From: Daeho Jeong <daehoje...@google.com>
Added a new ioctl to send discard commands or/and zero out
to selected data area of a regular file for security reason.
Signed-off-by: Daeho Jeong <daehoje...@google.com>
Reviewed-by: Chao Yu <yuch...@huawei.com>
Signed-off-by: Jaegeuk Kim <jaeg...@kernel.org>
---
fs/f2fs/f2fs.h | 15 ++++
fs/f2fs/file.c | 181 +++++++++++++++++++++++++++++++++++++++++++++++++
2 files changed, 196 insertions(+)
diff --git a/fs/f2fs/f2fs.h b/fs/f2fs/f2fs.h
index b35a50f4953c..917fb2f63cd7 100644
--- a/fs/f2fs/f2fs.h
+++ b/fs/f2fs/f2fs.h
@@ -434,6 +434,8 @@ static inline bool __has_cursum_space(struct f2fs_journal
*journal,
_IOR(F2FS_IOCTL_MAGIC, 18, __u64)
#define F2FS_IOC_RESERVE_COMPRESS_BLOCKS \
_IOR(F2FS_IOCTL_MAGIC, 19, __u64)
+#define F2FS_IOC_SEC_TRIM_FILE _IOW(F2FS_IOCTL_MAGIC, 20, \
+ struct f2fs_sectrim_range)
#define F2FS_IOC_GET_VOLUME_NAME FS_IOC_GETFSLABEL
#define F2FS_IOC_SET_VOLUME_NAME FS_IOC_SETFSLABEL
@@ -453,6 +455,13 @@ static inline bool __has_cursum_space(struct f2fs_journal
*journal,
#define F2FS_GOING_DOWN_METAFLUSH 0x3 /* going down with meta flush */
#define F2FS_GOING_DOWN_NEED_FSCK 0x4 /* going down to trigger fsck */
+/*
+ * Flags used by F2FS_IOC_SEC_TRIM_FILE
+ */
+#define F2FS_TRIM_FILE_DISCARD 0x1 /* send discard command */
+#define F2FS_TRIM_FILE_ZEROOUT 0x2 /* zero out */
+#define F2FS_TRIM_FILE_MASK 0x3
+
#if defined(__KERNEL__) && defined(CONFIG_COMPAT)
/*
* ioctl commands in 32 bit emulation
@@ -488,6 +497,12 @@ struct f2fs_flush_device {
u32 segments; /* # of segments to flush */
};
+struct f2fs_sectrim_range {
+ u64 start;
+ u64 len;
+ u64 flags;
+};
+
/* for inline stuff */
#define DEF_INLINE_RESERVED_SIZE 1
static inline int get_extra_isize(struct inode *inode);
diff --git a/fs/f2fs/file.c b/fs/f2fs/file.c
index 98721f9bef25..41d057ffa8c3 100644
--- a/fs/f2fs/file.c
+++ b/fs/f2fs/file.c
@@ -21,6 +21,7 @@
#include <linux/uuid.h>
#include <linux/file.h>
#include <linux/nls.h>
+#include <linux/sched/signal.h>
#include "f2fs.h"
#include "node.h"
@@ -3754,6 +3755,183 @@ static int f2fs_reserve_compress_blocks(struct file
*filp, unsigned long arg)
return ret;
}
+static int f2fs_secure_erase(struct block_device *bdev, block_t block,
+ block_t len, u32 flags)
+{
+ struct request_queue *q = bdev_get_queue(bdev);
+ sector_t sector = SECTOR_FROM_BLOCK(block);
+ sector_t nr_sects = SECTOR_FROM_BLOCK(len);
+ int ret = 0;
+
+ if (!q)
+ return -ENXIO;
+
+ if (flags & F2FS_TRIM_FILE_DISCARD)
+ ret = blkdev_issue_discard(bdev, sector, nr_sects, GFP_NOFS,
+ blk_queue_secure_erase(q) ?
+ BLKDEV_DISCARD_SECURE : 0);
+
+ if (!ret && (flags & F2FS_TRIM_FILE_ZEROOUT))
+ ret = blkdev_issue_zeroout(bdev, sector, nr_sects, GFP_NOFS, 0);
+
+ return ret;
+}
+
+static int f2fs_sec_trim_file(struct file *filp, unsigned long arg)
+{
+ struct inode *inode = file_inode(filp);
+ struct f2fs_sb_info *sbi = F2FS_I_SB(inode);
+ struct address_space *mapping = inode->i_mapping;
+ struct block_device *prev_bdev = NULL;
+ struct f2fs_sectrim_range range;
+ pgoff_t index, pg_end;
+ block_t prev_block = 0, len = 0;
+ loff_t end_addr;
+ bool to_end;
+ int ret = 0;
+
+ if (!(filp->f_mode & FMODE_WRITE))
+ return -EBADF;
+
+ if (copy_from_user(&range, (struct f2fs_sectrim_range __user *)arg,
+ sizeof(range)))
+ return -EFAULT;
+
+ if (range.flags == 0 || (range.flags & ~F2FS_TRIM_FILE_MASK) ||
+ !S_ISREG(inode->i_mode))
+ return -EINVAL;
+
+ if ((range.flags & F2FS_TRIM_FILE_DISCARD) &&
+ !f2fs_hw_support_discard(sbi))
+ return -EOPNOTSUPP;
+
+ file_start_write(filp);
+ inode_lock(inode);
+
+ if (f2fs_is_atomic_file(inode) || f2fs_compressed_file(inode)) {
+ ret = -EINVAL;
+ goto err;
+ }
+
+ if (range.start >= inode->i_size) {
+ ret = -EINVAL;
+ goto err;
+ }
+
+ if (inode->i_size - range.start < range.len) {
+ ret = -E2BIG;
+ goto err;
+ }
+ end_addr = range.start + range.len;
+
+ to_end = (end_addr == inode->i_size);
+ if (!IS_ALIGNED(range.start, F2FS_BLKSIZE) ||
+ (!to_end && !IS_ALIGNED(end_addr, F2FS_BLKSIZE))) {
+ ret = -EINVAL;
+ goto err;
+ }
+
+ index = F2FS_BYTES_TO_BLK(range.start);
+ pg_end = DIV_ROUND_UP(end_addr, F2FS_BLKSIZE);
+
+ ret = f2fs_convert_inline_inode(inode);
+ if (ret)
+ goto err;
+
+ down_write(&F2FS_I(inode)->i_gc_rwsem[WRITE]);
+ down_write(&F2FS_I(inode)->i_mmap_sem);
+
+ ret = filemap_write_and_wait_range(mapping, range.start, end_addr - 1);
+ if (ret)
+ goto out;
+
+ truncate_inode_pages_range(mapping, range.start,
+ to_end ? -1 : end_addr - 1);
+
+ while (index < pg_end) {
+ struct dnode_of_data dn;
+ pgoff_t end_offset, count;
+ int i;
+
+ set_new_dnode(&dn, inode, NULL, NULL, 0);
+ ret = f2fs_get_dnode_of_data(&dn, index, LOOKUP_NODE);
+ if (ret) {
+ if (ret == -ENOENT) {
+ index = f2fs_get_next_page_offset(&dn, index);
+ continue;
+ }
+ goto out;
+ }
+
+ end_offset = ADDRS_PER_PAGE(dn.node_page, inode);
+ count = min(end_offset - dn.ofs_in_node, pg_end - index);
+ for (i = 0; i < count; i++, dn.ofs_in_node++) {
+ struct block_device *cur_bdev;
+ block_t blkaddr = f2fs_data_blkaddr(&dn);
+
+ if (!__is_valid_data_blkaddr(blkaddr))
+ continue;
+
+ if (!f2fs_is_valid_blkaddr(sbi, blkaddr,
+ DATA_GENERIC_ENHANCE)) {
+ ret = -EFSCORRUPTED;
+ f2fs_put_dnode(&dn);
+ goto out;
+ }
+
+ cur_bdev = f2fs_target_device(sbi, blkaddr, NULL);
+ if (f2fs_is_multi_device(sbi)) {
+ int di = f2fs_target_device_index(sbi, blkaddr);
+
+ blkaddr -= FDEV(di).start_blk;
+ }
+
+ if (len) {
+ if (prev_bdev == cur_bdev &&
+ blkaddr == prev_block + len) {
+ len++;
+ } else {
+ ret = f2fs_secure_erase(prev_bdev,
+ prev_block, len, range.flags);
+ if (ret) {
+ f2fs_put_dnode(&dn);
+ goto out;
+ }
+
+ len = 0;
+ }
+ }
+
+ if (!len) {
+ prev_bdev = cur_bdev;
+ prev_block = blkaddr;
+ len = 1;
+ }
+ }
+
+ f2fs_put_dnode(&dn);
+ index += count;
+
+ if (fatal_signal_pending(current)) {
+ ret = -EINTR;
+ goto out;
+ }
+ cond_resched();
+ }
+
+ if (len)
+ ret = f2fs_secure_erase(prev_bdev, prev_block, len,
+ range.flags);
+out:
+ up_write(&F2FS_I(inode)->i_mmap_sem);
+ up_write(&F2FS_I(inode)->i_gc_rwsem[WRITE]);
+err:
+ inode_unlock(inode);
+ file_end_write(filp);
+
+ return ret;
+}
+
long f2fs_ioctl(struct file *filp, unsigned int cmd, unsigned long arg)
{
if (unlikely(f2fs_cp_error(F2FS_I_SB(file_inode(filp)))))
@@ -3840,6 +4018,8 @@ long f2fs_ioctl(struct file *filp, unsigned int cmd,
unsigned long arg)
return f2fs_release_compress_blocks(filp, arg);
case F2FS_IOC_RESERVE_COMPRESS_BLOCKS:
return f2fs_reserve_compress_blocks(filp, arg);
+ case F2FS_IOC_SEC_TRIM_FILE:
+ return f2fs_sec_trim_file(filp, arg);
default:
return -ENOTTY;
}
@@ -4009,6 +4189,7 @@ long f2fs_compat_ioctl(struct file *file, unsigned int
cmd, unsigned long arg)
case F2FS_IOC_GET_COMPRESS_BLOCKS:
case F2FS_IOC_RELEASE_COMPRESS_BLOCKS:
case F2FS_IOC_RESERVE_COMPRESS_BLOCKS:
+ case F2FS_IOC_SEC_TRIM_FILE:
break;
default:
return -ENOIOCTLCMD;
--
2.27.0.383.g050319c2ae-goog
