Make setjmp.h prototypes comply with the C standard

Instead of having a custom implementation of setjmp() and longjmp() it
is better to follow the C standard.

The comments in setjmp.h are no longer needed as there are no deviations
from the expected one, so they have been removed.

All SDEI code that relied on them has been fixed to use the new function
prototypes and structs.

Change-Id: I6cd2e21cb5a5bcf81ba12283f2e4c067bd5172ca
Signed-off-by: Antonio Nino Diaz <[email protected]>

diff --git a/include/arch/aarch64/setjmp.h b/include/arch/aarch64/setjmp.h
index bbfe1df434b097c7790bc2dafc954efc159895e4..f7991fddbdd88407113b11b02b01273b5b72edec 100644 (file)
--- a/include/arch/aarch64/setjmp.h
+++ b/include/arch/aarch64/setjmp.h
@@ -1,5 +1,5 @@
 /*
- * Copyright (c) 2018, ARM Limited and Contributors. All rights reserved.
+ * Copyright (c) 2018-2019, ARM Limited and Contributors. All rights reserved.
  *
  * SPDX-License-Identifier: BSD-3-Clause
  */
@@ -14,46 +14,20 @@
 #define JMP_CTX_X27    0x40
 #define JMP_CTX_X29    0x50
 #define JMP_CTX_SP     0x60
-#define JMP_CTX_END    0x70
+#define JMP_CTX_END    0x70 /* Aligned to 16 bytes */
 
 #define JMP_SIZE       (JMP_CTX_END >> 3)
 
 #ifndef __ASSEMBLY__
 
+#include <cdefs.h>
 #include <stdint.h>
 
 /* Jump buffer hosting x18 - x30 and sp_el0 registers */
-struct jmpbuf {
-       uint64_t buf[JMP_SIZE];
-} __aligned(16);
+typedef uint64_t jmp_buf[JMP_SIZE] __aligned(16);
 
-
-/*
- * Set a jump point, and populate the jump buffer with context information so
- * that longjmp() can jump later. The caller must adhere to the following
- * conditions:
- *
- *  - After calling this function, the stack must not be shrunk. The contents of
- *    the stack must not be changed either.
- *
- *  - If the caller were to 'return', the buffer must be considered invalid, and
- *    must not be used with longjmp().
- *
- * The caller will observe this function returning at two distinct
- * circumstances, each with different return values:
- *
- *  - Zero, when the buffer is setup;
- *
- *  - Non-zero, when a call to longjmp() is made (presumably by one of the
- *    callee functions) with the same jump buffer.
- */
-int setjmp(struct jmpbuf *buf);
-
-/*
- * Reset execution to a jump point, and restore context information according to
- * the jump buffer populated by setjmp().
- */
-void longjmp(struct jmpbuf *buf);
+int setjmp(jmp_buf env);
+__dead2 void longjmp(jmp_buf env, int val);
 
 #endif /* __ASSEMBLY__ */
 #endif /* SETJMP_H */

diff --git a/lib/aarch64/setjmp.S b/lib/aarch64/setjmp.S
index 9060cb7569fb412050628e9f0ad6062af4b08784..9d9eb49ba445ebb6a45482865917f323d59fe25c 100644 (file)
--- a/lib/aarch64/setjmp.S
+++ b/lib/aarch64/setjmp.S
@@ -1,5 +1,5 @@
 /*
- * Copyright (c) 2018, ARM Limited and Contributors. All rights reserved.
+ * Copyright (c) 2018-2019, ARM Limited and Contributors. All rights reserved.
  *
  * SPDX-License-Identifier: BSD-3-Clause
  */
@@ -12,10 +12,7 @@
        .globl  longjmp
 
 /*
- * int setjmp(struct jmpbuf *buf);
- *
- * Sets a jump point in the buffer specified in x0. Returns 0 to the caller when
- * when setting up the jump, and 1 when returning from the jump.
+ * int setjmp(jmp_buf env);
  */
 func setjmp
        mov     x7, sp
@@ -34,9 +31,7 @@ endfunc setjmp
 
 
 /*
- * void longjmp(struct jmpbuf *buf);
- *
- * Return to a jump point setup by setjmp()
+ * void longjmp(jmp_buf env, int val);
  */
 func longjmp
        ldp     x7, xzr, [x0, #JMP_CTX_SP]
@@ -60,6 +55,7 @@ func longjmp
 
        mov     sp, x7
 
-       mov     x0, #1
+       ands    x0, x1, x1 /* Move val to x0 and set flags */
+       cinc    x0, x0, eq /* If val is 0, return 1 */
        ret
 endfunc longjmp

diff --git a/services/std_svc/sdei/sdei_dispatch.S b/services/std_svc/sdei/sdei_dispatch.S
index a7a4a40f73922588b19dce7ee735c7159d127c86..8449e4b5aba8b04c8ac42c65f8328f409d3e17c0 100644 (file)
--- a/services/std_svc/sdei/sdei_dispatch.S
+++ b/services/std_svc/sdei/sdei_dispatch.S
@@ -1,5 +1,5 @@
 /*
- * Copyright (c) 2018, ARM Limited and Contributors. All rights reserved.
+ * Copyright (c) 2018-2019, ARM Limited and Contributors. All rights reserved.
  *
  * SPDX-License-Identifier: BSD-3-Clause
  */
@@ -9,7 +9,7 @@
        .globl  begin_sdei_synchronous_dispatch
 
 /*
- * void begin_sdei_synchronous_dispatch(struct jmpbuf *buffer);
+ * void begin_sdei_synchronous_dispatch(jmp_buf *buffer);
  *
  * Begin SDEI dispatch synchronously by setting up a jump point, and exiting
  * EL3. This jump point is jumped to by the dispatcher after the event is

diff --git a/services/std_svc/sdei/sdei_intr_mgmt.c b/services/std_svc/sdei/sdei_intr_mgmt.c
index b8799cd49fafe08f647f5e769098169c25852fd3..fa1d3d2839727d92ede63a2ff3654b506cf7be18 100644 (file)
--- a/services/std_svc/sdei/sdei_intr_mgmt.c
+++ b/services/std_svc/sdei/sdei_intr_mgmt.c
@@ -1,5 +1,5 @@
 /*
- * Copyright (c) 2017-2018, ARM Limited and Contributors. All rights reserved.
+ * Copyright (c) 2017-2019, ARM Limited and Contributors. All rights reserved.
  *
  * SPDX-License-Identifier: BSD-3-Clause
  */
@@ -31,7 +31,7 @@
 typedef struct sdei_dispatch_context {
        sdei_ev_map_t *map;
        uint64_t x[SDEI_SAVED_GPREGS];
-       struct jmpbuf *dispatch_jmp;
+       jmp_buf *dispatch_jmp;
 
        /* Exception state registers */
        uint64_t elr_el3;
@@ -236,7 +236,7 @@ static cpu_context_t *restore_and_resume_ns_context(void)
  * SDEI client.
  */
 static void setup_ns_dispatch(sdei_ev_map_t *map, sdei_entry_t *se,
-               cpu_context_t *ctx, struct jmpbuf *dispatch_jmp)
+               cpu_context_t *ctx, jmp_buf *dispatch_jmp)
 {
        sdei_dispatch_context_t *disp_ctx;
 
@@ -347,7 +347,7 @@ int sdei_intr_handler(uint32_t intr_raw, uint32_t flags, void *handle,
        unsigned int sec_state;
        sdei_cpu_state_t *state;
        uint32_t intr;
-       struct jmpbuf dispatch_jmp;
+       jmp_buf dispatch_jmp;
        const uint64_t mpidr = read_mpidr_el1();
 
        /*
@@ -529,7 +529,7 @@ int sdei_dispatch_event(int ev_num)
        cpu_context_t *ns_ctx;
        sdei_dispatch_context_t *disp_ctx;
        sdei_cpu_state_t *state;
-       struct jmpbuf dispatch_jmp;
+       jmp_buf dispatch_jmp;
 
        /* Can't dispatch if events are masked on this PE */
        state = sdei_get_this_pe_state();
@@ -595,9 +595,9 @@ int sdei_dispatch_event(int ev_num)
        return 0;
 }
 
-static void end_sdei_synchronous_dispatch(struct jmpbuf *buffer)
+static void end_sdei_synchronous_dispatch(jmp_buf *buffer)
 {
-       longjmp(buffer);
+       longjmp(*buffer, 1);
 }
 
 int sdei_event_complete(bool resume, uint64_t pc)

diff --git a/services/std_svc/sdei/sdei_private.h b/services/std_svc/sdei/sdei_private.h
index 148643129ca6a59c20a0dd9d4ca93cb04e687b8b..8cc66e76d9d70ba731faee1a77a9a855d4642e06 100644 (file)
--- a/services/std_svc/sdei/sdei_private.h
+++ b/services/std_svc/sdei/sdei_private.h
@@ -243,6 +243,6 @@ int64_t sdei_pe_mask(void);
 int sdei_intr_handler(uint32_t intr_raw, uint32_t flags, void *handle,
                void *cookie);
 bool can_sdei_state_trans(sdei_entry_t *se, sdei_action_t act);
-void begin_sdei_synchronous_dispatch(struct jmpbuf *buffer);
+void begin_sdei_synchronous_dispatch(jmp_buf *buffer);
 
 #endif /* SDEI_PRIVATE_H */