blkdiscard: add --zeroout (BLKZEROOUT ioctl)

Requested-by: Yaniv Kaul <ykaul@redhat.com>
Signed-off-by: Karel Zak <kzak@redhat.com>

diff --git a/sys-utils/blkdiscard.8 b/sys-utils/blkdiscard.8
index f79fecb330e629cf6c6a6c47e96dfab102050368..71180e9063a469517862e5da262b4879705684f7 100644 (file)
--- a/sys-utils/blkdiscard.8
+++ b/sys-utils/blkdiscard.8
@@ -3,12 +3,11 @@
 blkdiscard \- discard sectors on a device
 .SH SYNOPSIS
 .B blkdiscard
+[options]
 .RB [ \-o
 .IR offset ]
 .RB [ \-l
 .IR length ]
-.RB [ \-s ]
-.RB [ \-v ]
 .I device
 .SH DESCRIPTION
 .B blkdiscard
@@ -58,6 +57,9 @@ Perform a secure discard.  A secure discard is the same as a regular discard
 except that all copies of the discarded blocks that were possibly created by
 garbage collection must also be erased.  This requires support from the device.
 .TP
+.BR \-z , " \-\-zeroout"
+Zero-fill rather than discard.
+.TP
 .BR \-v , " \-\-verbose"
 Display the aligned values of
 .I offset

diff --git a/sys-utils/blkdiscard.c b/sys-utils/blkdiscard.c
index f36e504927938a526ec47d7b97eb07d8fb8a21a8..ff2cee3558b875280142ae4178affd7d5b2006ab 100644 (file)
--- a/sys-utils/blkdiscard.c
+++ b/sys-utils/blkdiscard.c
@@ -45,16 +45,37 @@
 #include "monotonic.h"
 
 #ifndef BLKDISCARD
-#define BLKDISCARD     _IO(0x12,119)
+# define BLKDISCARD    _IO(0x12,119)
 #endif
 
 #ifndef BLKSECDISCARD
-#define BLKSECDISCARD  _IO(0x12,125)
+# define BLKSECDISCARD _IO(0x12,125)
 #endif
 
-#define print_stats(path, stats) \
-       printf(_("%s: Discarded %" PRIu64 " bytes from the " \
-                "offset %" PRIu64"\n"), path, stats[1], stats[0]);
+#ifndef BLKZEROOUT
+# define BLKZEROOUT    _IO(0x12,127)
+#endif
+
+enum {
+       ACT_DISCARD = 0,        /* default */
+       ACT_ZEROOUT,
+       ACT_SECURE
+};
+
+static void print_stats(int act, char *path, uint64_t stats[])
+{
+       switch (act) {
+       case ACT_ZEROOUT:
+               printf(_("%s: Zero-filled %" PRIu64 " bytes from the offset %" PRIu64"\n"), \
+                       path, stats[1], stats[0]);
+               break;
+       case ACT_SECURE:
+       case ACT_DISCARD:
+               printf(_("%s: Discarded %" PRIu64 " bytes from the offset %" PRIu64"\n"), \
+                       path, stats[1], stats[0]);
+               break;
+       }
+}
 
 static void __attribute__((__noreturn__)) usage(FILE *out)
 {
@@ -70,6 +91,7 @@ static void __attribute__((__noreturn__)) usage(FILE *out)
                " -l, --length <num>  length of bytes to discard from the offset\n"
                " -p, --step <num>    size of the discard iterations within the offset\n"
                " -s, --secure        perform secure discard\n"
+               " -z, --zeroout       zero-fill rather than discard\n"
                " -v, --verbose       print aligned length and offset\n"),
                out);
        fputs(USAGE_SEPARATOR, out);
@@ -79,13 +101,15 @@ static void __attribute__((__noreturn__)) usage(FILE *out)
        exit(out == stderr ? EXIT_FAILURE : EXIT_SUCCESS);
 }
 
+
 int main(int argc, char **argv)
 {
        char *path;
-       int c, fd, verbose = 0, secure = 0, secsize;
+       int c, fd, verbose = 0, secsize;
        uint64_t end, blksize, step, range[2], stats[2];
        struct stat sb;
        struct timeval now, last;
+       int act = ACT_DISCARD;
 
        static const struct option longopts[] = {
            { "help",      0, 0, 'h' },
@@ -95,6 +119,7 @@ int main(int argc, char **argv)
            { "step",      1, 0, 'p' },
            { "secure",    0, 0, 's' },
            { "verbose",   0, 0, 'v' },
+           { "zeroout",   0, 0, 'z' },
            { NULL,        0, 0, 0 }
        };
 
@@ -107,7 +132,7 @@ int main(int argc, char **argv)
        range[1] = ULLONG_MAX;
        step = 0;
 
-       while ((c = getopt_long(argc, argv, "hVsvo:l:p:", longopts, NULL)) != -1) {
+       while ((c = getopt_long(argc, argv, "hVsvo:l:p:z", longopts, NULL)) != -1) {
                switch(c) {
                case 'h':
                        usage(stdout);
@@ -128,11 +153,14 @@ int main(int argc, char **argv)
                                        _("failed to parse step"));
                        break;
                case 's':
-                       secure = 1;
+                       act = ACT_SECURE;
                        break;
                case 'v':
                        verbose = 1;
                        break;
+               case 'z':
+                       act = ACT_ZEROOUT;
+                       break;
                default:
                        usage(stderr);
                        break;
@@ -189,12 +217,19 @@ int main(int argc, char **argv)
                if (range[0] + range[1] > end)
                        range[1] = end - range[0];
 
-               if (secure) {
+               switch (act) {
+               case ACT_ZEROOUT:
+                       if (ioctl(fd, BLKZEROOUT, &range))
+                                err(EXIT_FAILURE, _("%s: BLKZEROOUT ioctl failed"), path);
+                       break;
+               case ACT_SECURE:
                        if (ioctl(fd, BLKSECDISCARD, &range))
                                err(EXIT_FAILURE, _("%s: BLKSECDISCARD ioctl failed"), path);
-               } else {
+                       break;
+               case ACT_DISCARD:
                        if (ioctl(fd, BLKDISCARD, &range))
                                err(EXIT_FAILURE, _("%s: BLKDISCARD ioctl failed"), path);
+                       break;
                }
 
                stats[1] += range[1];
@@ -204,7 +239,7 @@ int main(int argc, char **argv)
                        gettime_monotonic(&now);
                        if (now.tv_sec > last.tv_sec &&
                            (now.tv_usec >= last.tv_usec || now.tv_sec > last.tv_sec + 1)) {
-                               print_stats(path, stats);
+                               print_stats(act, path, stats);
                                stats[0] += stats[1], stats[1] = 0;
                                last = now;
                        }
@@ -212,7 +247,7 @@ int main(int argc, char **argv)
        }
 
        if (verbose && stats[1])
-               print_stats(path, stats);
+               print_stats(act, path, stats);
 
        close(fd);
        return EXIT_SUCCESS;