From e5b401d4bf67a1704f28872d3abe09eaf65cdabe Mon Sep 17 00:00:00 2001
From: Jens Axboe <jens.axboe@oracle.com>
Date: Wed, 18 Oct 2006 16:03:40 +0200
Subject: [PATCH] [PATCH] Sync and invalidate cache prior to running verify

Make sure we re-read the contents from disk, not from memory.

Signed-off-by: Jens Axboe <jens.axboe@oracle.com>
---
 filesetup.c  | 40 ++++++++++++++++++++++++++++------------
 fio.c        | 11 ++++++++++-
 fio.h        |  1 +
 os-freebsd.h |  7 ++++++-
 os-linux.h   | 12 ++++++++++++
 os-solaris.h |  7 ++++++-
 6 files changed, 63 insertions(+), 15 deletions(-)

diff --git a/filesetup.c b/filesetup.c
index 04052bf3..4f3d6cdf 100644
--- a/filesetup.c
+++ b/filesetup.c
@@ -183,6 +183,30 @@ static int get_file_size(struct thread_data *td, struct fio_file *f)
 	return 0;
 }
 
+int file_invalidate_cache(struct thread_data *td, struct fio_file *f)
+{
+	int ret = 0;
+
+	/*
+	 * FIXME: add blockdev flushing too
+	 */
+	if (td->io_ops->flags & FIO_MMAPIO)
+		ret = madvise(f->mmap, f->file_size, MADV_DONTNEED);
+	else if (td->filetype == FIO_TYPE_FILE)
+		ret = fadvise(f->fd, f->file_offset, f->file_size, POSIX_FADV_DONTNEED);
+	else if (td->filetype == FIO_TYPE_BD)
+		ret = blockdev_invalidate_cache(f->fd);
+	else if (td->filetype == FIO_TYPE_CHAR)
+		ret = 0;
+
+	if (ret < 0) {
+		td_verror(td, errno);
+		return 1;
+	}
+
+	return 0;
+}
+
 static int __setup_file_mmap(struct thread_data *td, struct fio_file *f)
 {
 	int flags;
@@ -204,12 +228,8 @@ static int __setup_file_mmap(struct thread_data *td, struct fio_file *f)
 		return 1;
 	}
 
-	if (td->invalidate_cache) {
-		if (madvise(f->mmap, f->file_size, MADV_DONTNEED) < 0) {
-			td_verror(td, errno);
-			return 1;
-		}
-	}
+	if (td->invalidate_cache && file_invalidate_cache(td, f))
+		return 1;
 
 	if (td->sequential) {
 		if (madvise(f->mmap, f->file_size, MADV_SEQUENTIAL) < 0) {
@@ -242,12 +262,8 @@ static int setup_files_mmap(struct thread_data *td)
 
 static int __setup_file_plain(struct thread_data *td, struct fio_file *f)
 {
-	if (td->invalidate_cache) {
-		if (fadvise(f->fd, f->file_offset, f->file_size, POSIX_FADV_DONTNEED) < 0) {
-			td_verror(td, errno);
-			return 1;
-		}
-	}
+	if (td->invalidate_cache && file_invalidate_cache(td, f))
+		return 1;
 
 	if (td->sequential) {
 		if (fadvise(f->fd, f->file_offset, f->file_size, POSIX_FADV_SEQUENTIAL) < 0) {
diff --git a/fio.c b/fio.c
index 2b760ddd..5432e383 100644
--- a/fio.c
+++ b/fio.c
@@ -563,7 +563,16 @@ void do_verify(struct thread_data *td)
 	struct io_u *io_u, *v_io_u = NULL;
 	struct io_completion_data icd;
 	struct fio_file *f;
-	int ret;
+	int ret, i;
+
+	/*
+	 * sync io first and invalidate cache, to make sure we really
+	 * read from disk.
+	 */
+	for_each_file(td, f, i) {
+		td_io_sync(td, f);
+		file_invalidate_cache(td, f);
+	}
 
 	td_set_runstate(td, TD_VERIFYING);
 
diff --git a/fio.h b/fio.h
index e279574a..6ecb11cf 100644
--- a/fio.h
+++ b/fio.h
@@ -448,6 +448,7 @@ extern int init_random_state(struct thread_data *);
  */
 extern void close_files(struct thread_data *);
 extern int setup_files(struct thread_data *);
+extern int file_invalidate_cache(struct thread_data *, struct fio_file *);
 
 /*
  * ETA/status stuff
diff --git a/os-freebsd.h b/os-freebsd.h
index 6a4c11b6..01c5ce91 100644
--- a/os-freebsd.h
+++ b/os-freebsd.h
@@ -21,7 +21,12 @@ typedef unsigned int os_random_state_t;
  */
 static inline int blockdev_size(int fd, unsigned long long *bytes)
 {
-	return 1;
+	return EINVAL;
+}
+
+static inline int blockdev_invalidate_cache(int fd)
+{
+	return EINVAL;
 }
 
 static inline unsigned long long os_phys_mem(void)
diff --git a/os-linux.h b/os-linux.h
index 4c54c8cc..752d17e1 100644
--- a/os-linux.h
+++ b/os-linux.h
@@ -84,6 +84,18 @@ enum {
 #define BLKGETSIZE64	_IOR(0x12,114,size_t)
 #endif
 
+#ifndef BLKFLSBUF
+#define BLKFLSBUF	_IO(0x12,97)
+#endif
+
+static inline int blockdev_invalidate_cache(int fd)
+{
+	if (!ioctl(fd, BLKFLSBUF))
+		return 0;
+
+	return errno;
+}
+
 static inline int blockdev_size(int fd, unsigned long long *bytes)
 {
 	if (!ioctl(fd, BLKGETSIZE64, bytes))
diff --git a/os-solaris.h b/os-solaris.h
index e7f4e4ee..898da18e 100644
--- a/os-solaris.h
+++ b/os-solaris.h
@@ -19,7 +19,12 @@ typedef unsigned int os_random_state_t;
  */
 static inline int blockdev_size(int fd, unsigned long long *bytes)
 {
-	return 1;
+	return EINVAL;
+}
+
+static inline int blockdev_invalidate_cache(int fd)
+{
+	return EINVAL;
 }
 
 static inline unsigned long long os_phys_mem(void)
-- 
2.25.1