IB/uverbs: Convert 'bool exclusive' into an enum

This is more readable, and future patches will need a 3rd lookup type.

Signed-off-by: Jason Gunthorpe <jgg@mellanox.com>

diff --git a/drivers/infiniband/core/rdma_core.c b/drivers/infiniband/core/rdma_core.c
index aa1d16d..435dbe8 100644 (file)
--- a/drivers/infiniband/core/rdma_core.c
+++ b/drivers/infiniband/core/rdma_core.c
@@ -108,7 +108,8 @@ void uverbs_uobject_put(struct ib_uobject *uobject)
        kref_put(&uobject->ref, uverbs_uobject_free);
 }
 
-static int uverbs_try_lock_object(struct ib_uobject *uobj, bool exclusive)
+static int uverbs_try_lock_object(struct ib_uobject *uobj,
+                                 enum rdma_lookup_mode mode)
 {
        /*
         * When a shared access is required, we use a positive counter. Each
@@ -121,21 +122,29 @@ static int uverbs_try_lock_object(struct ib_uobject *uobj, bool exclusive)
         * concurrently, setting the counter to zero is enough for releasing
         * this lock.
         */
-       if (!exclusive)
+       switch (mode) {
+       case UVERBS_LOOKUP_READ:
                return __atomic_add_unless(&uobj->usecnt, 1, -1) == -1 ?
                        -EBUSY : 0;
-
-       /* lock is either WRITE or DESTROY - should be exclusive */
-       return atomic_cmpxchg(&uobj->usecnt, 0, -1) == 0 ? 0 : -EBUSY;
+       case UVERBS_LOOKUP_WRITE:
+               /* lock is either WRITE or DESTROY - should be exclusive */
+               return atomic_cmpxchg(&uobj->usecnt, 0, -1) == 0 ? 0 : -EBUSY;
+       }
+       return 0;
 }
 
-static void assert_uverbs_usecnt(struct ib_uobject *uobj, bool exclusive)
+static void assert_uverbs_usecnt(struct ib_uobject *uobj,
+                                enum rdma_lookup_mode mode)
 {
 #ifdef CONFIG_LOCKDEP
-       if (exclusive)
-               WARN_ON(atomic_read(&uobj->usecnt) != -1);
-       else
+       switch (mode) {
+       case UVERBS_LOOKUP_READ:
                WARN_ON(atomic_read(&uobj->usecnt) <= 0);
+               break;
+       case UVERBS_LOOKUP_WRITE:
+               WARN_ON(atomic_read(&uobj->usecnt) != -1);
+               break;
+       }
 #endif
 }
 
@@ -164,7 +173,7 @@ static int uverbs_destroy_uobject(struct ib_uobject *uobj,
        unsigned long flags;
        int ret;
 
-       assert_uverbs_usecnt(uobj, true);
+       assert_uverbs_usecnt(uobj, UVERBS_LOOKUP_WRITE);
 
        if (uobj->object) {
                ret = uobj->type->type_class->remove_commit(uobj, reason);
@@ -229,13 +238,13 @@ struct ib_uobject *__uobj_get_destroy(const struct uverbs_obj_type *type,
        struct ib_uobject *uobj;
        int ret;
 
-       uobj = rdma_lookup_get_uobject(type, ufile, id, true);
+       uobj = rdma_lookup_get_uobject(type, ufile, id, UVERBS_LOOKUP_WRITE);
        if (IS_ERR(uobj))
                return uobj;
 
        ret = rdma_explicit_destroy(uobj);
        if (ret) {
-               rdma_lookup_put_uobject(uobj, true);
+               rdma_lookup_put_uobject(uobj, UVERBS_LOOKUP_WRITE);
                return ERR_PTR(ret);
        }
 
@@ -256,7 +265,7 @@ int __uobj_perform_destroy(const struct uverbs_obj_type *type, u32 id,
        if (IS_ERR(uobj))
                return PTR_ERR(uobj);
 
-       rdma_lookup_put_uobject(uobj, true);
+       rdma_lookup_put_uobject(uobj, UVERBS_LOOKUP_WRITE);
        return success_res;
 }
 
@@ -319,7 +328,8 @@ static int idr_add_uobj(struct ib_uobject *uobj)
 /* Returns the ib_uobject or an error. The caller should check for IS_ERR. */
 static struct ib_uobject *
 lookup_get_idr_uobject(const struct uverbs_obj_type *type,
-                      struct ib_uverbs_file *ufile, s64 id, bool exclusive)
+                      struct ib_uverbs_file *ufile, s64 id,
+                      enum rdma_lookup_mode mode)
 {
        struct ib_uobject *uobj;
        unsigned long idrno = id;
@@ -349,9 +359,10 @@ free:
        return uobj;
 }
 
-static struct ib_uobject *lookup_get_fd_uobject(const struct uverbs_obj_type *type,
-                                               struct ib_uverbs_file *ufile,
-                                               s64 id, bool exclusive)
+static struct ib_uobject *
+lookup_get_fd_uobject(const struct uverbs_obj_type *type,
+                     struct ib_uverbs_file *ufile, s64 id,
+                     enum rdma_lookup_mode mode)
 {
        struct file *f;
        struct ib_uobject *uobject;
@@ -362,7 +373,7 @@ static struct ib_uobject *lookup_get_fd_uobject(const struct uverbs_obj_type *ty
        if (fdno != id)
                return ERR_PTR(-EINVAL);
 
-       if (exclusive)
+       if (mode != UVERBS_LOOKUP_READ)
                return ERR_PTR(-EOPNOTSUPP);
 
        f = fget(fdno);
@@ -386,12 +397,12 @@ static struct ib_uobject *lookup_get_fd_uobject(const struct uverbs_obj_type *ty
 
 struct ib_uobject *rdma_lookup_get_uobject(const struct uverbs_obj_type *type,
                                           struct ib_uverbs_file *ufile, s64 id,
-                                          bool exclusive)
+                                          enum rdma_lookup_mode mode)
 {
        struct ib_uobject *uobj;
        int ret;
 
-       uobj = type->type_class->lookup_get(type, ufile, id, exclusive);
+       uobj = type->type_class->lookup_get(type, ufile, id, mode);
        if (IS_ERR(uobj))
                return uobj;
 
@@ -400,13 +411,13 @@ struct ib_uobject *rdma_lookup_get_uobject(const struct uverbs_obj_type *type,
                goto free;
        }
 
-       ret = uverbs_try_lock_object(uobj, exclusive);
+       ret = uverbs_try_lock_object(uobj, mode);
        if (ret)
                goto free;
 
        return uobj;
 free:
-       uobj->type->type_class->lookup_put(uobj, exclusive);
+       uobj->type->type_class->lookup_put(uobj, mode);
        uverbs_uobject_put(uobj);
        return ERR_PTR(ret);
 }
@@ -643,32 +654,39 @@ void rdma_alloc_abort_uobject(struct ib_uobject *uobj)
        uverbs_destroy_uobject(uobj, RDMA_REMOVE_ABORT);
 }
 
-static void lookup_put_idr_uobject(struct ib_uobject *uobj, bool exclusive)
+static void lookup_put_idr_uobject(struct ib_uobject *uobj,
+                                  enum rdma_lookup_mode mode)
 {
 }
 
-static void lookup_put_fd_uobject(struct ib_uobject *uobj, bool exclusive)
+static void lookup_put_fd_uobject(struct ib_uobject *uobj,
+                                 enum rdma_lookup_mode mode)
 {
        struct file *filp = uobj->object;
 
-       WARN_ON(exclusive);
+       WARN_ON(mode != UVERBS_LOOKUP_READ);
        /* This indirectly calls uverbs_close_fd and free the object */
        fput(filp);
 }
 
-void rdma_lookup_put_uobject(struct ib_uobject *uobj, bool exclusive)
+void rdma_lookup_put_uobject(struct ib_uobject *uobj,
+                            enum rdma_lookup_mode mode)
 {
-       assert_uverbs_usecnt(uobj, exclusive);
-       uobj->type->type_class->lookup_put(uobj, exclusive);
+       assert_uverbs_usecnt(uobj, mode);
+       uobj->type->type_class->lookup_put(uobj, mode);
        /*
         * In order to unlock an object, either decrease its usecnt for
         * read access or zero it in case of exclusive access. See
         * uverbs_try_lock_object for locking schema information.
         */
-       if (!exclusive)
+       switch (mode) {
+       case UVERBS_LOOKUP_READ:
                atomic_dec(&uobj->usecnt);
-       else
+               break;
+       case UVERBS_LOOKUP_WRITE:
                atomic_set(&uobj->usecnt, 0);
+               break;
+       }
 
        /* Pairs with the kref obtained by type->lookup_get */
        uverbs_uobject_put(uobj);
@@ -710,7 +728,7 @@ void uverbs_close_fd(struct file *f)
                 * method from being invoked. Meaning we can always get the
                 * write lock here, or we have a kernel bug.
                 */
-               WARN_ON(uverbs_try_lock_object(uobj, true));
+               WARN_ON(uverbs_try_lock_object(uobj, UVERBS_LOOKUP_WRITE));
                uverbs_destroy_uobject(uobj, RDMA_REMOVE_CLOSE);
                up_read(&ufile->hw_destroy_rwsem);
        }
@@ -807,7 +825,7 @@ static int __uverbs_cleanup_ufile(struct ib_uverbs_file *ufile,
                 * if we hit this WARN_ON, that means we are
                 * racing with a lookup_get.
                 */
-               WARN_ON(uverbs_try_lock_object(obj, true));
+               WARN_ON(uverbs_try_lock_object(obj, UVERBS_LOOKUP_WRITE));
                if (!uverbs_destroy_uobject(obj, reason))
                        ret = 0;
        }
@@ -890,10 +908,12 @@ uverbs_get_uobject_from_file(const struct uverbs_obj_type *type_attrs,
 {
        switch (access) {
        case UVERBS_ACCESS_READ:
-               return rdma_lookup_get_uobject(type_attrs, ufile, id, false);
+               return rdma_lookup_get_uobject(type_attrs, ufile, id,
+                                              UVERBS_LOOKUP_READ);
        case UVERBS_ACCESS_DESTROY:
        case UVERBS_ACCESS_WRITE:
-               return rdma_lookup_get_uobject(type_attrs, ufile, id, true);
+               return rdma_lookup_get_uobject(type_attrs, ufile, id,
+                                              UVERBS_LOOKUP_WRITE);
        case UVERBS_ACCESS_NEW:
                return rdma_alloc_begin_uobject(type_attrs, ufile);
        default:
@@ -916,13 +936,13 @@ int uverbs_finalize_object(struct ib_uobject *uobj,
 
        switch (access) {
        case UVERBS_ACCESS_READ:
-               rdma_lookup_put_uobject(uobj, false);
+               rdma_lookup_put_uobject(uobj, UVERBS_LOOKUP_READ);
                break;
        case UVERBS_ACCESS_WRITE:
-               rdma_lookup_put_uobject(uobj, true);
+               rdma_lookup_put_uobject(uobj, UVERBS_LOOKUP_WRITE);
                break;
        case UVERBS_ACCESS_DESTROY:
-               rdma_lookup_put_uobject(uobj, true);
+               rdma_lookup_put_uobject(uobj, UVERBS_LOOKUP_WRITE);
                break;
        case UVERBS_ACCESS_NEW:
                if (commit)

diff --git a/include/rdma/uverbs_std_types.h b/include/rdma/uverbs_std_types.h
index c2f89e4..8c54e14 100644 (file)
--- a/include/rdma/uverbs_std_types.h
+++ b/include/rdma/uverbs_std_types.h
@@ -58,11 +58,12 @@ static inline const struct uverbs_object_tree_def *uverbs_default_get_objects(vo
 
 #define uobj_get_read(_type, _id, _ufile)                                      \
        rdma_lookup_get_uobject(uobj_get_type(_type), _ufile,                  \
-                               _uobj_check_id(_id), false)
+                               _uobj_check_id(_id), UVERBS_LOOKUP_READ)
 
 #define ufd_get_read(_type, _fdnum, _ufile)                                    \
        rdma_lookup_get_uobject(uobj_get_type(_type), _ufile,                  \
-                               (_fdnum)*typecheck(s32, _fdnum), false)
+                               (_fdnum)*typecheck(s32, _fdnum),               \
+                               UVERBS_LOOKUP_READ)
 
 static inline void *_uobj_get_obj_read(struct ib_uobject *uobj)
 {
@@ -76,7 +77,7 @@ static inline void *_uobj_get_obj_read(struct ib_uobject *uobj)
 
 #define uobj_get_write(_type, _id, _ufile)                                     \
        rdma_lookup_get_uobject(uobj_get_type(_type), _ufile,                  \
-                               _uobj_check_id(_id), true)
+                               _uobj_check_id(_id), UVERBS_LOOKUP_WRITE)
 
 int __uobj_perform_destroy(const struct uverbs_obj_type *type, u32 id,
                           struct ib_uverbs_file *ufile, int success_res);
@@ -92,12 +93,12 @@ struct ib_uobject *__uobj_get_destroy(const struct uverbs_obj_type *type,
 
 static inline void uobj_put_destroy(struct ib_uobject *uobj)
 {
-       rdma_lookup_put_uobject(uobj, true);
+       rdma_lookup_put_uobject(uobj, UVERBS_LOOKUP_WRITE);
 }
 
 static inline void uobj_put_read(struct ib_uobject *uobj)
 {
-       rdma_lookup_put_uobject(uobj, false);
+       rdma_lookup_put_uobject(uobj, UVERBS_LOOKUP_READ);
 }
 
 #define uobj_put_obj_read(_obj)                                        \
@@ -105,7 +106,7 @@ static inline void uobj_put_read(struct ib_uobject *uobj)
 
 static inline void uobj_put_write(struct ib_uobject *uobj)
 {
-       rdma_lookup_put_uobject(uobj, true);
+       rdma_lookup_put_uobject(uobj, UVERBS_LOOKUP_WRITE);
 }
 
 static inline int __must_check uobj_alloc_commit(struct ib_uobject *uobj,

diff --git a/include/rdma/uverbs_types.h b/include/rdma/uverbs_types.h
index 875dd8c..0676672 100644 (file)
--- a/include/rdma/uverbs_types.h
+++ b/include/rdma/uverbs_types.h
@@ -38,6 +38,11 @@
 
 struct uverbs_obj_type;
 
+enum rdma_lookup_mode {
+       UVERBS_LOOKUP_READ,
+       UVERBS_LOOKUP_WRITE,
+};
+
 /*
  * The following sequences are valid:
  * Success flow:
@@ -78,8 +83,8 @@ struct uverbs_obj_type_class {
 
        struct ib_uobject *(*lookup_get)(const struct uverbs_obj_type *type,
                                         struct ib_uverbs_file *ufile, s64 id,
-                                        bool exclusive);
-       void (*lookup_put)(struct ib_uobject *uobj, bool exclusive);
+                                        enum rdma_lookup_mode mode);
+       void (*lookup_put)(struct ib_uobject *uobj, enum rdma_lookup_mode mode);
        /* This does not consume the kref on uobj */
        int __must_check (*remove_commit)(struct ib_uobject *uobj,
                                          enum rdma_remove_reason why);
@@ -116,9 +121,10 @@ struct uverbs_obj_idr_type {
 };
 
 struct ib_uobject *rdma_lookup_get_uobject(const struct uverbs_obj_type *type,
-                                          struct ib_uverbs_file *ufile,
-                                          s64 id, bool exclusive);
-void rdma_lookup_put_uobject(struct ib_uobject *uobj, bool exclusive);
+                                          struct ib_uverbs_file *ufile, s64 id,
+                                          enum rdma_lookup_mode mode);
+void rdma_lookup_put_uobject(struct ib_uobject *uobj,
+                            enum rdma_lookup_mode mode);
 struct ib_uobject *rdma_alloc_begin_uobject(const struct uverbs_obj_type *type,
                                            struct ib_uverbs_file *ufile);
 void rdma_alloc_abort_uobject(struct ib_uobject *uobj);