We actually don't need to issue trim on entire disk by checking first
blocks having zeros.
Signed-off-by: Jaegeuk Kim <jaeg...@kernel.org>
---
v2 from v1:
- clean up
mkfs/f2fs_format_utils.c | 53 ++++++++++++++++++++++++++++++++++++++--
1 file changed, 51 insertions(+), 2 deletions(-)
diff --git a/mkfs/f2fs_format_utils.c b/mkfs/f2fs_format_utils.c
index 8bf128c..f2d55ad 100644
--- a/mkfs/f2fs_format_utils.c
+++ b/mkfs/f2fs_format_utils.c
@@ -25,6 +25,7 @@
#include <stdio.h>
#include <unistd.h>
#include <stdlib.h>
+#include <stdbool.h>
#ifndef ANDROID_WINDOWS_HOST
#include <sys/ioctl.h>
#endif
@@ -110,13 +111,61 @@ static int trim_device(int i)
return 0;
}
+static bool is_wiped_device(int i)
+{
+#ifdef WITH_ANDROID
+ struct device_info *dev = c.devices + i;
+ int fd = dev->fd;
+ char *buf, *zero_buf;
+ bool wiped = true;
+ int nblocks = 4096; /* 16MB size */
+ int j;
+
+ buf = malloc(F2FS_BLKSIZE);
+ if (buf == NULL) {
+ MSG(1, "\tError: Malloc Failed for buf!!!\n");
+ return false;
+ }
+ zero_buf = calloc(1, F2FS_BLKSIZE);
+ if (zero_buf == NULL) {
+ MSG(1, "\tError: Calloc Failed for zero buf!!!\n");
+ free(buf);
+ return false;
+ }
+
+ if (lseek(fd, 0, SEEK_SET) < 0) {
+ free(zero_buf);
+ free(buf);
+ return false;
+ }
+
+ /* check first n blocks */
+ for (j = 0; j < nblocks; j++) {
+ if (read(fd, buf, F2FS_BLKSIZE) != F2FS_BLKSIZE ||
+ memcmp(buf, zero_buf, F2FS_BLKSIZE)) {
+ wiped = false;
+ break;
+ }
+ }
+ free(zero_buf);
+ free(buf);
+
+ if (wiped)
+ MSG(0, "Info: Found all zeros in first %d blocks\n", nblocks);
+ return wiped;
+#else
+ return false;
+#endif
+}
+
int f2fs_trim_devices(void)
{
int i;
- for (i = 0; i < c.ndevs; i++)
- if (trim_device(i))
+ for (i = 0; i < c.ndevs; i++) {
+ if (!is_wiped_device(i) && trim_device(i))
return -1;
+ }
c.trimmed = 1;
return 0;
}
--
2.19.0.605.g01d371f741-goog
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