Linux-libre 4.4-gnupck-4.4-gnu

9 files changed, 136 insertions, 29 deletions

diff --git a/fs/ext2/ext2.h b/fs/ext2/ext2.h
index 8d15febd0..4c69c94ca 100644
--- a/fs/ext2/ext2.h
+++ b/fs/ext2/ext2.h
@@ -684,6 +684,9 @@ struct ext2_inode_info {
 	struct rw_semaphore xattr_sem;
 #endif
 	rwlock_t i_meta_lock;
+#ifdef CONFIG_FS_DAX
+	struct rw_semaphore dax_sem;
+#endif
 
 	/*
 	 * truncate_mutex is for serialising ext2_truncate() against
@@ -699,6 +702,14 @@ struct ext2_inode_info {
 #endif
 };
 
+#ifdef CONFIG_FS_DAX
+#define dax_sem_down_write(ext2_inode)	down_write(&(ext2_inode)->dax_sem)
+#define dax_sem_up_write(ext2_inode)	up_write(&(ext2_inode)->dax_sem)
+#else
+#define dax_sem_down_write(ext2_inode)
+#define dax_sem_up_write(ext2_inode)
+#endif
+
 /*
  * Inode dynamic state flags
  */
diff --git a/fs/ext2/file.c b/fs/ext2/file.c
index 1982c3f11..11a42c5a0 100644
--- a/fs/ext2/file.c
+++ b/fs/ext2/file.c
@@ -27,27 +27,103 @@
 #include "acl.h"
 
 #ifdef CONFIG_FS_DAX
+/*
+ * The lock ordering for ext2 DAX fault paths is:
+ *
+ * mmap_sem (MM)
+ *   sb_start_pagefault (vfs, freeze)
+ *     ext2_inode_info->dax_sem
+ *       address_space->i_mmap_rwsem or page_lock (mutually exclusive in DAX)
+ *         ext2_inode_info->truncate_mutex
+ *
+ * The default page_lock and i_size verification done by non-DAX fault paths
+ * is sufficient because ext2 doesn't support hole punching.
+ */
 static int ext2_dax_fault(struct vm_area_struct *vma, struct vm_fault *vmf)
 {
-	return dax_fault(vma, vmf, ext2_get_block, NULL);
+	struct inode *inode = file_inode(vma->vm_file);
+	struct ext2_inode_info *ei = EXT2_I(inode);
+	int ret;
+
+	if (vmf->flags & FAULT_FLAG_WRITE) {
+		sb_start_pagefault(inode->i_sb);
+		file_update_time(vma->vm_file);
+	}
+	down_read(&ei->dax_sem);
+
+	ret = __dax_fault(vma, vmf, ext2_get_block, NULL);
+
+	up_read(&ei->dax_sem);
+	if (vmf->flags & FAULT_FLAG_WRITE)
+		sb_end_pagefault(inode->i_sb);
+	return ret;
 }
 
 static int ext2_dax_pmd_fault(struct vm_area_struct *vma, unsigned long addr,
 						pmd_t *pmd, unsigned int flags)
 {
-	return dax_pmd_fault(vma, addr, pmd, flags, ext2_get_block, NULL);
+	struct inode *inode = file_inode(vma->vm_file);
+	struct ext2_inode_info *ei = EXT2_I(inode);
+	int ret;
+
+	if (flags & FAULT_FLAG_WRITE) {
+		sb_start_pagefault(inode->i_sb);
+		file_update_time(vma->vm_file);
+	}
+	down_read(&ei->dax_sem);
+
+	ret = __dax_pmd_fault(vma, addr, pmd, flags, ext2_get_block, NULL);
+
+	up_read(&ei->dax_sem);
+	if (flags & FAULT_FLAG_WRITE)
+		sb_end_pagefault(inode->i_sb);
+	return ret;
 }
 
 static int ext2_dax_mkwrite(struct vm_area_struct *vma, struct vm_fault *vmf)
 {
-	return dax_mkwrite(vma, vmf, ext2_get_block, NULL);
+	struct inode *inode = file_inode(vma->vm_file);
+	struct ext2_inode_info *ei = EXT2_I(inode);
+	int ret;
+
+	sb_start_pagefault(inode->i_sb);
+	file_update_time(vma->vm_file);
+	down_read(&ei->dax_sem);
+
+	ret = __dax_mkwrite(vma, vmf, ext2_get_block, NULL);
+
+	up_read(&ei->dax_sem);
+	sb_end_pagefault(inode->i_sb);
+	return ret;
+}
+
+static int ext2_dax_pfn_mkwrite(struct vm_area_struct *vma,
+		struct vm_fault *vmf)
+{
+	struct inode *inode = file_inode(vma->vm_file);
+	struct ext2_inode_info *ei = EXT2_I(inode);
+	int ret = VM_FAULT_NOPAGE;
+	loff_t size;
+
+	sb_start_pagefault(inode->i_sb);
+	file_update_time(vma->vm_file);
+	down_read(&ei->dax_sem);
+
+	/* check that the faulting page hasn't raced with truncate */
+	size = (i_size_read(inode) + PAGE_SIZE - 1) >> PAGE_SHIFT;
+	if (vmf->pgoff >= size)
+		ret = VM_FAULT_SIGBUS;
+
+	up_read(&ei->dax_sem);
+	sb_end_pagefault(inode->i_sb);
+	return ret;
 }
 
 static const struct vm_operations_struct ext2_dax_vm_ops = {
 	.fault		= ext2_dax_fault,
 	.pmd_fault	= ext2_dax_pmd_fault,
 	.page_mkwrite	= ext2_dax_mkwrite,
-	.pfn_mkwrite	= dax_pfn_mkwrite,
+	.pfn_mkwrite	= ext2_dax_pfn_mkwrite,
 };
 
 static int ext2_file_mmap(struct file *file, struct vm_area_struct *vma)
diff --git a/fs/ext2/inode.c b/fs/ext2/inode.c
index c60a248c6..0aa9bf6e6 100644
--- a/fs/ext2/inode.c
+++ b/fs/ext2/inode.c
@@ -1085,6 +1085,7 @@ static void ext2_free_branches(struct inode *inode, __le32 *p, __le32 *q, int de
 		ext2_free_data(inode, p, q);
 }
 
+/* dax_sem must be held when calling this function */
 static void __ext2_truncate_blocks(struct inode *inode, loff_t offset)
 {
 	__le32 *i_data = EXT2_I(inode)->i_data;
@@ -1100,6 +1101,10 @@ static void __ext2_truncate_blocks(struct inode *inode, loff_t offset)
 	blocksize = inode->i_sb->s_blocksize;
 	iblock = (offset + blocksize-1) >> EXT2_BLOCK_SIZE_BITS(inode->i_sb);
 
+#ifdef CONFIG_FS_DAX
+	WARN_ON(!rwsem_is_locked(&ei->dax_sem));
+#endif
+
 	n = ext2_block_to_path(inode, iblock, offsets, NULL);
 	if (n == 0)
 		return;
@@ -1185,7 +1190,10 @@ static void ext2_truncate_blocks(struct inode *inode, loff_t offset)
 		return;
 	if (IS_APPEND(inode) || IS_IMMUTABLE(inode))
 		return;
+
+	dax_sem_down_write(EXT2_I(inode));
 	__ext2_truncate_blocks(inode, offset);
+	dax_sem_up_write(EXT2_I(inode));
 }
 
 static int ext2_setsize(struct inode *inode, loff_t newsize)
@@ -1213,8 +1221,10 @@ static int ext2_setsize(struct inode *inode, loff_t newsize)
 	if (error)
 		return error;
 
+	dax_sem_down_write(EXT2_I(inode));
 	truncate_setsize(inode, newsize);
 	__ext2_truncate_blocks(inode, newsize);
+	dax_sem_up_write(EXT2_I(inode));
 
 	inode->i_mtime = inode->i_ctime = CURRENT_TIME_SEC;
 	if (inode_needs_sync(inode)) {
diff --git a/fs/ext2/namei.c b/fs/ext2/namei.c
index b4841e306..3267a80db 100644
--- a/fs/ext2/namei.c
+++ b/fs/ext2/namei.c
@@ -143,9 +143,6 @@ static int ext2_mknod (struct inode * dir, struct dentry *dentry, umode_t mode,
 	struct inode * inode;
 	int err;
 
-	if (!new_valid_dev(rdev))
-		return -EINVAL;
-
 	err = dquot_initialize(dir);
 	if (err)
 		return err;
diff --git a/fs/ext2/super.c b/fs/ext2/super.c
index 900e19cf9..748d35afc 100644
--- a/fs/ext2/super.c
+++ b/fs/ext2/super.c
@@ -192,6 +192,9 @@ static void init_once(void *foo)
 	init_rwsem(&ei->xattr_sem);
 #endif
 	mutex_init(&ei->truncate_mutex);
+#ifdef CONFIG_FS_DAX
+	init_rwsem(&ei->dax_sem);
+#endif
 	inode_init_once(&ei->vfs_inode);
 }
 
@@ -566,6 +569,8 @@ static int parse_options(char *options, struct super_block *sb)
 			/* Fall through */
 		case Opt_dax:
 #ifdef CONFIG_FS_DAX
+			ext2_msg(sb, KERN_WARNING,
+		"DAX enabled. Warning: EXPERIMENTAL, use at your own risk");
 			set_opt(sbi->s_mount_opt, DAX);
 #else
 			ext2_msg(sb, KERN_INFO, "dax option not supported");
diff --git a/fs/ext2/xattr.c b/fs/ext2/xattr.c
index 0b6bfd3a3..fa70848af 100644
--- a/fs/ext2/xattr.c
+++ b/fs/ext2/xattr.c
@@ -293,10 +293,9 @@ bad_block:	ext2_error(inode->i_sb, "ext2_xattr_list",
 			ext2_xattr_handler(entry->e_name_index);
 
 		if (handler) {
-			size_t size = handler->list(dentry, buffer, rest,
-						    entry->e_name,
-						    entry->e_name_len,
-						    handler->flags);
+			size_t size = handler->list(handler, dentry, buffer,
+						    rest, entry->e_name,
+						    entry->e_name_len);
 			if (buffer) {
 				if (size > rest) {
 					error = -ERANGE;
diff --git a/fs/ext2/xattr_security.c b/fs/ext2/xattr_security.c
index 702fc6840..dfb087503 100644
--- a/fs/ext2/xattr_security.c
+++ b/fs/ext2/xattr_security.c
@@ -8,8 +8,9 @@
 #include "xattr.h"
 
 static size_t
-ext2_xattr_security_list(struct dentry *dentry, char *list, size_t list_size,
-			 const char *name, size_t name_len, int type)
+ext2_xattr_security_list(const struct xattr_handler *handler,
+			 struct dentry *dentry, char *list, size_t list_size,
+			 const char *name, size_t name_len)
 {
 	const int prefix_len = XATTR_SECURITY_PREFIX_LEN;
 	const size_t total_len = prefix_len + name_len + 1;
@@ -23,8 +24,9 @@ ext2_xattr_security_list(struct dentry *dentry, char *list, size_t list_size,
 }
 
 static int
-ext2_xattr_security_get(struct dentry *dentry, const char *name,
-		       void *buffer, size_t size, int type)
+ext2_xattr_security_get(const struct xattr_handler *handler,
+			struct dentry *dentry, const char *name,
+			void *buffer, size_t size)
 {
 	if (strcmp(name, "") == 0)
 		return -EINVAL;
@@ -33,8 +35,9 @@ ext2_xattr_security_get(struct dentry *dentry, const char *name,
 }
 
 static int
-ext2_xattr_security_set(struct dentry *dentry, const char *name,
-		const void *value, size_t size, int flags, int type)
+ext2_xattr_security_set(const struct xattr_handler *handler,
+			struct dentry *dentry, const char *name,
+			const void *value, size_t size, int flags)
 {
 	if (strcmp(name, "") == 0)
 		return -EINVAL;
diff --git a/fs/ext2/xattr_trusted.c b/fs/ext2/xattr_trusted.c
index 42b6e9874..3150dd3a7 100644
--- a/fs/ext2/xattr_trusted.c
+++ b/fs/ext2/xattr_trusted.c
@@ -9,8 +9,9 @@
 #include "xattr.h"
 
 static size_t
-ext2_xattr_trusted_list(struct dentry *dentry, char *list, size_t list_size,
-		const char *name, size_t name_len, int type)
+ext2_xattr_trusted_list(const struct xattr_handler *handler,
+			struct dentry *dentry, char *list, size_t list_size,
+			const char *name, size_t name_len)
 {
 	const int prefix_len = XATTR_TRUSTED_PREFIX_LEN;
 	const size_t total_len = prefix_len + name_len + 1;
@@ -27,8 +28,9 @@ ext2_xattr_trusted_list(struct dentry *dentry, char *list, size_t list_size,
 }
 
 static int
-ext2_xattr_trusted_get(struct dentry *dentry, const char *name,
-		void *buffer, size_t size, int type)
+ext2_xattr_trusted_get(const struct xattr_handler *handler,
+		       struct dentry *dentry, const char *name,
+		       void *buffer, size_t size)
 {
 	if (strcmp(name, "") == 0)
 		return -EINVAL;
@@ -37,8 +39,9 @@ ext2_xattr_trusted_get(struct dentry *dentry, const char *name,
 }
 
 static int
-ext2_xattr_trusted_set(struct dentry *dentry, const char *name,
-		const void *value, size_t size, int flags, int type)
+ext2_xattr_trusted_set(const struct xattr_handler *handler,
+		       struct dentry *dentry, const char *name,
+		       const void *value, size_t size, int flags)
 {
 	if (strcmp(name, "") == 0)
 		return -EINVAL;
diff --git a/fs/ext2/xattr_user.c b/fs/ext2/xattr_user.c
index ecdc46051..339a49bbb 100644
--- a/fs/ext2/xattr_user.c
+++ b/fs/ext2/xattr_user.c
@@ -11,8 +11,9 @@
 #include "xattr.h"
 
 static size_t
-ext2_xattr_user_list(struct dentry *dentry, char *list, size_t list_size,
-		const char *name, size_t name_len, int type)
+ext2_xattr_user_list(const struct xattr_handler *handler,
+		     struct dentry *dentry, char *list, size_t list_size,
+		     const char *name, size_t name_len)
 {
 	const size_t prefix_len = XATTR_USER_PREFIX_LEN;
 	const size_t total_len = prefix_len + name_len + 1;
@@ -29,8 +30,9 @@ ext2_xattr_user_list(struct dentry *dentry, char *list, size_t list_size,
 }
 
 static int
-ext2_xattr_user_get(struct dentry *dentry, const char *name,
-		void *buffer, size_t size, int type)
+ext2_xattr_user_get(const struct xattr_handler *handler,
+		    struct dentry *dentry, const char *name,
+		    void *buffer, size_t size)
 {
 	if (strcmp(name, "") == 0)
 		return -EINVAL;
@@ -41,8 +43,9 @@ ext2_xattr_user_get(struct dentry *dentry, const char *name,
 }
 
 static int
-ext2_xattr_user_set(struct dentry *dentry, const char *name,
-		const void *value, size_t size, int flags, int type)
+ext2_xattr_user_set(const struct xattr_handler *handler,
+		    struct dentry *dentry, const char *name,
+		    const void *value, size_t size, int flags)
 {
 	if (strcmp(name, "") == 0)
 		return -EINVAL;