mon, doc: overriding ec profile requires --yes-i-really-mean-it

This is per https://tracker.ceph.com/issues/64333#note-17 describing
driving factors of a catastrophic cluster failure.

Signed-off-by: Radoslaw Zarzynski <[email protected]>

Author: rzarzynski

doc/rados/operations/erasure-code-profile.rst

@@ -96,7 +96,9 @@ Where:
 ``--force``
 
 :Description: Override an existing profile by the same name, and allow
-              setting a non-4K-aligned stripe_unit.
+              setting a non-4K-aligned stripe_unit. Overriding an existing
+              profile can be dangerous, and thus ``--yes-i-really-mean-it``
+              must be used as well.
 
 :Type: String
 :Required: No.

src/mon/OSDMonitor.cc

@@ -11305,6 +11305,8 @@ bool OSDMonitor::prepare_command_impl(MonOpRequestRef op,
 	  err = 0;
 	  goto reply_no_propose;
 	}
+	bool force_no_fake = false;
+	cmd_getval(cmdmap, "yes_i_really_mean_it", force_no_fake);
 	if (!force) {
 	  err = -EPERM;
 	  ss << "will not override erasure code profile " << name
@@ -11313,6 +11315,11 @@ bool OSDMonitor::prepare_command_impl(MonOpRequestRef op,
 	     << " is different from the proposed profile "
 	     << profile_map;
 	  goto reply_no_propose;
+	} else if (!force_no_fake) {
+	  err = -EPERM;
+	  ss << "overriding erasure code profile can be DANGEROUS"
+	     << "; add --yes-i-really-mean-it to do it anyway";
+	  goto reply_no_propose;
 	}
       }