Revert r337978: Rework rtld's TLS Variant I implementation to match r326794

Michal Meloun reports that it breaks ctype (isspace()..) related
functions on armv7 so back out while we diagnose the issue.

Reported by:	Michal Meloun <melounmichal@gmail.com>

7 files changed, 20 insertions, 73 deletions

diff --git a/libexec/rtld-elf/aarch64/rtld_machdep.h b/libexec/rtld-elf/aarch64/rtld_machdep.h
index 9ff53d900aaa..eb72a61b6fe8 100644
--- a/libexec/rtld-elf/aarch64/rtld_machdep.h
+++ b/libexec/rtld-elf/aarch64/rtld_machdep.h
@@ -69,8 +69,6 @@ Elf_Addr reloc_jmpslot(Elf_Addr *where, Elf_Addr target,
 #define	calculate_tls_offset(prev_offset, prev_size, size, align) \
 	round(prev_offset + prev_size, align)
 #define	calculate_tls_end(off, size) 	((off) + (size))
-#define calculate_tls_post_size(align) \
-	round(TLS_TCB_SIZE, align) - TLS_TCB_SIZE
 
 #define	TLS_TCB_SIZE	16
 typedef struct {
diff --git a/libexec/rtld-elf/arm/rtld_machdep.h b/libexec/rtld-elf/arm/rtld_machdep.h
index 030c83cdc7f4..926971c41524 100644
--- a/libexec/rtld-elf/arm/rtld_machdep.h
+++ b/libexec/rtld-elf/arm/rtld_machdep.h
@@ -69,8 +69,6 @@ typedef struct {
 #define calculate_tls_offset(prev_offset, prev_size, size, align) \
     round(prev_offset + prev_size, align)
 #define calculate_tls_end(off, size)    ((off) + (size))
-#define calculate_tls_post_size(align) \
-    round(TLS_TCB_SIZE, align) - TLS_TCB_SIZE
 	
 extern void *__tls_get_addr(tls_index *ti);
 
diff --git a/libexec/rtld-elf/mips/rtld_machdep.h b/libexec/rtld-elf/mips/rtld_machdep.h
index e20c32794530..0cfb665e7898 100644
--- a/libexec/rtld-elf/mips/rtld_machdep.h
+++ b/libexec/rtld-elf/mips/rtld_machdep.h
@@ -64,11 +64,10 @@ typedef struct {
 #define round(size, align) \
     (((size) + (align) - 1) & ~((align) - 1))
 #define calculate_first_tls_offset(size, align) \
-    TLS_TCB_SIZE
+    round(TLS_TCB_SIZE, align)
 #define calculate_tls_offset(prev_offset, prev_size, size, align) \
     round(prev_offset + prev_size, align)
 #define calculate_tls_end(off, size)    ((off) + (size))
-#define calculate_tls_post_size(align)  0
 
 extern void *__tls_get_addr(tls_index *ti);
 
diff --git a/libexec/rtld-elf/powerpc/rtld_machdep.h b/libexec/rtld-elf/powerpc/rtld_machdep.h
index c89ec4817401..584ccd977ec0 100644
--- a/libexec/rtld-elf/powerpc/rtld_machdep.h
+++ b/libexec/rtld-elf/powerpc/rtld_machdep.h
@@ -74,11 +74,10 @@ void _rtld_powerpc_pltcall(void);
 #define round(size, align) \
     (((size) + (align) - 1) & ~((align) - 1))
 #define calculate_first_tls_offset(size, align) \
-    TLS_TCB_SIZE
+    round(8, align)
 #define calculate_tls_offset(prev_offset, prev_size, size, align) \
     round(prev_offset + prev_size, align)
 #define calculate_tls_end(off, size)    ((off) + (size))
-#define calculate_tls_post_size(align)  0
  
 typedef struct {
 	unsigned long ti_module;
diff --git a/libexec/rtld-elf/powerpc64/rtld_machdep.h b/libexec/rtld-elf/powerpc64/rtld_machdep.h
index b0f71d312db0..cf42db426f4f 100644
--- a/libexec/rtld-elf/powerpc64/rtld_machdep.h
+++ b/libexec/rtld-elf/powerpc64/rtld_machdep.h
@@ -66,11 +66,10 @@ Elf_Addr reloc_jmpslot(Elf_Addr *where, Elf_Addr target,
 #define round(size, align) \
     (((size) + (align) - 1) & ~((align) - 1))
 #define calculate_first_tls_offset(size, align) \
-    TLS_TCB_SIZE
+    round(16, align)
 #define calculate_tls_offset(prev_offset, prev_size, size, align) \
     round(prev_offset + prev_size, align)
 #define calculate_tls_end(off, size)    ((off) + (size))
-#define calculate_tls_post_size(align)  0
  
 typedef struct {
 	unsigned long ti_module;
diff --git a/libexec/rtld-elf/riscv/rtld_machdep.h b/libexec/rtld-elf/riscv/rtld_machdep.h
index 1737fa73ff8b..bb1f6868f1ac 100644
--- a/libexec/rtld-elf/riscv/rtld_machdep.h
+++ b/libexec/rtld-elf/riscv/rtld_machdep.h
@@ -89,11 +89,10 @@ Elf_Addr reloc_jmpslot(Elf_Addr *where, Elf_Addr target,
 #define round(size, align) \
     (((size) + (align) - 1) & ~((align) - 1))
 #define calculate_first_tls_offset(size, align) \
-    TLS_TCB_SIZE
+    round(16, align)
 #define calculate_tls_offset(prev_offset, prev_size, size, align) \
     round(prev_offset + prev_size, align)
 #define calculate_tls_end(off, size)    ((off) + (size))
-#define calculate_tls_post_size(align)  0
 
 typedef struct {
 	unsigned long ti_module;
diff --git a/libexec/rtld-elf/rtld.c b/libexec/rtld-elf/rtld.c
index dfd0388478f9..43240568b3e8 100644
--- a/libexec/rtld-elf/rtld.c
+++ b/libexec/rtld-elf/rtld.c
@@ -4693,87 +4693,47 @@ tls_get_addr_common(Elf_Addr **dtvp, int index, size_t offset)
     defined(__powerpc__) || defined(__riscv)
 
 /*
- * Return pointer to allocated TLS block
- */
-static void *
-get_tls_block_ptr(void *tcb, size_t tcbsize)
-{
-    size_t extra_size, post_size, pre_size, tls_block_size;
-    size_t tls_init_align;
-
-    tls_init_align = MAX(obj_main->tlsalign, 1);
-
-    /* Compute fragments sizes. */
-    extra_size = tcbsize - TLS_TCB_SIZE;
-    post_size = calculate_tls_post_size(tls_init_align);
-    tls_block_size = tcbsize + post_size;
-    pre_size = roundup2(tls_block_size, tls_init_align) - tls_block_size;
-
-    return ((char *)tcb - pre_size - extra_size);
-}
-
-/*
  * Allocate Static TLS using the Variant I method.
- *
- * For details on the layout, see lib/libc/gen/tls.c.
- *
- * NB: rtld's tls_static_space variable includes TLS_TCB_SIZE and post_size as
- *     it is based on tls_last_offset, and TLS offsets here are really TCB
- *     offsets, whereas libc's tls_static_space is just the executable's static
- *     TLS segment.
  */
 void *
 allocate_tls(Obj_Entry *objs, void *oldtcb, size_t tcbsize, size_t tcbalign)
 {
     Obj_Entry *obj;
-    char *tls_block;
-    Elf_Addr *dtv, **tcb;
+    char *tcb;
+    Elf_Addr **tls;
+    Elf_Addr *dtv;
     Elf_Addr addr;
     int i;
-    size_t extra_size, maxalign, post_size, pre_size, tls_block_size;
-    size_t tls_init_align;
 
     if (oldtcb != NULL && tcbsize == TLS_TCB_SIZE)
 	return (oldtcb);
 
     assert(tcbsize >= TLS_TCB_SIZE);
-    maxalign = MAX(tcbalign, tls_static_max_align);
-    tls_init_align = MAX(obj_main->tlsalign, 1);
-
-    /* Compute fragmets sizes. */
-    extra_size = tcbsize - TLS_TCB_SIZE;
-    post_size = calculate_tls_post_size(tls_init_align);
-    tls_block_size = tcbsize + post_size;
-    pre_size = roundup2(tls_block_size, tls_init_align) - tls_block_size;
-    tls_block_size += pre_size + tls_static_space - TLS_TCB_SIZE - post_size;
-
-    /* Allocate whole TLS block */
-    tls_block = malloc_aligned(tls_block_size, maxalign);
-    tcb = (Elf_Addr **)(tls_block + pre_size + extra_size);
+    tcb = xcalloc(1, tls_static_space - TLS_TCB_SIZE + tcbsize);
+    tls = (Elf_Addr **)(tcb + tcbsize - TLS_TCB_SIZE);
 
     if (oldtcb != NULL) {
-	memcpy(tls_block, get_tls_block_ptr(oldtcb, tcbsize),
-	    tls_static_space);
-	free_aligned(get_tls_block_ptr(oldtcb, tcbsize));
+	memcpy(tls, oldtcb, tls_static_space);
+	free(oldtcb);
 
 	/* Adjust the DTV. */
-	dtv = tcb[0];
+	dtv = tls[0];
 	for (i = 0; i < dtv[1]; i++) {
 	    if (dtv[i+2] >= (Elf_Addr)oldtcb &&
 		dtv[i+2] < (Elf_Addr)oldtcb + tls_static_space) {
-		dtv[i+2] = dtv[i+2] - (Elf_Addr)oldtcb + (Elf_Addr)tcb;
+		dtv[i+2] = dtv[i+2] - (Elf_Addr)oldtcb + (Elf_Addr)tls;
 	    }
 	}
     } else {
 	dtv = xcalloc(tls_max_index + 2, sizeof(Elf_Addr));
-	tcb[0] = dtv;
+	tls[0] = dtv;
 	dtv[0] = tls_dtv_generation;
 	dtv[1] = tls_max_index;
 
 	for (obj = globallist_curr(objs); obj != NULL;
 	  obj = globallist_next(obj)) {
 	    if (obj->tlsoffset > 0) {
-		addr = (Elf_Addr)tcb + obj->tlsoffset;
+		addr = (Elf_Addr)tls + obj->tlsoffset;
 		if (obj->tlsinitsize > 0)
 		    memcpy((void*) addr, obj->tlsinit, obj->tlsinitsize);
 		if (obj->tlssize > obj->tlsinitsize)
@@ -4792,19 +4752,14 @@ free_tls(void *tcb, size_t tcbsize, size_t tcbalign)
 {
     Elf_Addr *dtv;
     Elf_Addr tlsstart, tlsend;
-    size_t post_size;
-    size_t dtvsize, i, tls_init_align;
+    int dtvsize, i;
 
     assert(tcbsize >= TLS_TCB_SIZE);
-    tls_init_align = MAX(obj_main->tlsalign, 1);
-
-    /* Compute fragments sizes. */
-    post_size = calculate_tls_post_size(tls_init_align);
 
-    tlsstart = (Elf_Addr)tcb + TLS_TCB_SIZE + post_size;
-    tlsend = (Elf_Addr)tcb + tls_static_space;
+    tlsstart = (Elf_Addr)tcb + tcbsize - TLS_TCB_SIZE;
+    tlsend = tlsstart + tls_static_space;
 
-    dtv = *(Elf_Addr **)tcb;
+    dtv = *(Elf_Addr **)tlsstart;
     dtvsize = dtv[1];
     for (i = 0; i < dtvsize; i++) {
 	if (dtv[i+2] && (dtv[i+2] < tlsstart || dtv[i+2] >= tlsend)) {
@@ -4812,7 +4767,7 @@ free_tls(void *tcb, size_t tcbsize, size_t tcbalign)
 	}
     }
     free(dtv);
-    free_aligned(get_tls_block_ptr(tcb, tcbsize));
+    free(tcb);
 }
 
 #endif