1 files changed, 55 insertions, 0 deletions
diff --git a/toys/other/blkdiscard.c b/toys/other/blkdiscard.c
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--- /dev/null
+++ b/toys/other/blkdiscard.c
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+/* blkdiscard - discard device sectors
+ *
+ * Copyright 2020 Patrick Oppenlander <patrick.oppenlander@gmail.com>
+ *
+ * See http://man7.org/linux/man-pages/man8/blkdiscard.8.html
+ *
+ * The -v and -p options are not supported.
+ * Size parsing does not match util-linux where MB, GB, TB are multiples of
+ * 1000 and MiB, TiB, GiB are multipes of 1024.
+
+USE_BLKDISCARD(NEWTOY(blkdiscard, "<1>1f(force)l(length):o(offset):s(secure)z(zeroout)[!sz]", TOYFLAG_BIN))
+
+config BLKDISCARD
+  bool "blkdiscard"
+  default y
+  help
+    usage: blkdiscard [-olszf] DEVICE
+
+    Discard device sectors.
+
+    -o, --offset OFF	Byte offset to start discarding at (default 0)
+    -l, --length LEN	Bytes to discard (default all)
+    -s, --secure		Perform secure discard
+    -z, --zeroout		Zero-fill rather than discard
+    -f, --force		Disable check for mounted filesystem
+
+    OFF and LEN must be aligned to the device sector size.
+    By default entire device is discarded.
+    WARNING: All discarded data is permanently lost!
+*/
+
+#define FOR_blkdiscard
+#include "toys.h"
+
+#include <linux/fs.h>
+
+GLOBALS(
+  char *o, *l;
+)
+
+void blkdiscard_main(void)
+{
+  int fd = xopen(*toys.optargs, O_WRONLY|O_EXCL*!FLAG(f));
+  unsigned long long ol[2];
+
+  ol[0] = FLAG(o) ? atolx_range(TT.o, 0, LLONG_MAX) : 0;
+  if (FLAG(l)) ol[1] = atolx_range(TT.l, 0, LLONG_MAX);
+  else {
+    xioctl(fd, BLKGETSIZE64, ol+1);
+    ol[1] -= ol[0];
+  }
+  xioctl(fd, FLAG(s) ? BLKSECDISCARD : FLAG(z) ? BLKZEROOUT : BLKDISCARD, ol);
+
+  if (CFG_TOYBOX_FREE) close(fd);
+}