Merge branch 'release' of git://git.kernel.org/pub/scm/linux/kernel/git/lenb/linux...

[firefly-linux-kernel-4.4.55.git] / fs / ecryptfs / mmap.c

diff --git a/fs/ecryptfs/mmap.c b/fs/ecryptfs/mmap.c
index 3a6f65c3f14fc2fb26aa77df1ba8f10cae7198b7..b731b09499cb8dcc996a87772b1090bd34484a83 100644 (file)
--- a/fs/ecryptfs/mmap.c
+++ b/fs/ecryptfs/mmap.c
@@ -238,7 +238,6 @@ int ecryptfs_do_readpage(struct file *file, struct page *page,
        lower_page_data = kmap_atomic(lower_page, KM_USER1);
        memcpy(page_data, lower_page_data, PAGE_CACHE_SIZE);
        kunmap_atomic(lower_page_data, KM_USER1);
-       flush_dcache_page(lower_page);
        kunmap_atomic(page_data, KM_USER0);
        flush_dcache_page(page);
        rc = 0;
@@ -422,9 +421,11 @@ out:
        return rc;
 }
 
-static void ecryptfs_release_lower_page(struct page *lower_page)
+static
+void ecryptfs_release_lower_page(struct page *lower_page, int page_locked)
 {
-       unlock_page(lower_page);
+       if (page_locked)
+               unlock_page(lower_page);
        page_cache_release(lower_page);
 }
 
@@ -445,6 +446,7 @@ static int ecryptfs_write_inode_size_to_header(struct file *lower_file,
        const struct address_space_operations *lower_a_ops;
        u64 file_size;
 
+retry:
        header_page = grab_cache_page(lower_inode->i_mapping, 0);
        if (!header_page) {
                ecryptfs_printk(KERN_ERR, "grab_cache_page for "
@@ -454,6 +456,14 @@ static int ecryptfs_write_inode_size_to_header(struct file *lower_file,
        }
        lower_a_ops = lower_inode->i_mapping->a_ops;
        rc = lower_a_ops->prepare_write(lower_file, header_page, 0, 8);
+       if (rc) {
+               if (rc == AOP_TRUNCATED_PAGE) {
+                       ecryptfs_release_lower_page(header_page, 0);
+                       goto retry;
+               } else
+                       ecryptfs_release_lower_page(header_page, 1);
+               goto out;
+       }
        file_size = (u64)i_size_read(inode);
        ecryptfs_printk(KERN_DEBUG, "Writing size: [0x%.16x]\n", file_size);
        file_size = cpu_to_be64(file_size);
@@ -465,7 +475,11 @@ static int ecryptfs_write_inode_size_to_header(struct file *lower_file,
        if (rc < 0)
                ecryptfs_printk(KERN_ERR, "Error commiting header page "
                                "write\n");
-       ecryptfs_release_lower_page(header_page);
+       if (rc == AOP_TRUNCATED_PAGE) {
+               ecryptfs_release_lower_page(header_page, 0);
+               goto retry;
+       } else
+               ecryptfs_release_lower_page(header_page, 1);
        lower_inode->i_mtime = lower_inode->i_ctime = CURRENT_TIME;
        mark_inode_dirty_sync(inode);
 out:
@@ -491,7 +505,8 @@ static int ecryptfs_write_inode_size_to_xattr(struct inode *lower_inode,
                goto out;
        }
        lower_dentry = ecryptfs_dentry_to_lower(ecryptfs_dentry);
-       if (!lower_dentry->d_inode->i_op->getxattr) {
+       if (!lower_dentry->d_inode->i_op->getxattr ||
+                       !lower_dentry->d_inode->i_op->setxattr) {
                printk(KERN_WARNING
                       "No support for setting xattr in lower filesystem\n");
                rc = -ENOSYS;
@@ -553,6 +568,7 @@ int ecryptfs_get_lower_page(struct page **lower_page, struct inode *lower_inode,
 {
        int rc = 0;
 
+retry:
        *lower_page = grab_cache_page(lower_inode->i_mapping, lower_page_index);
        if (!(*lower_page)) {
                rc = -EINVAL;
@@ -566,15 +582,18 @@ int ecryptfs_get_lower_page(struct page **lower_page, struct inode *lower_inode,
                                                          byte_offset,
                                                          region_bytes);
        if (rc) {
-               ecryptfs_printk(KERN_ERR, "prepare_write for "
+               if (rc == AOP_TRUNCATED_PAGE) {
+                       ecryptfs_release_lower_page(*lower_page, 0);
+                       goto retry;
+               } else {
+                       ecryptfs_printk(KERN_ERR, "prepare_write for "
                                "lower_page_index = [0x%.16x] failed; rc = "
                                "[%d]\n", lower_page_index, rc);
+                       ecryptfs_release_lower_page(*lower_page, 1);
+                       (*lower_page) = NULL;
+               }
        }
 out:
-       if (rc && (*lower_page)) {
-               ecryptfs_release_lower_page(*lower_page);
-               (*lower_page) = NULL;
-       }
        return rc;
 }
 
@@ -588,16 +607,19 @@ ecryptfs_commit_lower_page(struct page *lower_page, struct inode *lower_inode,
                           struct file *lower_file, int byte_offset,
                           int region_size)
 {
+       int page_locked = 1;
        int rc = 0;
 
        rc = lower_inode->i_mapping->a_ops->commit_write(
                lower_file, lower_page, byte_offset, region_size);
+       if (rc == AOP_TRUNCATED_PAGE)
+               page_locked = 0;
        if (rc < 0) {
                ecryptfs_printk(KERN_ERR,
                                "Error committing write; rc = [%d]\n", rc);
        } else
                rc = 0;
-       ecryptfs_release_lower_page(lower_page);
+       ecryptfs_release_lower_page(lower_page, page_locked);
        return rc;
 }