[PATCH 0/4] fix bugs for ioctl EXT4_IOC_SWAP_BOOT

[PATCH 0/4] fix bugs for ioctl EXT4_IOC_SWAP_BOOT

[yangerkun]

yangerkun (4):
  ext4: fix check of inode in swap_inode_boot_loader
  ext4: cleanup pagecache before swap i_data
  ext4: update quota information while swapping boot loader inode
  ext4: add mask of ext4 flags to swap

 fs/ext4/ext4.h  |  4 ++++
 fs/ext4/ioctl.c | 73 ++++++++++++++++++++++++++++++++++++++++++++-------------
 2 files changed, 61 insertions(+), 16 deletions(-)

-- 
2.9.5

[PATCH 1/4] ext4: fix check of inode in swap_inode_boot_loader

[yangerkun]

What there need to be checked should be protected by inode lock.

Signed-off-by: yangerkun <yangerkun@huawei.com>
---
 fs/ext4/ioctl.c | 22 +++++++++++++---------
 1 file changed, 13 insertions(+), 9 deletions(-)

diff --git a/fs/ext4/ioctl.c b/fs/ext4/ioctl.c
index 0edee31..579ebe5 100644
--- a/fs/ext4/ioctl.c
+++ b/fs/ext4/ioctl.c
@@ -116,15 +116,6 @@ static long swap_inode_boot_loader(struct super_block *sb,
 	struct inode *inode_bl;
 	struct ext4_inode_info *ei_bl;
 
-	if (inode->i_nlink != 1 || !S_ISREG(inode->i_mode) ||
-	    IS_SWAPFILE(inode) || IS_ENCRYPTED(inode) ||
-	    ext4_has_inline_data(inode))
-		return -EINVAL;
-
-	if (IS_RDONLY(inode) || IS_APPEND(inode) || IS_IMMUTABLE(inode) ||
-	    !inode_owner_or_capable(inode) || !capable(CAP_SYS_ADMIN))
-		return -EPERM;
-
 	inode_bl = ext4_iget(sb, EXT4_BOOT_LOADER_INO);
 	if (IS_ERR(inode_bl))
 		return PTR_ERR(inode_bl);
@@ -137,6 +128,19 @@ static long swap_inode_boot_loader(struct super_block *sb,
 	 * that only 1 swap_inode_boot_loader is running. */
 	lock_two_nondirectories(inode, inode_bl);
 
+	if (inode->i_nlink != 1 || !S_ISREG(inode->i_mode) ||
+	    IS_SWAPFILE(inode) || IS_ENCRYPTED(inode) ||
+	    ext4_has_inline_data(inode)) {
+		err = -EINVAL;
+		goto journal_err_out;
+	}
+
+	if (IS_RDONLY(inode) || IS_APPEND(inode) || IS_IMMUTABLE(inode) ||
+	    !inode_owner_or_capable(inode) || !capable(CAP_SYS_ADMIN)) {
+		err = -EPERM;
+		goto journal_err_out;
+	}
+
 	/* Wait for all existing dio workers */
 	inode_dio_wait(inode);
 	inode_dio_wait(inode_bl);
-- 
2.9.5

[PATCH 2/4] ext4: cleanup pagecache before swap i_data

[yangerkun]

Make sure new dirty page will not appear.

Signed-off-by: yangerkun <yangerkun@huawei.com>
---
 fs/ext4/ioctl.c | 16 ++++++++++++----
 1 file changed, 12 insertions(+), 4 deletions(-)

diff --git a/fs/ext4/ioctl.c b/fs/ext4/ioctl.c
index 579ebe5..fdfada3 100644
--- a/fs/ext4/ioctl.c
+++ b/fs/ext4/ioctl.c
@@ -121,9 +121,6 @@ static long swap_inode_boot_loader(struct super_block *sb,
 		return PTR_ERR(inode_bl);
 	ei_bl = EXT4_I(inode_bl);
 
-	filemap_flush(inode->i_mapping);
-	filemap_flush(inode_bl->i_mapping);
-
 	/* Protect orig inodes against a truncate and make sure,
 	 * that only 1 swap_inode_boot_loader is running. */
 	lock_two_nondirectories(inode, inode_bl);
@@ -141,6 +138,15 @@ static long swap_inode_boot_loader(struct super_block *sb,
 		goto journal_err_out;
 	}
 
+	down_write(&EXT4_I(inode)->i_mmap_sem);
+	err = filemap_write_and_wait(inode->i_mapping);
+	if (err)
+		goto err_out;
+
+	err = filemap_write_and_wait(inode_bl->i_mapping);
+	if (err)
+		goto err_out;
+
 	/* Wait for all existing dio workers */
 	inode_dio_wait(inode);
 	inode_dio_wait(inode_bl);
@@ -151,7 +157,7 @@ static long swap_inode_boot_loader(struct super_block *sb,
 	handle = ext4_journal_start(inode_bl, EXT4_HT_MOVE_EXTENTS, 2);
 	if (IS_ERR(handle)) {
 		err = -EINVAL;
-		goto journal_err_out;
+		goto err_out;
 	}
 
 	/* Protect extent tree against block allocations via delalloc */
@@ -208,6 +214,8 @@ static long swap_inode_boot_loader(struct super_block *sb,
 	ext4_journal_stop(handle);
 	ext4_double_up_write_data_sem(inode, inode_bl);
 
+err_out:
+	up_write(&EXT4_I(inode)->i_mmap_sem);
 journal_err_out:
 	unlock_two_nondirectories(inode, inode_bl);
 	iput(inode_bl);
-- 
2.9.5

[PATCH 3/4] ext4: update quota information while swapping boot loader inode

[yangerkun]

The quota information should also be update.

Signed-off-by: yangerkun <yangerkun@huawei.com>
---
 fs/ext4/ioctl.c | 29 +++++++++++++++++++++++++++--
 1 file changed, 27 insertions(+), 2 deletions(-)

diff --git a/fs/ext4/ioctl.c b/fs/ext4/ioctl.c
index fdfada3..60d406f 100644
--- a/fs/ext4/ioctl.c
+++ b/fs/ext4/ioctl.c
@@ -63,13 +63,14 @@ static void swap_inode_data(struct inode *inode1, struct inode *inode2)
 	loff_t isize;
 	struct ext4_inode_info *ei1;
 	struct ext4_inode_info *ei2;
+	struct inode *big_inode;
+	struct inode *small_inode;
+	qsize_t size1, size2, diff;
 
 	ei1 = EXT4_I(inode1);
 	ei2 = EXT4_I(inode2);
 
 	swap(inode1->i_version, inode2->i_version);
-	swap(inode1->i_blocks, inode2->i_blocks);
-	swap(inode1->i_bytes, inode2->i_bytes);
 	swap(inode1->i_atime, inode2->i_atime);
 	swap(inode1->i_mtime, inode2->i_mtime);
 
@@ -79,6 +80,21 @@ static void swap_inode_data(struct inode *inode1, struct inode *inode2)
 	ext4_es_remove_extent(inode1, 0, EXT_MAX_BLOCKS);
 	ext4_es_remove_extent(inode2, 0, EXT_MAX_BLOCKS);
 
+	size1 = (qsize_t)(inode1->i_blocks) * (1 << 9) + inode1->i_bytes;
+	size2 = (qsize_t)(inode2->i_blocks) * (1 << 9) + inode2->i_bytes;
+	if (size1 > size2) {
+		big_inode = inode1;
+		small_inode = inode2;
+		diff = size1 - size2;
+	} else {
+		big_inode = inode2;
+		small_inode = inode1;
+		diff = size2 - size1;
+	}
+
+	dquot_alloc_space_nofail(small_inode, diff);
+	dquot_free_space(big_inode, diff);
+
 	isize = i_size_read(inode1);
 	i_size_write(inode1, i_size_read(inode2));
 	i_size_write(inode2, isize);
@@ -180,6 +196,14 @@ static long swap_inode_boot_loader(struct super_block *sb,
 			memset(ei_bl->i_data, 0, sizeof(ei_bl->i_data));
 	}
 
+	err = dquot_initialize(inode);
+	if (err)
+		goto err_out1;
+
+	err = dquot_initialize(inode_bl);
+	if (err)
+		goto err_out1;
+
 	swap_inode_data(inode, inode_bl);
 
 	inode->i_ctime = inode_bl->i_ctime = current_time(inode);
@@ -211,6 +235,7 @@ static long swap_inode_boot_loader(struct super_block *sb,
 			ext4_mark_inode_dirty(handle, inode_bl);
 		}
 	}
+err_out1:
 	ext4_journal_stop(handle);
 	ext4_double_up_write_data_sem(inode, inode_bl);
 
-- 
2.9.5

[PATCH 4/4] ext4: add mask of ext4 flags to swap

[yangerkun]

Not all flags should be swap, add a mask to do this.

Signed-off-by: yangerkun <yangerkun@huawei.com>
---
 fs/ext4/ext4.h  | 4 ++++
 fs/ext4/ioctl.c | 6 +++++-
 2 files changed, 9 insertions(+), 1 deletion(-)

diff --git a/fs/ext4/ext4.h b/fs/ext4/ext4.h
index 3f89d0a..b438a7c 100644
--- a/fs/ext4/ext4.h
+++ b/fs/ext4/ext4.h
@@ -426,6 +426,10 @@ struct flex_groups {
 /* Flags that are appropriate for non-directories/regular files. */
 #define EXT4_OTHER_FLMASK (EXT4_NODUMP_FL | EXT4_NOATIME_FL)
 
+/* Flags that should be swap */
+#define EXT4_FL_SHOULD_SWAP (EXT4_COMPR_FL | EXT4_COMPRBLK_FL | EXT4_NOCOMPR_FL |\
+			EXT4_HUGE_FILE_FL | EXT4_EXTENTS_FL)
+
 /* Mask out flags that are inappropriate for the given type of inode. */
 static inline __u32 ext4_mask_flags(umode_t mode, __u32 flags)
 {
diff --git a/fs/ext4/ioctl.c b/fs/ext4/ioctl.c
index 60d406f..53e26a6 100644
--- a/fs/ext4/ioctl.c
+++ b/fs/ext4/ioctl.c
@@ -66,6 +66,7 @@ static void swap_inode_data(struct inode *inode1, struct inode *inode2)
 	struct inode *big_inode;
 	struct inode *small_inode;
 	qsize_t size1, size2, diff;
+	unsigned long tmp;
 
 	ei1 = EXT4_I(inode1);
 	ei2 = EXT4_I(inode2);
@@ -75,7 +76,10 @@ static void swap_inode_data(struct inode *inode1, struct inode *inode2)
 	swap(inode1->i_mtime, inode2->i_mtime);
 
 	memswap(ei1->i_data, ei2->i_data, sizeof(ei1->i_data));
-	swap(ei1->i_flags, ei2->i_flags);
+	tmp = ei1->i_flags & EXT4_FL_SHOULD_SWAP;
+	ei1->i_flags = (ei2->i_flags & EXT4_FL_SHOULD_SWAP) |
+		(ei1->i_flags & ~EXT4_FL_SHOULD_SWAP);
+	ei2->i_flags = tmp | (ei2->i_flags & ~EXT4_FL_SHOULD_SWAP);
 	swap(ei1->i_disksize, ei2->i_disksize);
 	ext4_es_remove_extent(inode1, 0, EXT_MAX_BLOCKS);
 	ext4_es_remove_extent(inode2, 0, EXT_MAX_BLOCKS);
-- 
2.9.5