3 files changed, 186 insertions, 2 deletions

diff --git a/fs/nfsd/nfs4recover.c b/fs/nfsd/nfs4recover.c
index 841a305d7948..2dc9851a1d37 100644
--- a/fs/nfsd/nfs4recover.c
+++ b/fs/nfsd/nfs4recover.c
@@ -39,6 +39,9 @@
 #include <linux/nfs4.h>
 #include <linux/nfsd/state.h>
 #include <linux/nfsd/xdr4.h>
+#include <linux/param.h>
+#include <linux/file.h>
+#include <linux/namei.h>
 #include <asm/uaccess.h>
 #include <asm/scatterlist.h>
 #include <linux/crypto.h>
@@ -46,6 +49,27 @@
 
 #define NFSDDBG_FACILITY                NFSDDBG_PROC
 
+/* Globals */
+char recovery_dirname[PATH_MAX] = "/var/lib/nfs/v4recovery";
+static struct nameidata rec_dir;
+static int rec_dir_init = 0;
+
+static void
+nfs4_save_user(uid_t *saveuid, gid_t *savegid)
+{
+        *saveuid = current->fsuid;
+        *savegid = current->fsgid;
+        current->fsuid = 0;
+        current->fsgid = 0;
+}
+
+static void
+nfs4_reset_user(uid_t saveuid, gid_t savegid)
+{
+        current->fsuid = saveuid;
+        current->fsgid = savegid;
+}
+
 static void
 md5_to_hex(char *out, char *md5)
 {
@@ -95,3 +119,145 @@ out:
                 crypto_free_tfm(tfm);
         return status;
 }
+
+typedef int (recdir_func)(struct dentry *, struct dentry *);
+
+struct dentry_list {
+        struct dentry *dentry;
+        struct list_head list;
+};
+
+struct dentry_list_arg {
+        struct list_head dentries;
+        struct dentry *parent;
+};
+
+static int
+nfsd4_build_dentrylist(void *arg, const char *name, int namlen,
+                loff_t offset, ino_t ino, unsigned int d_type)
+{
+        struct dentry_list_arg *dla = arg;
+        struct list_head *dentries = &dla->dentries;
+        struct dentry *parent = dla->parent;
+        struct dentry *dentry;
+        struct dentry_list *child;
+
+        if (name && isdotent(name, namlen))
+                return nfs_ok;
+        dentry = lookup_one_len(name, parent, namlen);
+        if (IS_ERR(dentry))
+                return PTR_ERR(dentry);
+        child = kmalloc(sizeof(*child), GFP_KERNEL);
+        if (child == NULL)
+                return -ENOMEM;
+        child->dentry = dentry;
+        list_add(&child->list, dentries);
+        return 0;
+}
+
+static int
+nfsd4_list_rec_dir(struct dentry *dir, recdir_func *f)
+{
+        struct file *filp;
+        struct dentry_list_arg dla = {
+                .parent = dir,
+        };
+        struct list_head *dentries = &dla.dentries;
+        struct dentry_list *child;
+        uid_t uid;
+        gid_t gid;
+        int status;
+
+        if (!rec_dir_init)
+                return 0;
+
+        nfs4_save_user(&uid, &gid);
+
+        filp = dentry_open(dget(dir), mntget(rec_dir.mnt),
+                        O_RDWR);
+        status = PTR_ERR(filp);
+        if (IS_ERR(filp))
+                goto out;
+        INIT_LIST_HEAD(dentries);
+        status = vfs_readdir(filp, nfsd4_build_dentrylist, &dla);
+        fput(filp);
+        while (!list_empty(dentries)) {
+                child = list_entry(dentries->next, struct dentry_list, list);
+                status = f(dir, child->dentry);
+                if (status)
+                        goto out;
+                list_del(&child->list);
+                dput(child->dentry);
+                kfree(child);
+        }
+out:
+        while (!list_empty(dentries)) {
+                child = list_entry(dentries->next, struct dentry_list, list);
+                list_del(&child->list);
+                dput(child->dentry);
+                kfree(child);
+        }
+        nfs4_reset_user(uid, gid);
+        return status;
+}
+
+static int
+load_recdir(struct dentry *parent, struct dentry *child)
+{
+        if (child->d_name.len != HEXDIR_LEN - 1) {
+                printk("nfsd4: illegal name %s in recovery directory\n",
+                                child->d_name.name);
+                /* Keep trying; maybe the others are OK: */
+                return nfs_ok;
+        }
+        nfs4_client_to_reclaim(child->d_name.name);
+        return nfs_ok;
+}
+
+int
+nfsd4_recdir_load(void) {
+        int status;
+
+        status = nfsd4_list_rec_dir(rec_dir.dentry, load_recdir);
+        if (status)
+                printk("nfsd4: failed loading clients from recovery"
+                        " directory %s\n", rec_dir.dentry->d_name.name);
+        return status;
+}
+
+/*
+ * Hold reference to the recovery directory.
+ */
+
+void
+nfsd4_init_recdir(char *rec_dirname)
+{
+        uid_t                   uid = 0;
+        gid_t                   gid = 0;
+        int                     status;
+
+        printk("NFSD: Using %s as the NFSv4 state recovery directory\n",
+                        rec_dirname);
+
+        BUG_ON(rec_dir_init);
+
+        nfs4_save_user(&uid, &gid);
+
+        status = path_lookup(rec_dirname, LOOKUP_FOLLOW, &rec_dir);
+        if (status == -ENOENT)
+                printk("NFSD: recovery directory %s doesn't exist\n",
+                                rec_dirname);
+
+        if (!status)
+                rec_dir_init = 1;
+        nfs4_reset_user(uid, gid);
+}
+
+void
+nfsd4_shutdown_recdir(void)
+{
+        if (!rec_dir_init)
+                return;
+        rec_dir_init = 0;
+        path_release(&rec_dir);
+}
diff --git a/fs/nfsd/nfs4state.c b/fs/nfsd/nfs4state.c
index 0b47a97e953d..6b9d23c39afe 100644
--- a/fs/nfsd/nfs4state.c
+++ b/fs/nfsd/nfs4state.c
@@ -71,6 +71,7 @@ static stateid_t onestateid;              /* bits all 1 */
 static struct nfs4_stateid * find_stateid(stateid_t *stid, int flags);
 static struct nfs4_delegation * find_delegation_stateid(struct inode *ino, stateid_t *stid);
 static void release_stateid_lockowners(struct nfs4_stateid *open_stp);
+extern char recovery_dirname[];
 
 /* Locking:
  *
@@ -3091,8 +3092,8 @@ alloc_reclaim(void)
 /*
  * failure => all reset bets are off, nfserr_no_grace...
  */
-static int
-nfs4_client_to_reclaim(char *name)
+int
+nfs4_client_to_reclaim(const char *name)
 {
         unsigned int strhashval;
         struct nfs4_client_reclaim *crp = NULL;
@@ -3202,6 +3203,17 @@ nfs4_state_init(void)
         reclaim_str_hashtbl_size = 0;
 }
 
+static void
+nfsd4_load_reboot_recovery_data(void)
+{
+        int status;
+
+        nfsd4_init_recdir(recovery_dirname);
+        status = nfsd4_recdir_load();
+        if (status)
+                printk("NFSD: Failure reading reboot recovery data\n");
+}
+
 /* initialization to perform when the nfsd service is started: */
 
 static void
@@ -3228,6 +3240,7 @@ nfs4_state_start(void)
         status = nfsd4_init_slabs();
         if (status)
                 return status;
+        nfsd4_load_reboot_recovery_data();
         __nfs4_state_start();
         nfs4_init = 1;
         return 0;
@@ -3286,6 +3299,7 @@ __nfs4_state_shutdown(void)
         cancel_delayed_work(&laundromat_work);
         flush_workqueue(laundry_wq);
         destroy_workqueue(laundry_wq);
+        nfsd4_shutdown_recdir();
         nfs4_init = 0;
 }
 
diff --git a/include/linux/nfsd/state.h b/include/linux/nfsd/state.h
index 83d29ec03a58..19481ab122df 100644
--- a/include/linux/nfsd/state.h
+++ b/include/linux/nfsd/state.h
@@ -278,6 +278,10 @@ extern void nfsd4_probe_callback(struct nfs4_client *clp);
 extern void nfsd4_cb_recall(struct nfs4_delegation *dp);
 extern void nfs4_put_delegation(struct nfs4_delegation *dp);
 extern int nfs4_make_rec_clidname(char *clidname, struct xdr_netobj *clname);
+extern void nfsd4_init_recdir(char *recdir_name);
+extern int nfsd4_recdir_load(void);
+extern void nfsd4_shutdown_recdir(void);
+extern int nfs4_client_to_reclaim(const char *name);
 
 static inline void
 nfs4_put_stateowner(struct nfs4_stateowner *so)