summaryrefslogtreecommitdiffstats
diff options
context:
space:
mode:
-rw-r--r--fs/fs-writeback.c7
-rw-r--r--fs/sync.c7
-rw-r--r--include/linux/fs.h1
-rw-r--r--mm/filemap.c67
4 files changed, 67 insertions, 15 deletions
diff --git a/fs/fs-writeback.c b/fs/fs-writeback.c
index 7378169..206a68b 100644
--- a/fs/fs-writeback.c
+++ b/fs/fs-writeback.c
@@ -2149,7 +2149,12 @@ static void wait_sb_inodes(struct super_block *sb)
iput(old_inode);
old_inode = inode;
- filemap_fdatawait(mapping);
+ /*
+ * We keep the error status of individual mapping so that
+ * applications can catch the writeback error using fsync(2).
+ * See filemap_fdatawait_keep_errors() for details.
+ */
+ filemap_fdatawait_keep_errors(mapping);
cond_resched();
diff --git a/fs/sync.c b/fs/sync.c
index fbc98ee..4ec430a 100644
--- a/fs/sync.c
+++ b/fs/sync.c
@@ -86,7 +86,12 @@ static void fdatawrite_one_bdev(struct block_device *bdev, void *arg)
static void fdatawait_one_bdev(struct block_device *bdev, void *arg)
{
- filemap_fdatawait(bdev->bd_inode->i_mapping);
+ /*
+ * We keep the error status of individual mapping so that
+ * applications can catch the writeback error using fsync(2).
+ * See filemap_fdatawait_keep_errors() for details.
+ */
+ filemap_fdatawait_keep_errors(bdev->bd_inode->i_mapping);
}
/*
diff --git a/include/linux/fs.h b/include/linux/fs.h
index 72d8a84..9355f37 100644
--- a/include/linux/fs.h
+++ b/include/linux/fs.h
@@ -2422,6 +2422,7 @@ extern int write_inode_now(struct inode *, int);
extern int filemap_fdatawrite(struct address_space *);
extern int filemap_flush(struct address_space *);
extern int filemap_fdatawait(struct address_space *);
+extern void filemap_fdatawait_keep_errors(struct address_space *);
extern int filemap_fdatawait_range(struct address_space *, loff_t lstart,
loff_t lend);
extern int filemap_write_and_wait(struct address_space *mapping);
diff --git a/mm/filemap.c b/mm/filemap.c
index 1fe962b..884766d 100644
--- a/mm/filemap.c
+++ b/mm/filemap.c
@@ -331,23 +331,14 @@ int filemap_flush(struct address_space *mapping)
}
EXPORT_SYMBOL(filemap_flush);
-/**
- * filemap_fdatawait_range - wait for writeback to complete
- * @mapping: address space structure to wait for
- * @start_byte: offset in bytes where the range starts
- * @end_byte: offset in bytes where the range ends (inclusive)
- *
- * Walk the list of under-writeback pages of the given address space
- * in the given range and wait for all of them.
- */
-int filemap_fdatawait_range(struct address_space *mapping, loff_t start_byte,
- loff_t end_byte)
+static int __filemap_fdatawait_range(struct address_space *mapping,
+ loff_t start_byte, loff_t end_byte)
{
pgoff_t index = start_byte >> PAGE_CACHE_SHIFT;
pgoff_t end = end_byte >> PAGE_CACHE_SHIFT;
struct pagevec pvec;
int nr_pages;
- int ret2, ret = 0;
+ int ret = 0;
if (end_byte < start_byte)
goto out;
@@ -374,6 +365,29 @@ int filemap_fdatawait_range(struct address_space *mapping, loff_t start_byte,
cond_resched();
}
out:
+ return ret;
+}
+
+/**
+ * filemap_fdatawait_range - wait for writeback to complete
+ * @mapping: address space structure to wait for
+ * @start_byte: offset in bytes where the range starts
+ * @end_byte: offset in bytes where the range ends (inclusive)
+ *
+ * Walk the list of under-writeback pages of the given address space
+ * in the given range and wait for all of them. Check error status of
+ * the address space and return it.
+ *
+ * Since the error status of the address space is cleared by this function,
+ * callers are responsible for checking the return value and handling and/or
+ * reporting the error.
+ */
+int filemap_fdatawait_range(struct address_space *mapping, loff_t start_byte,
+ loff_t end_byte)
+{
+ int ret, ret2;
+
+ ret = __filemap_fdatawait_range(mapping, start_byte, end_byte);
ret2 = filemap_check_errors(mapping);
if (!ret)
ret = ret2;
@@ -383,11 +397,38 @@ out:
EXPORT_SYMBOL(filemap_fdatawait_range);
/**
+ * filemap_fdatawait_keep_errors - wait for writeback without clearing errors
+ * @mapping: address space structure to wait for
+ *
+ * Walk the list of under-writeback pages of the given address space
+ * and wait for all of them. Unlike filemap_fdatawait(), this function
+ * does not clear error status of the address space.
+ *
+ * Use this function if callers don't handle errors themselves. Expected
+ * call sites are system-wide / filesystem-wide data flushers: e.g. sync(2),
+ * fsfreeze(8)
+ */
+void filemap_fdatawait_keep_errors(struct address_space *mapping)
+{
+ loff_t i_size = i_size_read(mapping->host);
+
+ if (i_size == 0)
+ return;
+
+ __filemap_fdatawait_range(mapping, 0, i_size - 1);
+}
+
+/**
* filemap_fdatawait - wait for all under-writeback pages to complete
* @mapping: address space structure to wait for
*
* Walk the list of under-writeback pages of the given address space
- * and wait for all of them.
+ * and wait for all of them. Check error status of the address space
+ * and return it.
+ *
+ * Since the error status of the address space is cleared by this function,
+ * callers are responsible for checking the return value and handling and/or
+ * reporting the error.
*/
int filemap_fdatawait(struct address_space *mapping)
{
OpenPOWER on IntegriCloud