Merge tag 'upstream-4.4-rc1' of git://git.infradead.org/linux-ubifs

Pull UBI/UBIFS updates from Richard Weinberger:

 - access time support for UBIFS by Dongsheng Yang

 - random cleanups and bug fixes all over the place

* tag 'upstream-4.4-rc1' of git://git.infradead.org/linux-ubifs:
  ubifs: introduce UBIFS_ATIME_SUPPORT to ubifs
  ubifs: make ubifs_[get|set]xattr atomic
  UBIFS: Delete unnecessary checks before the function call "iput"
  UBI: Remove in vain semicolon
  UBI: Fastmap: Fix PEB array type
  UBIFS: Fix possible memory leak in ubifs_readdir()
  fs/ubifs: remove unnecessary new_valid_dev check
  ubi: fastmap: Implement produce_free_peb()
  UBIFS: print verbose message when rescanning a corrupted node
  UBIFS: call dbg_is_power_cut() instead of reading c->dbg->pc_happened
  UBI: drop null test before destroy functions
  UBI: Update comments to reflect UBI_METAONLY flag
  UBI: Fix debug message
  UBI: Fix typo in comment
  UBI: Fastmap: Simplify expression
  UBIFS: fix a typo in comment of ubifs_budget_req
  UBIFS: use kmemdup rather than duplicating its implementation

11 files changed, 107 insertions, 34 deletions

diff --git a/fs/ubifs/Kconfig b/fs/ubifs/Kconfig
index ba66d508..7ff7712 100644
--- a/fs/ubifs/Kconfig
+++ b/fs/ubifs/Kconfig
@@ -35,3 +35,18 @@ config UBIFS_FS_ZLIB
 	default y
 	help
 	  Zlib compresses better than LZO but it is slower. Say 'Y' if unsure.
+
+config UBIFS_ATIME_SUPPORT
+	bool "Access time support" if UBIFS_FS
+	depends on UBIFS_FS
+	default n
+	help
+	  Originally UBIFS did not support atime, because it looked like a bad idea due
+	  increased flash wear. This option adds atime support and it is disabled by default
+	  to preserve the old behavior. If you enable this option, UBIFS starts updating atime,
+	  which means that file-system read operations will cause writes (inode atime
+	  updates). This may affect file-system performance and increase flash device wear,
+	  so be careful. How often atime is updated depends on the selected strategy:
+	  strictatime is the "heavy", relatime is "lighter", etc.
+
+	  If unsure, say 'N'
diff --git a/fs/ubifs/debug.c b/fs/ubifs/debug.c
index 4c46a98..595ca0d 100644
--- a/fs/ubifs/debug.c
+++ b/fs/ubifs/debug.c
@@ -2573,7 +2573,7 @@ int dbg_leb_write(struct ubifs_info *c, int lnum, const void *buf,
 {
 	int err, failing;
 
-	if (c->dbg->pc_happened)
+	if (dbg_is_power_cut(c))
 		return -EROFS;
 
 	failing = power_cut_emulated(c, lnum, 1);
@@ -2595,7 +2595,7 @@ int dbg_leb_change(struct ubifs_info *c, int lnum, const void *buf,
 {
 	int err;
 
-	if (c->dbg->pc_happened)
+	if (dbg_is_power_cut(c))
 		return -EROFS;
 	if (power_cut_emulated(c, lnum, 1))
 		return -EROFS;
@@ -2611,7 +2611,7 @@ int dbg_leb_unmap(struct ubifs_info *c, int lnum)
 {
 	int err;
 
-	if (c->dbg->pc_happened)
+	if (dbg_is_power_cut(c))
 		return -EROFS;
 	if (power_cut_emulated(c, lnum, 0))
 		return -EROFS;
@@ -2627,7 +2627,7 @@ int dbg_leb_map(struct ubifs_info *c, int lnum)
 {
 	int err;
 
-	if (c->dbg->pc_happened)
+	if (dbg_is_power_cut(c))
 		return -EROFS;
 	if (power_cut_emulated(c, lnum, 0))
 		return -EROFS;
diff --git a/fs/ubifs/dir.c b/fs/ubifs/dir.c
index 5c27c66..e49bd28 100644
--- a/fs/ubifs/dir.c
+++ b/fs/ubifs/dir.c
@@ -449,13 +449,14 @@ static int ubifs_readdir(struct file *file, struct dir_context *ctx)
 	}
 
 out:
+	kfree(file->private_data);
+	file->private_data = NULL;
+
 	if (err != -ENOENT) {
 		ubifs_err(c, "cannot find next direntry, error %d", err);
 		return err;
 	}
 
-	kfree(file->private_data);
-	file->private_data = NULL;
 	/* 2 is a special value indicating that there are no more direntries */
 	ctx->pos = 2;
 	return 0;
@@ -787,9 +788,6 @@ static int ubifs_mknod(struct inode *dir, struct dentry *dentry,
 
 	dbg_gen("dent '%pd' in dir ino %lu", dentry, dir->i_ino);
 
-	if (!new_valid_dev(rdev))
-		return -EINVAL;
-
 	if (S_ISBLK(mode) || S_ISCHR(mode)) {
 		dev = kmalloc(sizeof(union ubifs_dev_desc), GFP_NOFS);
 		if (!dev)
@@ -1188,6 +1186,9 @@ const struct inode_operations ubifs_dir_inode_operations = {
 	.getxattr    = ubifs_getxattr,
 	.listxattr   = ubifs_listxattr,
 	.removexattr = ubifs_removexattr,
+#ifdef CONFIG_UBIFS_ATIME_SUPPORT
+	.update_time = ubifs_update_time,
+#endif
 };
 
 const struct file_operations ubifs_dir_operations = {
diff --git a/fs/ubifs/file.c b/fs/ubifs/file.c
index a3dfe2a..0edc128 100644
--- a/fs/ubifs/file.c
+++ b/fs/ubifs/file.c
@@ -1354,6 +1354,47 @@ static inline int mctime_update_needed(const struct inode *inode,
 	return 0;
 }
 
+#ifdef CONFIG_UBIFS_ATIME_SUPPORT
+/**
+ * ubifs_update_time - update time of inode.
+ * @inode: inode to update
+ *
+ * This function updates time of the inode.
+ */
+int ubifs_update_time(struct inode *inode, struct timespec *time,
+			     int flags)
+{
+	struct ubifs_inode *ui = ubifs_inode(inode);
+	struct ubifs_info *c = inode->i_sb->s_fs_info;
+	struct ubifs_budget_req req = { .dirtied_ino = 1,
+			.dirtied_ino_d = ALIGN(ui->data_len, 8) };
+	int iflags = I_DIRTY_TIME;
+	int err, release;
+
+	err = ubifs_budget_space(c, &req);
+	if (err)
+		return err;
+
+	mutex_lock(&ui->ui_mutex);
+	if (flags & S_ATIME)
+		inode->i_atime = *time;
+	if (flags & S_CTIME)
+		inode->i_ctime = *time;
+	if (flags & S_MTIME)
+		inode->i_mtime = *time;
+
+	if (!(inode->i_sb->s_flags & MS_LAZYTIME))
+		iflags |= I_DIRTY_SYNC;
+
+	release = ui->dirty;
+	__mark_inode_dirty(inode, iflags);
+	mutex_unlock(&ui->ui_mutex);
+	if (release)
+		ubifs_release_budget(c, &req);
+	return 0;
+}
+#endif
+
 /**
  * update_ctime - update mtime and ctime of an inode.
  * @inode: inode to update
@@ -1537,6 +1578,9 @@ static int ubifs_file_mmap(struct file *file, struct vm_area_struct *vma)
 	if (err)
 		return err;
 	vma->vm_ops = &ubifs_file_vm_ops;
+#ifdef CONFIG_UBIFS_ATIME_SUPPORT
+	file_accessed(file);
+#endif
 	return 0;
 }
 
@@ -1557,6 +1601,9 @@ const struct inode_operations ubifs_file_inode_operations = {
 	.getxattr    = ubifs_getxattr,
 	.listxattr   = ubifs_listxattr,
 	.removexattr = ubifs_removexattr,
+#ifdef CONFIG_UBIFS_ATIME_SUPPORT
+	.update_time = ubifs_update_time,
+#endif
 };
 
 const struct inode_operations ubifs_symlink_inode_operations = {
@@ -1568,6 +1615,9 @@ const struct inode_operations ubifs_symlink_inode_operations = {
 	.getxattr    = ubifs_getxattr,
 	.listxattr   = ubifs_listxattr,
 	.removexattr = ubifs_removexattr,
+#ifdef CONFIG_UBIFS_ATIME_SUPPORT
+	.update_time = ubifs_update_time,
+#endif
 };
 
 const struct file_operations ubifs_file_operations = {
diff --git a/fs/ubifs/lpt.c b/fs/ubifs/lpt.c
index dc9f27e..9a51710 100644
--- a/fs/ubifs/lpt.c
+++ b/fs/ubifs/lpt.c
@@ -1498,11 +1498,10 @@ static struct ubifs_nnode *dirty_cow_nnode(struct ubifs_info *c,
 	}
 
 	/* nnode is being committed, so copy it */
-	n = kmalloc(sizeof(struct ubifs_nnode), GFP_NOFS);
+	n = kmemdup(nnode, sizeof(struct ubifs_nnode), GFP_NOFS);
 	if (unlikely(!n))
 		return ERR_PTR(-ENOMEM);
 
-	memcpy(n, nnode, sizeof(struct ubifs_nnode));
 	n->cnext = NULL;
 	__set_bit(DIRTY_CNODE, &n->flags);
 	__clear_bit(COW_CNODE, &n->flags);
@@ -1549,11 +1548,10 @@ static struct ubifs_pnode *dirty_cow_pnode(struct ubifs_info *c,
 	}
 
 	/* pnode is being committed, so copy it */
-	p = kmalloc(sizeof(struct ubifs_pnode), GFP_NOFS);
+	p = kmemdup(pnode, sizeof(struct ubifs_pnode), GFP_NOFS);
 	if (unlikely(!p))
 		return ERR_PTR(-ENOMEM);
 
-	memcpy(p, pnode, sizeof(struct ubifs_pnode));
 	p->cnext = NULL;
 	__set_bit(DIRTY_CNODE, &p->flags);
 	__clear_bit(COW_CNODE, &p->flags);
diff --git a/fs/ubifs/misc.h b/fs/ubifs/misc.h
index ee7cb5e..8ece6ca 100644
--- a/fs/ubifs/misc.h
+++ b/fs/ubifs/misc.h
@@ -155,13 +155,8 @@ static inline int ubifs_wbuf_sync(struct ubifs_wbuf *wbuf)
  */
 static inline int ubifs_encode_dev(union ubifs_dev_desc *dev, dev_t rdev)
 {
-	if (new_valid_dev(rdev)) {
-		dev->new = cpu_to_le32(new_encode_dev(rdev));
-		return sizeof(dev->new);
-	} else {
-		dev->huge = cpu_to_le64(huge_encode_dev(rdev));
-		return sizeof(dev->huge);
-	}
+	dev->new = cpu_to_le32(new_encode_dev(rdev));
+	return sizeof(dev->new);
 }
 
 /**
diff --git a/fs/ubifs/recovery.c b/fs/ubifs/recovery.c
index 695fc71..586d593 100644
--- a/fs/ubifs/recovery.c
+++ b/fs/ubifs/recovery.c
@@ -789,7 +789,7 @@ struct ubifs_scan_leb *ubifs_recover_leb(struct ubifs_info *c, int lnum,
 corrupted_rescan:
 	/* Re-scan the corrupted data with verbose messages */
 	ubifs_err(c, "corruption %d", ret);
-	ubifs_scan_a_node(c, buf, len, lnum, offs, 1);
+	ubifs_scan_a_node(c, buf, len, lnum, offs, 0);
 corrupted:
 	ubifs_scanned_corruption(c, lnum, offs, buf);
 	err = -EUCLEAN;
@@ -1331,8 +1331,7 @@ void ubifs_destroy_size_tree(struct ubifs_info *c)
 	struct size_entry *e, *n;
 
 	rbtree_postorder_for_each_entry_safe(e, n, &c->size_tree, rb) {
-		if (e->inode)
-			iput(e->inode);
+		iput(e->inode);
 		kfree(e);
 	}
 
@@ -1533,8 +1532,7 @@ int ubifs_recover_size(struct ubifs_info *c)
 				err = fix_size_in_place(c, e);
 				if (err)
 					return err;
-				if (e->inode)
-					iput(e->inode);
+				iput(e->inode);
 			}
 		}
 
diff --git a/fs/ubifs/super.c b/fs/ubifs/super.c
index 9547a278..8ee3133 100644
--- a/fs/ubifs/super.c
+++ b/fs/ubifs/super.c
@@ -128,7 +128,10 @@ struct inode *ubifs_iget(struct super_block *sb, unsigned long inum)
 	if (err)
 		goto out_ino;
 
-	inode->i_flags |= (S_NOCMTIME | S_NOATIME);
+	inode->i_flags |= S_NOCMTIME;
+#ifndef CONFIG_UBIFS_ATIME_SUPPORT
+	inode->i_flags |= S_NOATIME;
+#endif
 	set_nlink(inode, le32_to_cpu(ino->nlink));
 	i_uid_write(inode, le32_to_cpu(ino->uid));
 	i_gid_write(inode, le32_to_cpu(ino->gid));
@@ -2139,7 +2142,12 @@ static struct dentry *ubifs_mount(struct file_system_type *fs_type, int flags,
 		if (err)
 			goto out_deact;
 		/* We do not support atime */
-		sb->s_flags |= MS_ACTIVE | MS_NOATIME;
+		sb->s_flags |= MS_ACTIVE;
+#ifndef CONFIG_UBIFS_ATIME_SUPPORT
+		sb->s_flags |= MS_NOATIME;
+#else
+		ubifs_msg(c, "full atime support is enabled.");
+#endif
 	}
 
 	/* 'fill_super()' opens ubi again so we must close it here */
diff --git a/fs/ubifs/tnc.c b/fs/ubifs/tnc.c
index 957f575..fa9a20c 100644
--- a/fs/ubifs/tnc.c
+++ b/fs/ubifs/tnc.c
@@ -198,11 +198,10 @@ static struct ubifs_znode *copy_znode(struct ubifs_info *c,
 {
 	struct ubifs_znode *zn;
 
-	zn = kmalloc(c->max_znode_sz, GFP_NOFS);
+	zn = kmemdup(znode, c->max_znode_sz, GFP_NOFS);
 	if (unlikely(!zn))
 		return ERR_PTR(-ENOMEM);
 
-	memcpy(zn, znode, c->max_znode_sz);
 	zn->cnext = NULL;
 	__set_bit(DIRTY_ZNODE, &zn->flags);
 	__clear_bit(COW_ZNODE, &zn->flags);
diff --git a/fs/ubifs/ubifs.h b/fs/ubifs/ubifs.h
index de75902..01142e1 100644
--- a/fs/ubifs/ubifs.h
+++ b/fs/ubifs/ubifs.h
@@ -858,9 +858,9 @@ struct ubifs_compressor {
  * @mod_dent: non-zero if the operation removes or modifies an existing
  *            directory entry
  * @new_ino: non-zero if the operation adds a new inode
- * @new_ino_d: now much data newly created inode contains
+ * @new_ino_d: how much data newly created inode contains
  * @dirtied_ino: how many inodes the operation makes dirty
- * @dirtied_ino_d: now much data dirtied inode contains
+ * @dirtied_ino_d: how much data dirtied inode contains
  * @idx_growth: how much the index will supposedly grow
  * @data_growth: how much new data the operation will supposedly add
  * @dd_growth: how much data that makes other data dirty the operation will
@@ -1746,6 +1746,9 @@ int ubifs_calc_dark(const struct ubifs_info *c, int spc);
 /* file.c */
 int ubifs_fsync(struct file *file, loff_t start, loff_t end, int datasync);
 int ubifs_setattr(struct dentry *dentry, struct iattr *attr);
+#ifdef CONFIG_UBIFS_ATIME_SUPPORT
+int ubifs_update_time(struct inode *inode, struct timespec *time, int flags);
+#endif
 
 /* dir.c */
 struct inode *ubifs_new_inode(struct ubifs_info *c, const struct inode *dir,
diff --git a/fs/ubifs/xattr.c b/fs/ubifs/xattr.c
index fd65b3f..259fbab 100644
--- a/fs/ubifs/xattr.c
+++ b/fs/ubifs/xattr.c
@@ -200,6 +200,7 @@ static int change_xattr(struct ubifs_info *c, struct inode *host,
 	int err;
 	struct ubifs_inode *host_ui = ubifs_inode(host);
 	struct ubifs_inode *ui = ubifs_inode(inode);
+	void *buf = NULL;
 	struct ubifs_budget_req req = { .dirtied_ino = 2,
 		.dirtied_ino_d = ALIGN(size, 8) + ALIGN(host_ui->data_len, 8) };
 
@@ -208,14 +209,17 @@ static int change_xattr(struct ubifs_info *c, struct inode *host,
 	if (err)
 		return err;
 
-	kfree(ui->data);
-	ui->data = kmemdup(value, size, GFP_NOFS);
-	if (!ui->data) {
+	buf = kmemdup(value, size, GFP_NOFS);
+	if (!buf) {
 		err = -ENOMEM;
 		goto out_free;
 	}
+	mutex_lock(&ui->ui_mutex);
+	kfree(ui->data);
+	ui->data = buf;
 	inode->i_size = ui->ui_size = size;
 	ui->data_len = size;
+	mutex_unlock(&ui->ui_mutex);
 
 	mutex_lock(&host_ui->ui_mutex);
 	host->i_ctime = ubifs_current_time(host);
@@ -409,6 +413,7 @@ ssize_t ubifs_getxattr(struct dentry *dentry, const char *name, void *buf,
 	ubifs_assert(inode->i_size == ui->data_len);
 	ubifs_assert(ubifs_inode(host)->xattr_size > ui->data_len);
 
+	mutex_lock(&ui->ui_mutex);
 	if (buf) {
 		/* If @buf is %NULL we are supposed to return the length */
 		if (ui->data_len > size) {
@@ -423,6 +428,7 @@ ssize_t ubifs_getxattr(struct dentry *dentry, const char *name, void *buf,
 	err = ui->data_len;
 
 out_iput:
+	mutex_unlock(&ui->ui_mutex);
 	iput(inode);
 out_unlock:
 	kfree(xent);