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authorNiklas Cassel <cassel@kernel.org>2026-09-16 15:00:32 +0200
committerNiklas Cassel <cassel@kernel.org>2026-09-16 16:18:00 +0200
commit8d836581f9b1f57ceaa2b47654754ef1260b410b (patch)
tree1dbd4d0dfb99c2e238356cbe947e5b0be3e3a571 /fs/nfs/cache_lib.c
downloadlinux-stable-8d836581f9b1f57ceaa2b47654754ef1260b410b.tar.gz
linux-stable-8d836581f9b1f57ceaa2b47654754ef1260b410b.zip
ata: libata-scsi: fix ata_dsm_trim_pages() kernel-docgrafted
make htmldocs fails with: Documentation/driver-api/libata:604: ./drivers/ata/libata-scsi.c:2301: ERROR: Unexpected indentation. [docutils] The Return: section of ata_dsm_trim_pages() ends its first sentence with a colon and continues with an indented bullet list. reStructuredText requires a blank line before an indented block, so docutils chokes on the list. Simply adding the missing blank line does not work either: Return: is a kernel-doc "special section", which is terminated by the first blank line, so the bullet list would end up in the Description section, detached from the sentence introducing it. Spell the two bounds out as prose instead, so that the Return: section stays self-contained. Documentation-only change. Fixes: e64e6b5dc867 ("ata: libata-scsi: scale DSM TRIM payload by MAX PAGES PER DSM COMMAND") Reported-by: Thomas Huth <thuth@redhat.com> Closes: https://lore.kernel.org/linux-ide/b0a0b8e8-cc4f-4c7b-8bc5-fee0712d405a@redhat.com/ Reviewed-by: Damien Le Moal <dlemoal@kernel.org> Reviewed-by: Thomas Huth <thuth@redhat.com> Link: https://lore.kernel.org/r/20260916130031.29990-2-cassel@kernel.org Signed-off-by: Niklas Cassel <cassel@kernel.org>
Diffstat (limited to 'fs/nfs/cache_lib.c')
-rw-r--r--fs/nfs/cache_lib.c158
1 files changed, 158 insertions, 0 deletions
diff --git a/fs/nfs/cache_lib.c b/fs/nfs/cache_lib.c
new file mode 100644
index 000000000..9738a1ae9
--- /dev/null
+++ b/fs/nfs/cache_lib.c
@@ -0,0 +1,158 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * linux/fs/nfs/cache_lib.c
+ *
+ * Helper routines for the NFS client caches
+ *
+ * Copyright (c) 2009 Trond Myklebust <Trond.Myklebust@netapp.com>
+ */
+#include <linux/kmod.h>
+#include <linux/module.h>
+#include <linux/moduleparam.h>
+#include <linux/mount.h>
+#include <linux/namei.h>
+#include <linux/slab.h>
+#include <linux/sunrpc/cache.h>
+#include <linux/sunrpc/rpc_pipe_fs.h>
+#include <net/net_namespace.h>
+
+#include "cache_lib.h"
+
+#define NFS_CACHE_UPCALL_PATHLEN 256
+#define NFS_CACHE_UPCALL_TIMEOUT 15
+
+static char nfs_cache_getent_prog[NFS_CACHE_UPCALL_PATHLEN] =
+ "/sbin/nfs_cache_getent";
+static unsigned long nfs_cache_getent_timeout = NFS_CACHE_UPCALL_TIMEOUT;
+
+module_param_string(cache_getent, nfs_cache_getent_prog,
+ sizeof(nfs_cache_getent_prog), 0600);
+MODULE_PARM_DESC(cache_getent, "Path to the client cache upcall program");
+module_param_named(cache_getent_timeout, nfs_cache_getent_timeout, ulong, 0600);
+MODULE_PARM_DESC(cache_getent_timeout, "Timeout (in seconds) after which "
+ "the cache upcall is assumed to have failed");
+
+int nfs_cache_upcall(struct cache_detail *cd, char *entry_name)
+{
+ static char *envp[] = { "HOME=/",
+ "TERM=linux",
+ "PATH=/sbin:/usr/sbin:/bin:/usr/bin",
+ NULL
+ };
+ char *argv[] = {
+ nfs_cache_getent_prog,
+ cd->name,
+ entry_name,
+ NULL
+ };
+ int ret = -EACCES;
+
+ if (nfs_cache_getent_prog[0] == '\0')
+ goto out;
+ ret = call_usermodehelper(argv[0], argv, envp, UMH_WAIT_EXEC);
+ /*
+ * Disable the upcall mechanism if we're getting an ENOENT or
+ * EACCES error. The admin can re-enable it on the fly by using
+ * sysfs to set the 'cache_getent' parameter once the problem
+ * has been fixed.
+ */
+ if (ret == -ENOENT || ret == -EACCES)
+ nfs_cache_getent_prog[0] = '\0';
+out:
+ return ret > 0 ? 0 : ret;
+}
+
+/*
+ * Deferred request handling
+ */
+void nfs_cache_defer_req_put(struct nfs_cache_defer_req *dreq)
+{
+ if (refcount_dec_and_test(&dreq->count))
+ kfree(dreq);
+}
+
+static void nfs_dns_cache_revisit(struct cache_deferred_req *d, int toomany)
+{
+ struct nfs_cache_defer_req *dreq;
+
+ dreq = container_of(d, struct nfs_cache_defer_req, deferred_req);
+
+ complete(&dreq->completion);
+ nfs_cache_defer_req_put(dreq);
+}
+
+static struct cache_deferred_req *nfs_dns_cache_defer(struct cache_req *req)
+{
+ struct nfs_cache_defer_req *dreq;
+
+ dreq = container_of(req, struct nfs_cache_defer_req, req);
+ dreq->deferred_req.revisit = nfs_dns_cache_revisit;
+ refcount_inc(&dreq->count);
+
+ return &dreq->deferred_req;
+}
+
+struct nfs_cache_defer_req *nfs_cache_defer_req_alloc(void)
+{
+ struct nfs_cache_defer_req *dreq;
+
+ dreq = kzalloc_obj(*dreq);
+ if (dreq) {
+ init_completion(&dreq->completion);
+ refcount_set(&dreq->count, 1);
+ dreq->req.defer = nfs_dns_cache_defer;
+ }
+ return dreq;
+}
+
+int nfs_cache_wait_for_upcall(struct nfs_cache_defer_req *dreq)
+{
+ if (wait_for_completion_timeout(&dreq->completion,
+ nfs_cache_getent_timeout * HZ) == 0)
+ return -ETIMEDOUT;
+ return 0;
+}
+
+int nfs_cache_register_sb(struct super_block *sb, struct cache_detail *cd)
+{
+ int ret;
+ struct dentry *dir;
+
+ dir = rpc_d_lookup_sb(sb, "cache");
+ ret = sunrpc_cache_register_pipefs(dir, cd->name, 0600, cd);
+ dput(dir);
+ return ret;
+}
+
+int nfs_cache_register_net(struct net *net, struct cache_detail *cd)
+{
+ struct super_block *pipefs_sb;
+ int ret = 0;
+
+ sunrpc_init_cache_detail(cd);
+ pipefs_sb = rpc_get_sb_net(net);
+ if (pipefs_sb) {
+ ret = nfs_cache_register_sb(pipefs_sb, cd);
+ rpc_put_sb_net(net);
+ if (ret)
+ sunrpc_destroy_cache_detail(cd);
+ }
+ return ret;
+}
+
+void nfs_cache_unregister_sb(struct super_block *sb, struct cache_detail *cd)
+{
+ sunrpc_cache_unregister_pipefs(cd);
+}
+
+void nfs_cache_unregister_net(struct net *net, struct cache_detail *cd)
+{
+ struct super_block *pipefs_sb;
+
+ pipefs_sb = rpc_get_sb_net(net);
+ if (pipefs_sb) {
+ nfs_cache_unregister_sb(pipefs_sb, cd);
+ rpc_put_sb_net(net);
+ }
+ sunrpc_destroy_cache_detail(cd);
+}