !strlen(devinfo->name)) {
-		printk(KERN_ERR "CUSE: DEVNAME unspecified\n");
+		pr_err("DEVNAME unspecified\n");
 		return -EINVAL;
 	}
 
@@ -341,7 +342,7 @@ static void cuse_process_init_reply(struct fuse_conn *fc, struct fuse_req *req)
 	else
 		rc = register_chrdev_region(devt, 1, devinfo.name);
 	if (rc) {
-		printk(KERN_ERR "CUSE: failed to register chrdev region\n");
+		pr_err("failed to register chrdev region\n");
 		goto err;
 	}
 
diff --git a/fs/fuse/dev.c b/fs/fuse/dev.c
index 9971a35cf1ef..24ea19cfe07e 100644
--- a/fs/fuse/dev.c
+++ b/fs/fuse/dev.c
@@ -906,8 +906,8 @@ static int fuse_check_page(struct page *page)
 	       1 << PG_lru |
 	       1 << PG_active |
 	       1 << PG_reclaim))) {
-		printk(KERN_WARNING "fuse: trying to steal weird page\n");
-		printk(KERN_WARNING "  page=%p index=%li flags=%08lx, count=%i, mapcount=%i, mapping=%p\n", page, page->index, page->flags, page_count(page), page_mapcount(page), page->mapping);
+		pr_warn("trying to steal weird page\n");
+		pr_warn("  page=%p index=%li flags=%08lx, count=%i, mapcount=%i, mapping=%p\n", page, page->index, page->flags, page_count(page), page_mapcount(page), page->mapping);
 		return 1;
 	}
 	return 0;
@@ -1317,6 +1317,16 @@ static ssize_t fuse_dev_do_read(struct fuse_dev *fud, struct file *file,
 	unsigned reqsize;
 	unsigned int hash;
 
+	/*
+	 * Require sane minimum read buffer - that has capacity for fixed part
+	 * of any request header + negotated max_write room for data. If the
+	 * requirement is not satisfied return EINVAL to the filesystem server
+	 * to indicate that it is not following FUSE server/client contract.
+	 * Don't dequeue / abort any request.
+	 */
+	if (nbytes < max_t(size_t, FUSE_MIN_READ_BUFFER, 4096 + fc->max_write))
+		return -EINVAL;
+
  restart:
 	spin_lock(&fiq->waitq.lock);
 	err = -EAGAIN;
@@ -1749,7 +1759,7 @@ static int fuse_retrieve(struct fuse_conn *fc, struct inode *inode,
 	offset = outarg->offset & ~PAGE_MASK;
 	file_size = i_size_read(inode);
 
-	num = outarg->size;
+	num = min(outarg->size, fc->max_write);
 	if (outarg->offset > file_size)
 		num = 0;
 	else if (outarg->offset + num > file_size)
diff --git a/fs/fuse/file.c b/fs/fuse/file.c
index 06096b60f1df..3959f08279e6 100644
--- a/fs/fuse/file.c
+++ b/fs/fuse/file.c
@@ -178,7 +178,9 @@ void fuse_finish_open(struct inode *inode, struct file *file)
 
 	if (!(ff->open_flags & FOPEN_KEEP_CACHE))
 		invalidate_inode_pages2(inode->i_mapping);
-	if (ff->open_flags & FOPEN_NONSEEKABLE)
+	if (ff->open_flags & FOPEN_STREAM)
+		stream_open(inode, file);
+	else if (ff->open_flags & FOPEN_NONSEEKABLE)
 		nonseekable_open(inode, file);
 	if (fc->atomic_o_trunc && (file->f_flags & O_TRUNC)) {
 		struct fuse_inode *fi = get_fuse_inode(inode);
@@ -462,7 +464,7 @@ int fuse_fsync_common(struct file *file, loff_t start, loff_t end,
 
 	memset(&inarg, 0, sizeof(inarg));
 	inarg.fh = ff->fh;
-	inarg.fsync_flags = datasync ? 1 : 0;
+	inarg.fsync_flags = datasync ? FUSE_FSYNC_FDATASYNC : 0;
 	args.in.h.opcode = opcode;
 	args.in.h.nodeid = get_node_id(inode);
 	args.in.numargs = 1;
@@ -1586,7 +1588,7 @@ __acquires(fi->lock)
 {
 	struct fuse_conn *fc = get_fuse_conn(inode);
 	struct fuse_inode *fi = get_fuse_inode(inode);
-	size_t crop = i_size_read(inode);
+	loff_t crop = i_size_read(inode);
 	struct fuse_req *req;
 
 	while (fi->writectr >= 0 && !list_empty(&fi->queued_writes)) {
@@ -2576,8 +2578,13 @@ long fuse_do_ioctl(struct file *file, unsigned int cmd, unsigned long arg,
 #if BITS_PER_LONG == 32
 	inarg.flags |= FUSE_IOCTL_32BIT;
 #else
-	if (flags & FUSE_IOCTL_COMPAT)
+	if (flags & FUSE_IOCTL_COMPAT) {
 		inarg.flags |= FUSE_IOCTL_32BIT;
+#ifdef CONFIG_X86_X32
+		if (in_x32_syscall())
+			inarg.flags |= FUSE_IOCTL_COMPAT_X32;
+#endif
+	}
 #endif
 
 	/* assume all the iovs returned by client always fits in a page */
@@ -3044,6 +3051,13 @@ static long fuse_file_fallocate(struct file *file, int mode, loff_t offset,
 		}
 	}
 
+	if (!(mode & FALLOC_FL_KEEP_SIZE) &&
+	    offset + length > i_size_read(inode)) {
+		err = inode_newsize_ok(inode, offset + length);
+		if (err)
+			return err;
+	}
+
 	if (!(mode & FALLOC_FL_KEEP_SIZE))
 		set_bit(FUSE_I_SIZE_UNSTABLE, &fi->state);
 
diff --git a/fs/fuse/fuse_i.h b/fs/fuse/fuse_i.h
index 0920c0c032a0..24dbca777775 100644
--- a/fs/fuse/fuse_i.h
+++ b/fs/fuse/fuse_i.h
@@ -9,6 +9,10 @@
 #ifndef _FS_FUSE_I_H
 #define _FS_FUSE_I_H
 
+#ifndef pr_fmt
+# define pr_fmt(fmt) "fuse: " fmt
+#endif
+
 #include <linux/fuse.h>
 #include <linux/fs.h>
 #include <linux/mount.h>
@@ -690,6 +694,9 @@ struct fuse_conn {
 	/** Use enhanced/automatic page cache invalidation. */
 	unsigned auto_inval_data:1;
 
+	/** Filesystem is fully reponsible for page cache invalidation. */
+	unsigned explicit_inval_data:1;
+
 	/** Does the filesystem support readdirplus? */
 	unsigned do_readdirplus:1;
 
diff --git a/fs/fuse/inode.c b/fs/fuse/inode.c
index f485d09d14df..4bb885b0f032 100644
--- a/fs/fuse/inode.c
+++ b/fs/fuse/inode.c
@@ -81,14 +81,12 @@ struct fuse_forget_link *fuse_alloc_forget(void)
 
 static struct inode *fuse_alloc_inode(struct super_block *sb)
 {
-	struct inode *inode;
 	struct fuse_inode *fi;
 
-	inode = kmem_cache_alloc(fuse_inode_cachep, GFP_KERNEL);
-	if (!inode)
+	fi = kmem_cache_alloc(fuse_inode_cachep, GFP_KERNEL);
+	if (!fi)
 		return NULL;
 
-	fi = get_fuse_inode(inode);
 	fi->i_time = 0;
 	fi->inval_mask = 0;
 	fi->nodeid = 0;
@@ -100,11 +98,11 @@ static struct inode *fuse_alloc_inode(struct super_block *sb)
 	spin_lock_init(&fi->lock);
 	fi->forget = fuse_alloc_forget();
 	if (!fi->forget) {
-		kmem_cache_free(fuse_inode_cachep, inode);
+		kmem_cache_free(fuse_inode_cachep, fi);
 		return NULL;
 	}
 
-	return inode;
+	return &fi->inode;
 }
 
 static void fuse_free_inode(struct inode *inode)
@@ -233,7 +231,8 @@ void fuse_change_attributes(struct inode *inode, struct fuse_attr *attr,
 
 		if (oldsize != attr->size) {
 			truncate_pagecache(inode, attr->size);
-			inval = true;
+			if (!fc->explicit_inval_data)
+				inval = true;
 		} else if (fc->auto_inval_data) {
 			struct timespec64 new_mtime = {
 				.tv_sec = attr->mtime,
@@ -908,6 +907,8 @@ static void process_init_reply(struct fuse_conn *fc, struct fuse_req *req)
 				fc->dont_mask = 1;
 			if (arg->flags & FUSE_AUTO_INVAL_DATA)
 				fc->auto_inval_data = 1;
+			else if (arg->flags & FUSE_EXPLICIT_INVAL_DATA)
+				fc->explicit_inval_data = 1;
 			if (arg->flags & FUSE_DO_READDIRPLUS) {
 				fc->do_readdirplus = 1;
 				if (arg->flags & FUSE_READDIRPLUS_AUTO)
@@ -969,7 +970,7 @@ static void fuse_send_init(struct fuse_conn *fc, struct fuse_req *req)
 		FUSE_WRITEBACK_CACHE | FUSE_NO_OPEN_SUPPORT |
 		FUSE_PARALLEL_DIROPS | FUSE_HANDLE_KILLPRIV | FUSE_POSIX_ACL |
 		FUSE_ABORT_ERROR | FUSE_MAX_PAGES | FUSE_CACHE_SYMLINKS |
-		FUSE_NO_OPENDIR_SUPPORT;
+		FUSE_NO_OPENDIR_SUPPORT | FUSE_EXPLICIT_INVAL_DATA;
 	req->in.h.opcode = FUSE_INIT;
 	req->in.numargs = 1;
 	req->in.args[0].size = sizeof(*arg);
@@ -1393,8 +1394,8 @@ static int __init fuse_init(void)
 {
 	int res;
 
-	printk(KERN_INFO "fuse init (API version %i.%i)\n",
-	       FUSE_KERNEL_VERSION, FUSE_KERNEL_MINOR_VERSION);
+	pr_info("init (API version %i.%i)\n",
+		FUSE_KERNEL_VERSION, FUSE_KERNEL_MINOR_VERSION);
 
 	INIT_LIST_HEAD(&fuse_conn_list);
 	res = fuse_fs_init();
@@ -1430,7 +1431,7 @@ static int __init fuse_init(void)
 
 static void __exit fuse_exit(void)
 {
-	printk(KERN_DEBUG "fuse exit\n");
+	pr_debug("exit\n");
 
 	fuse_ctl_cleanup();
 	fuse_sysfs_cleanup();