blkzone: add report capacity command

Add a command that answers the the question:
"How much data can I store on this device/in this range of zones?"

Implement this by summing up zone capacities over the given range.

Signed-off-by: Hans Holmberg <hans.holmberg@wdc.com>

diff --git a/sys-utils/blkzone.8 b/sys-utils/blkzone.8
index 043bc96e23ac2a69289b3b6005e41487a98b59ea..958677e1bffa4ac36605cb825d95a8ccb1162df4 100644 (file)
--- a/sys-utils/blkzone.8
+++ b/sys-utils/blkzone.8
@@ -52,6 +52,13 @@ ro:Read only
 x?:Reserved conditions (should not be reported)
 .TE
 
+.SS capacity
+The command \fBblkzone capacity\fP is used to report device capacity information.
+.PP
+By default, the command will report the sum, in number of sectors, of all
+zone capacities on the device. Options may be used to modify this behavior,
+changing the starting zone or the size of the report, as explained below.
+
 .SS reset
 The command \fBblkzone reset\fP is used to reset one or more zones. Unlike
 .BR sg_reset_wp (8),

diff --git a/sys-utils/blkzone.c b/sys-utils/blkzone.c
index 67eaf1a02430d826879ccc25f39374e47d494e72..c416e0711fc39d5e62d5da791897f1f7625167d2 100644 (file)
--- a/sys-utils/blkzone.c
+++ b/sys-utils/blkzone.c
@@ -91,6 +91,10 @@ static const struct blkzone_command commands[] = {
                .name = "report",
                .handler = blkzone_report,
                .help = N_("Report zone information about the given device")
+       },{
+               .name = "capacity",
+               .handler = blkzone_report,
+               .help = N_("Report sum of zone capacities for the given device")
        },{
                .name = "reset",
                .handler = blkzone_action,
@@ -224,6 +228,8 @@ static const char *condition_str[] = {
 
 static int blkzone_report(struct blkzone_control *ctl)
 {
+       bool only_capacity_sum = !strcmp(ctl->command->name, "capacity");
+       uint64_t capacity_sum = 0;
        struct blk_zone_report *zi;
        unsigned long zonesize;
        uint32_t i, nr_zones;
@@ -290,21 +296,27 @@ static int blkzone_report(struct blkzone_control *ctl)
                        else
                                cap = entry->len;
 
-                       printf(_("  start: 0x%09"PRIx64", len 0x%06"PRIx64
-                               ", cap 0x%06"PRIx64", wptr 0x%06"PRIx64
-                               " reset:%u non-seq:%u, zcond:%2u(%s) [type: %u(%s)]\n"),
-                               start, len, cap, (type == 0x1) ? 0 : wp - start,
-                               entry->reset, entry->non_seq,
-                               cond, condition_str[cond & (ARRAY_SIZE(condition_str) - 1)],
-                               type, type_text[type]);
+                       if (only_capacity_sum) {
+                               capacity_sum += cap;
+                       } else {
+                               printf(_("  start: 0x%09"PRIx64", len 0x%06"PRIx64
+                                       ", cap 0x%06"PRIx64", wptr 0x%06"PRIx64
+                                       " reset:%u non-seq:%u, zcond:%2u(%s) [type: %u(%s)]\n"),
+                                       start, len, cap, (type == 0x1) ? 0 : wp - start,
+                                       entry->reset, entry->non_seq,
+                                       cond, condition_str[cond & (ARRAY_SIZE(condition_str) - 1)],
+                                       type, type_text[type]);
+                       }
 
                        nr_zones--;
                        ctl->offset = start + len;
-
                }
 
        }
 
+       if (only_capacity_sum)
+               printf(_("0x%09"PRIx64"\n"), capacity_sum);
+
        free(zi);
        close(fd);