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>
---
mkfs/f2fs_format_utils.c | 47 ++++++++++++++++++++++++++++++++++++++--
1 file changed, 45 insertions(+), 2 deletions(-)
diff --git a/mkfs/f2fs_format_utils.c b/mkfs/f2fs_format_utils.c
index 8bf128c..52fedc7 100644
--- a/mkfs/f2fs_format_utils.c
+++ b/mkfs/f2fs_format_utils.c
@@ -110,13 +110,56 @@ static int trim_device(int i)
return 0;
}
+static int f2fs_zero_blocks(int i)
+{
+#ifdef WITH_ANDROID
+ struct device_info *dev = c.devices + i;
+ int fd = dev->fd;
+ char buf[F2FS_BLKSIZE];
+ char *zero_buf;
+ int j, ret;
+ int ret2 = 0;
+
+ zero_buf = calloc(1, F2FS_BLKSIZE);
+ if (zero_buf == NULL) {
+ MSG(1, "\tError: Malloc Failed for zero buf!!!\n");
+ return -1;
+ }
+
+ /* check first 16MB blocks */
+ for (j = 0; j < 4096; j++) {
+ ret = lseek(fd, j * F2FS_BLKSIZE, SEEK_SET);
+ if (ret < 0) {
+ ret2 = -1;
+ break;
+ }
+ ret = read(fd, buf, F2FS_BLKSIZE);
+ if (ret != F2FS_BLKSIZE) {
+ ret2 = -1;
+ break;
+ }
+ if (memcmp(buf, zero_buf, F2FS_BLKSIZE)) {
+ ret2 = -1;
+ break;
+ }
+ }
+ free(zero_buf);
+ if (!ret2)
+ MSG(0, "Info: Skip discarding blocks (found all zeros\n");
+ return ret2;
+#else
+ return -1;
+#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 (f2fs_zero_blocks(i) && trim_device(i))
return -1;
+ }
c.trimmed = 1;
return 0;
}
--
2.19.0.605.g01d371f741-goog
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