sunrpc: Add a sysfs file for one-step xprt deletion

Previously, the admin would need to set the xprt state to "offline"
before attempting to remove. This patch adds a new sysfs attr that does
both these steps in a single call.

Suggested-by: Benjamin Coddington <bcodding@redhat.com>
Reviewed-by: Benjamin Coddington <bcodding@redhat.com>
Signed-off-by: Anna Schumaker <anna.schumaker@oracle.com>
Link: https://lore.kernel.org/r/20250207204225.594002-6-anna@kernel.org
Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>

diff --git a/net/sunrpc/sysfs.c b/net/sunrpc/sysfs.c
index 8fd1975f2fe8090836ae53ee34f0072308404780..09434e1143c532931bb44fa62368cc633d461435 100644 (file)
--- a/net/sunrpc/sysfs.c
+++ b/net/sunrpc/sysfs.c
@@ -286,6 +286,14 @@ static ssize_t rpc_sysfs_xprt_state_show(struct kobject *kobj,
        return ret;
 }
 
+static ssize_t rpc_sysfs_xprt_del_xprt_show(struct kobject *kobj,
+                                           struct kobj_attribute *attr,
+                                           char *buf)
+{
+       return sprintf(buf, "# delete this xprt\n");
+}
+
+
 static ssize_t rpc_sysfs_xprt_switch_info_show(struct kobject *kobj,
                                               struct kobj_attribute *attr,
                                               char *buf)
@@ -464,6 +472,40 @@ out_put:
        return count;
 }
 
+static ssize_t rpc_sysfs_xprt_del_xprt(struct kobject *kobj,
+                                      struct kobj_attribute *attr,
+                                      const char *buf, size_t count)
+{
+       struct rpc_xprt *xprt = rpc_sysfs_xprt_kobj_get_xprt(kobj);
+       struct rpc_xprt_switch *xps = rpc_sysfs_xprt_kobj_get_xprt_switch(kobj);
+
+       if (!xprt || !xps) {
+               count = 0;
+               goto out;
+       }
+
+       if (xprt->main) {
+               count = -EINVAL;
+               goto release_tasks;
+       }
+
+       if (wait_on_bit_lock(&xprt->state, XPRT_LOCKED, TASK_KILLABLE)) {
+               count = -EINTR;
+               goto out_put;
+       }
+
+       xprt_set_offline_locked(xprt, xps);
+       xprt_delete_locked(xprt, xps);
+
+release_tasks:
+       xprt_release_write(xprt, NULL);
+out_put:
+       xprt_put(xprt);
+       xprt_switch_put(xps);
+out:
+       return count;
+}
+
 int rpc_sysfs_init(void)
 {
        rpc_sunrpc_kset = kset_create_and_add("sunrpc", NULL, kernel_kobj);
@@ -559,12 +601,16 @@ static struct kobj_attribute rpc_sysfs_xprt_info = __ATTR(xprt_info,
 static struct kobj_attribute rpc_sysfs_xprt_change_state = __ATTR(xprt_state,
        0644, rpc_sysfs_xprt_state_show, rpc_sysfs_xprt_state_change);
 
+static struct kobj_attribute rpc_sysfs_xprt_del = __ATTR(del_xprt,
+       0644, rpc_sysfs_xprt_del_xprt_show, rpc_sysfs_xprt_del_xprt);
+
 static struct attribute *rpc_sysfs_xprt_attrs[] = {
        &rpc_sysfs_xprt_dstaddr.attr,
        &rpc_sysfs_xprt_srcaddr.attr,
        &rpc_sysfs_xprt_xprtsec.attr,
        &rpc_sysfs_xprt_info.attr,
        &rpc_sysfs_xprt_change_state.attr,
+       &rpc_sysfs_xprt_del.attr,
        NULL,
 };
 ATTRIBUTE_GROUPS(rpc_sysfs_xprt);