[PATCH 15/17] vdso: Remove remnants of architecture-specific random state storage

[Thomas Weißschuh]

All users of the random vDSO are using the generic storage
implementation. Remove the now unnecessary compatibility accessor
functions and symbols.

Co-developed-by: Nam Cao <namcao@xxxxxxxxxxxxx>
Signed-off-by: Nam Cao <namcao@xxxxxxxxxxxxx>
Signed-off-by: Thomas Weißschuh <thomas.weissschuh@xxxxxxxxxxxxx>
---
 drivers/char/random.c   | 6 +++---
 include/vdso/datapage.h | 8 --------
 lib/vdso/getrandom.c    | 4 ++--
 3 files changed, 5 insertions(+), 13 deletions(-)

diff --git a/drivers/char/random.c b/drivers/char/random.c
index 23ee76bbb4aa728274bf9980a60b863216d88797..84efda7bede348401db2ed1c443e5ab2bc5dbd2b 100644
--- a/drivers/char/random.c
+++ b/drivers/char/random.c
@@ -278,7 +278,7 @@ static void crng_reseed(struct work_struct *work)
 	WRITE_ONCE(base_crng.generation, next_gen);
 #ifdef CONFIG_VDSO_GETRANDOM
 	/* base_crng.generation's invalid value is ULONG_MAX, while
-	 * _vdso_rng_data.generation's invalid value is 0, so add one to the
+	 * vdso_k_rng_data->generation's invalid value is 0, so add one to the
 	 * former to arrive at the latter. Use smp_store_release so that this
 	 * is ordered with the write above to base_crng.generation. Pairs with
 	 * the smp_rmb() before the syscall in the vDSO code.
@@ -290,7 +290,7 @@ static void crng_reseed(struct work_struct *work)
 	 * because the vDSO side only checks whether the value changed, without
 	 * actually using or interpreting the value.
 	 */
-	smp_store_release((unsigned long *)&__arch_get_k_vdso_rng_data()->generation, next_gen + 1);
+	smp_store_release((unsigned long *)&vdso_k_rng_data->generation, next_gen + 1);
 #endif
 	if (!static_branch_likely(&crng_is_ready))
 		crng_init = CRNG_READY;
@@ -743,7 +743,7 @@ static void __cold _credit_init_bits(size_t bits)
 			queue_work(system_unbound_wq, &set_ready);
 		atomic_notifier_call_chain(&random_ready_notifier, 0, NULL);
 #ifdef CONFIG_VDSO_GETRANDOM
-		WRITE_ONCE(__arch_get_k_vdso_rng_data()->is_ready, true);
+		WRITE_ONCE(vdso_k_rng_data->is_ready, true);
 #endif
 		wake_up_interruptible(&crng_init_wait);
 		kill_fasync(&fasync, SIGIO, POLL_IN);
diff --git a/include/vdso/datapage.h b/include/vdso/datapage.h
index b3227f1cf62895aa60ce0ca96afa42259f4771f9..0fc240c08e0f7cf596135eed18dd6f06011917d5 100644
--- a/include/vdso/datapage.h
+++ b/include/vdso/datapage.h
@@ -152,7 +152,6 @@ struct vdso_rng_data {
 #ifndef CONFIG_GENERIC_VDSO_DATA_STORE
 extern struct vdso_time_data _vdso_data[CS_BASES] __attribute__((visibility("hidden")));
 extern struct vdso_time_data _timens_data[CS_BASES] __attribute__((visibility("hidden")));
-extern struct vdso_rng_data _vdso_rng_data __attribute__((visibility("hidden")));
 #else
 extern const struct vdso_time_data vdso_u_time_data[CS_BASES] __attribute__((visibility("hidden")));
 extern const struct vdso_time_data vdso_u_timens_data[CS_BASES] __attribute__((visibility("hidden")));
@@ -211,13 +210,6 @@ static __always_inline const struct vdso_rng_data *__arch_get_vdso_u_rng_data(vo
 {
 	return &vdso_u_rng_data;
 }
-#define __arch_get_vdso_rng_data __arch_get_vdso_u_rng_data
-
-static __always_inline struct vdso_rng_data *__arch_get_vdso_k_rng_data(void)
-{
-	return vdso_k_rng_data;
-}
-#define __arch_get_k_vdso_rng_data __arch_get_vdso_k_rng_data
 #endif /* CONFIG_VDSO_GETRANDOM */
 
 #endif /* CONFIG_GENERIC_VDSO_DATA_STORE */
diff --git a/lib/vdso/getrandom.c b/lib/vdso/getrandom.c
index 938ca539aaa64bc46280ef6dd17aa661126699eb..2ed019a76abca099de33326ef45101cf50f2f778 100644
--- a/lib/vdso/getrandom.c
+++ b/lib/vdso/getrandom.c
@@ -152,7 +152,7 @@ __cvdso_getrandom_data(const struct vdso_rng_data *rng_info, void *buffer, size_
 
 		/*
 		 * Prevent the syscall from being reordered wrt current_generation. Pairs with the
-		 * smp_store_release(&_vdso_rng_data.generation) in random.c.
+		 * smp_store_release(&vdso_k_rng_data.generation) in random.c.
 		 */
 		smp_rmb();
 
@@ -256,5 +256,5 @@ __cvdso_getrandom_data(const struct vdso_rng_data *rng_info, void *buffer, size_
 static __always_inline ssize_t
 __cvdso_getrandom(void *buffer, size_t len, unsigned int flags, void *opaque_state, size_t opaque_len)
 {
-	return __cvdso_getrandom_data(__arch_get_vdso_rng_data(), buffer, len, flags, opaque_state, opaque_len);
+	return __cvdso_getrandom_data(__arch_get_vdso_u_rng_data(), buffer, len, flags, opaque_state, opaque_len);
 }

-- 
2.47.1