On Fri, 19 Oct 2012 08:20:49 -0400 Jeff Layton <[email protected]> wrote:
> We want to allow unused idmap keys to eventually be purged from the > cache. Implement that by simply setting a timeout on the key whenever we > use it. We use the same default timeout as the NFS idmap cache, but add > a module parm to make it tunable. > > Signed-off-by: Jeff Layton <[email protected]> > --- > fs/cifs/cifsacl.c | 8 ++++++++ > 1 file changed, 8 insertions(+) > > diff --git a/fs/cifs/cifsacl.c b/fs/cifs/cifsacl.c > index 12d70ee..0c0a594 100644 > --- a/fs/cifs/cifsacl.c > +++ b/fs/cifs/cifsacl.c > @@ -26,6 +26,7 @@ > #include <linux/string.h> > #include <linux/keyctl.h> > #include <linux/key-type.h> > +#include <linux/moduleparam.h> > #include <keys/user-type.h> > #include "cifspdu.h" > #include "cifsglob.h" > @@ -44,6 +45,11 @@ static const struct cifs_sid sid_user = {1, 2 , {0, 0, 0, > 0, 0, 5}, {} }; > > static const struct cred *root_cred; > > +static unsigned int cifs_idmap_cache_timeout = 600; > +module_param(cifs_idmap_cache_timeout, uint, 0644); > +MODULE_PARM_DESC(cifs_idmap_cache_timeout, "Number of seconds that ID > mappings " > + "stay in cache. (default=600)"); > + > static int > cifs_idmap_key_instantiate(struct key *key, struct key_preparsed_payload > *prep) > { > @@ -214,6 +220,7 @@ id_to_sid(unsigned int cid, uint sidtype, struct cifs_sid > *ssid) > goto out_key_put; > } > cifs_copy_sid(ssid, (struct cifs_sid *)sidkey->payload.data); > + key_set_timeout(sidkey, cifs_idmap_cache_timeout); > out_key_put: > key_put(sidkey); > out_revert_creds: > @@ -272,6 +279,7 @@ sid_to_id(struct cifs_sb_info *cifs_sb, struct cifs_sid > *psid, > else > fgid = (gid_t)sidkey->payload.value; > > + key_set_timeout(sidkey, cifs_idmap_cache_timeout); > out_key_put: > key_put(sidkey); > out_revert_creds: Now that I've given this some thought, I think we might be better off removing the above patch and instead having the userspace program set the timeout on the keys. It's a pity that older versions of the program didn't do that, but no one has reported a problem with that so far... Thoughts? -- Jeff Layton <[email protected]> -- To unsubscribe from this list: send the line "unsubscribe linux-cifs" in the body of a message to [email protected] More majordomo info at http://vger.kernel.org/majordomo-info.html
