diff options
Diffstat (limited to 'net/sunrpc/auth_gss')
| -rw-r--r-- | net/sunrpc/auth_gss/auth_gss.c | 53 |
1 files changed, 36 insertions, 17 deletions
diff --git a/net/sunrpc/auth_gss/auth_gss.c b/net/sunrpc/auth_gss/auth_gss.c index 8653a92144ae..15da6f82db36 100644 --- a/net/sunrpc/auth_gss/auth_gss.c +++ b/net/sunrpc/auth_gss/auth_gss.c @@ -78,8 +78,6 @@ static const struct rpc_credops gss_credops; /* dump the buffer in `emacs-hexl' style */ #define isprint(c) ((c > 0x1f) && (c < 0x7f)) -static DEFINE_RWLOCK(gss_ctx_lock); - struct gss_auth { struct rpc_auth rpc_auth; struct gss_api_mech *mech; @@ -88,7 +86,7 @@ struct gss_auth { struct dentry *dentry; }; -static void gss_destroy_ctx(struct gss_cl_ctx *); +static void gss_free_ctx(struct gss_cl_ctx *); static struct rpc_pipe_ops gss_upcall_ops; static inline struct gss_cl_ctx * @@ -102,20 +100,24 @@ static inline void gss_put_ctx(struct gss_cl_ctx *ctx) { if (atomic_dec_and_test(&ctx->count)) - gss_destroy_ctx(ctx); + gss_free_ctx(ctx); } +/* gss_cred_set_ctx: + * called by gss_upcall_callback and gss_create_upcall in order + * to set the gss context. The actual exchange of an old context + * and a new one is protected by the inode->i_lock. + */ static void gss_cred_set_ctx(struct rpc_cred *cred, struct gss_cl_ctx *ctx) { struct gss_cred *gss_cred = container_of(cred, struct gss_cred, gc_base); struct gss_cl_ctx *old; - write_lock(&gss_ctx_lock); + old = gss_cred->gc_ctx; - gss_cred->gc_ctx = ctx; + rcu_assign_pointer(gss_cred->gc_ctx, ctx); set_bit(RPCAUTH_CRED_UPTODATE, &cred->cr_flags); clear_bit(RPCAUTH_CRED_NEW, &cred->cr_flags); - write_unlock(&gss_ctx_lock); if (old) gss_put_ctx(old); } @@ -126,10 +128,10 @@ gss_cred_is_uptodate_ctx(struct rpc_cred *cred) struct gss_cred *gss_cred = container_of(cred, struct gss_cred, gc_base); int res = 0; - read_lock(&gss_ctx_lock); + rcu_read_lock(); if (test_bit(RPCAUTH_CRED_UPTODATE, &cred->cr_flags) && gss_cred->gc_ctx) res = 1; - read_unlock(&gss_ctx_lock); + rcu_read_unlock(); return res; } @@ -168,10 +170,10 @@ gss_cred_get_ctx(struct rpc_cred *cred) struct gss_cred *gss_cred = container_of(cred, struct gss_cred, gc_base); struct gss_cl_ctx *ctx = NULL; - read_lock(&gss_ctx_lock); + rcu_read_lock(); if (gss_cred->gc_ctx) ctx = gss_get_ctx(gss_cred->gc_ctx); - read_unlock(&gss_ctx_lock); + rcu_read_unlock(); return ctx; } @@ -333,11 +335,11 @@ gss_upcall_callback(struct rpc_task *task) struct gss_upcall_msg *gss_msg = gss_cred->gc_upcall; struct inode *inode = gss_msg->auth->dentry->d_inode; + spin_lock(&inode->i_lock); if (gss_msg->ctx) gss_cred_set_ctx(task->tk_msg.rpc_cred, gss_get_ctx(gss_msg->ctx)); else task->tk_status = gss_msg->msg.errno; - spin_lock(&inode->i_lock); gss_cred->gc_upcall = NULL; rpc_wake_up_status(&gss_msg->rpc_waitqueue, gss_msg->msg.errno); spin_unlock(&inode->i_lock); @@ -440,7 +442,6 @@ gss_create_upcall(struct gss_auth *gss_auth, struct gss_cred *gss_cred) prepare_to_wait(&gss_msg->waitqueue, &wait, TASK_INTERRUPTIBLE); spin_lock(&inode->i_lock); if (gss_msg->ctx != NULL || gss_msg->msg.errno < 0) { - spin_unlock(&inode->i_lock); break; } spin_unlock(&inode->i_lock); @@ -454,6 +455,7 @@ gss_create_upcall(struct gss_auth *gss_auth, struct gss_cred *gss_cred) gss_cred_set_ctx(cred, gss_get_ctx(gss_msg->ctx)); else err = gss_msg->msg.errno; + spin_unlock(&inode->i_lock); out_intr: finish_wait(&gss_msg->waitqueue, &wait); gss_release_msg(gss_msg); @@ -681,9 +683,9 @@ gss_destroy(struct rpc_auth *auth) * to create a new cred or context, so they check that things have been * allocated before freeing them. */ static void -gss_destroy_ctx(struct gss_cl_ctx *ctx) +gss_do_free_ctx(struct gss_cl_ctx *ctx) { - dprintk("RPC: gss_destroy_ctx\n"); + dprintk("RPC: gss_free_ctx\n"); if (ctx->gc_gss_ctx) gss_delete_sec_context(&ctx->gc_gss_ctx); @@ -693,11 +695,22 @@ gss_destroy_ctx(struct gss_cl_ctx *ctx) } static void +gss_free_ctx_callback(struct rcu_head *head) +{ + struct gss_cl_ctx *ctx = container_of(head, struct gss_cl_ctx, gc_rcu); + gss_do_free_ctx(ctx); +} + +static void +gss_free_ctx(struct gss_cl_ctx *ctx) +{ + call_rcu(&ctx->gc_rcu, gss_free_ctx_callback); +} + +static void gss_free_cred(struct gss_cred *gss_cred) { dprintk("RPC: gss_free_cred %p\n", gss_cred); - if (gss_cred->gc_ctx) - gss_put_ctx(gss_cred->gc_ctx); kfree(gss_cred); } @@ -711,7 +724,13 @@ gss_free_cred_callback(struct rcu_head *head) static void gss_destroy_cred(struct rpc_cred *cred) { + struct gss_cred *gss_cred = container_of(cred, struct gss_cred, gc_base); + struct gss_cl_ctx *ctx = gss_cred->gc_ctx; + + rcu_assign_pointer(gss_cred->gc_ctx, NULL); call_rcu(&cred->cr_rcu, gss_free_cred_callback); + if (ctx) + gss_put_ctx(ctx); } /* |