From: Sachin Bhamare <sbhamare@xxxxxxxxxxx>
The pnfs-objects protocol mandates that we autologin into devices not
present in the system, according to information specified in the
get_device_info returned from the server.
The Protocol specifies two login hints.
1. An IP address:port combination
2. A string URI which is constructed as a URL with a protocol prefix
followed by :// and a string as address. For each protocol prefix
the string-address format might be different.
We only support the second option. The first option is just redundant
to the second one.
NOTE: The Kernel part of autologin does not parse the URI string. It
just channels it to a user-mode script. So any new login protocols should
only update the user-mode script which is a part of the nfs-utils package,
but the Kernel need not change.
We implement the autologin by using the call_usermodehelper() API.
(Thanks to Steve Dickson <steved@xxxxxxxxxx> for pointing it out)
So there is no running daemon needed, and or special setup.
All is needed is that "/sbin/osd_login" script exists.
TODO:
"osd_login" is an hard coded name. If not present we will rate_limit
print to dmsg and keep failing. In such cases we should stop trying
and provide sysfs interface for re-enabling autologin. For example,
we could ZERO out the script name and let user-mode set a new script
name.
[Q] Where in sysfs should a layout-driver put its things?
Signed-off-by: Sachin Bhamare <sbhamare@xxxxxxxxxxx>
Signed-off-by: Boaz Harrosh <bharrosh@xxxxxxxxxxx>
---
fs/nfs/objlayout/objio_osd.c | 9 +++
fs/nfs/objlayout/objlayout.c | 120 ++++++++++++++++++++++++++++++++++++++++++
fs/nfs/objlayout/objlayout.h | 2 +
3 files changed, 131 insertions(+), 0 deletions(-)
diff --git a/fs/nfs/objlayout/objio_osd.c b/fs/nfs/objlayout/objio_osd.c
index 37a9269..5b2ac9e 100644
--- a/fs/nfs/objlayout/objio_osd.c
+++ b/fs/nfs/objlayout/objio_osd.c
@@ -137,6 +137,7 @@ static int objio_devices_lookup(struct pnfs_layout_hdr *pnfslay,
struct objio_dev_ent *ode;
struct osd_dev *od;
struct osd_dev_info odi;
+ bool retry_flag = true;
int err;
ode = _dev_list_find(NFS_SERVER(pnfslay->plh_inode), d_id);
@@ -171,10 +172,18 @@ static int objio_devices_lookup(struct pnfs_layout_hdr *pnfslay,
goto out;
}
+retry_lookup:
od = osduld_info_lookup(&odi);
if (unlikely(IS_ERR(od))) {
err = PTR_ERR(od);
dprintk("%s: osduld_info_lookup => %d\n", __func__, err);
+ if (err == -ENODEV && retry_flag) {
+ err = objlayout_autologin(deviceaddr);
+ if (likely(!err)) {
+ retry_flag = false;
+ goto retry_lookup;
+ }
+ }
goto out;
}
diff --git a/fs/nfs/objlayout/objlayout.c b/fs/nfs/objlayout/objlayout.c
index 71047c9..d953948 100644
--- a/fs/nfs/objlayout/objlayout.c
+++ b/fs/nfs/objlayout/objlayout.c
@@ -37,6 +37,8 @@
* SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
*/
+#include <linux/kmod.h>
+#include <linux/ratelimit.h>
#include <scsi/osd_initiator.h>
#include "objlayout.h"
@@ -649,3 +651,121 @@ void objlayout_put_deviceinfo(struct pnfs_osd_deviceaddr *deviceaddr)
__free_page(odi->page);
kfree(odi);
}
+
+static const char osd_login_prog[] = "/sbin/osd_login";
+
+enum {
+ OBJLAYOUT_MAX_URI_LEN = 256, OBJLAYOUT_MAX_OSDNAME_LEN = 64,
+ OBJLAYOUT_MAX_SYSID_HEX_LEN = OSD_SYSTEMID_LEN * 2 + 1,
+};
+
+struct __auto_login {
+ char uri[OBJLAYOUT_MAX_URI_LEN];
+ char osdname[OBJLAYOUT_MAX_OSDNAME_LEN];
+ char systemid_hex[OBJLAYOUT_MAX_SYSID_HEX_LEN];
+};
+
+static int __objlayout_upcall(struct __auto_login *login)
+{
+ static char *envp[] = { "HOME=/root",
+ "TERM=linux",
+ "PATH=/sbin:/usr/sbin:/bin:/usr/bin",
+ NULL
+ };
+ char *argv[8];
+ int ret;
+
+ dprintk("%s uri: %s\n", __func__, login->uri);
+ dprintk("%s osdname %s\n", __func__, login->osdname);
+ dprintk("%s systemid_hex %s\n", __func__, login->systemid_hex);
+
+ argv[0] = (char *)osd_login_prog;
+ argv[1] = "-u";
+ argv[2] = login->uri;
+ argv[3] = "-o";
+ argv[4] = login->osdname;
+ argv[5] = "-s";
+ argv[6] = login->systemid_hex;
+ argv[7] = NULL;
+
+ ret = call_usermodehelper(argv[0], argv, envp, UMH_WAIT_PROC);
+ /*
+ * TODO: 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 parameter once the problem has been fixed.
+ */
+ if (ret == -ENOENT || ret == -EACCES)
+ pr_warn_ratelimited("PNFS-OBJ:: %s: %s "
+ "was not found please install new nfs-utils pkg!\n",
+ __func__, osd_login_prog);
+ dprintk("%s %s return value: %d\n", __func__, osd_login_prog, ret);
+
+ return ret;
+}
+
+/* Assume dest is all zeros */
+static void __copy_nfsS_and_zero_terminate(struct nfs4_string s,
+ char *dest, int max_len,
+ const char *var_name)
+{
+ if (!s.len)
+ return;
+
+ if (s.len >= max_len) {
+ pr_warn_ratelimited(
+ "objlayout_autologin: %s: s.len(%d) >= max_len(%d)",
+ var_name, s.len, max_len);
+ s.len = max_len - 1; /* space for null terminator */
+ }
+
+ memcpy(dest, s.data, s.len);
+}
+
+/* Assume sysid is all zeros */
+static void _sysid_2_hex(struct nfs4_string s,
+ char sysid[OBJLAYOUT_MAX_SYSID_HEX_LEN])
+{
+ int i;
+ char *cur;
+
+ if (!s.len)
+ return;
+
+ if (s.len != OSD_SYSTEMID_LEN) {
+ pr_warn_ratelimited(
+ "objlayout_autologin: systemid_len(%d) != OSD_SYSTEMID_LEN",
+ s.len);
+ if (s.len > OSD_SYSTEMID_LEN)
+ s.len = OSD_SYSTEMID_LEN;
+ }
+
+ cur = sysid;
+ for (i = 0; i < s.len; i++)
+ cur = hex_byte_pack(cur, s.data[i]);
+}
+
+int objlayout_autologin(struct pnfs_osd_deviceaddr *deviceaddr)
+{
+ int rc;
+ struct __auto_login login;
+
+ if (!deviceaddr->oda_targetaddr.ota_netaddr.r_addr.len)
+ return -ENODEV;
+
+ memset(&login, 0, sizeof(login));
+ __copy_nfsS_and_zero_terminate(
+ deviceaddr->oda_targetaddr.ota_netaddr.r_addr,
+ login.uri, sizeof(login.uri), "URI");
+
+ __copy_nfsS_and_zero_terminate(
+ deviceaddr->oda_osdname,
+ login.osdname, sizeof(login.osdname), "OSDNAME");
+
+ _sysid_2_hex(deviceaddr->oda_systemid, login.systemid_hex);
+
+ rc = __objlayout_upcall(&login);
+ if (rc > 0) /* script returns positive values */
+ rc = -ENODEV;
+
+ return rc;
+}
diff --git a/fs/nfs/objlayout/objlayout.h b/fs/nfs/objlayout/objlayout.h
index 8ec3472..880ba08 100644
--- a/fs/nfs/objlayout/objlayout.h
+++ b/fs/nfs/objlayout/objlayout.h
@@ -184,4 +184,6 @@ extern void objlayout_encode_layoutreturn(
struct xdr_stream *,
const struct nfs4_layoutreturn_args *);
+extern int objlayout_autologin(struct pnfs_osd_deviceaddr *deviceaddr);
+
#endif /* _OBJLAYOUT_H */
--
1.7.6.2
--
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