From 0c1d1917c547c8e787fb58e20e2de577453c980c Mon Sep 17 00:00:00 2001 From: Chris Metcalf Date: Wed, 7 Aug 2013 14:07:03 -0400 Subject: tile: support simulator notification for ET_DYN objects The tile code notifies the simulator of new ET_EXEC objects starting to execute so that tracing code can properly annotate the objects. However, we didn't support ET_DYN executables like ld.so, so we didn't properly load symbols, etc. This change enables that support; we use a variant of the SIM_CONTROL_DLOPEN simulator notification that newer simulators will recognize and use to set the base address for the next SIM_CONTROL_OS_EXEC notification. Signed-off-by: Chris Metcalf --- arch/tile/mm/elf.c | 62 ++++++++++++++++++++++++++++++++++++++++++------------ 1 file changed, 48 insertions(+), 14 deletions(-) diff --git a/arch/tile/mm/elf.c b/arch/tile/mm/elf.c index 743c951c61b0..1691b81b2b0c 100644 --- a/arch/tile/mm/elf.c +++ b/arch/tile/mm/elf.c @@ -21,7 +21,7 @@ #include #include #include -#include +#include /* Notify a running simulator, if any, that an exec just occurred. */ static void sim_notify_exec(const char *binary_name) @@ -38,21 +38,55 @@ static void sim_notify_exec(const char *binary_name) static int notify_exec(struct mm_struct *mm) { - int retval = 0; /* failure */ - - if (mm->exe_file) { - char *buf = (char *) __get_free_page(GFP_KERNEL); - if (buf) { - char *path = d_path(&mm->exe_file->f_path, - buf, PAGE_SIZE); - if (!IS_ERR(path)) { - sim_notify_exec(path); - retval = 1; - } - free_page((unsigned long)buf); + char *buf, *path; + struct vm_area_struct *vma; + + if (!sim_is_simulator()) + return 1; + + if (mm->exe_file == NULL) + return 0; + + for (vma = current->mm->mmap; ; vma = vma->vm_next) { + if (vma == NULL) + return 0; + if (vma->vm_file == mm->exe_file) + break; + } + + buf = (char *) __get_free_page(GFP_KERNEL); + if (buf == NULL) + return 0; + + path = d_path(&mm->exe_file->f_path, buf, PAGE_SIZE); + if (IS_ERR(path)) { + free_page((unsigned long)buf); + return 0; + } + + /* + * Notify simulator of an ET_DYN object so we know the load address. + * The somewhat cryptic overuse of SIM_CONTROL_DLOPEN allows us + * to be backward-compatible with older simulator releases. + */ + if (vma->vm_start == (ELF_ET_DYN_BASE & PAGE_MASK)) { + char buf[64]; + int i; + + snprintf(buf, sizeof(buf), "0x%lx:@", vma->vm_start); + for (i = 0; ; ++i) { + char c = buf[i]; + __insn_mtspr(SPR_SIM_CONTROL, + (SIM_CONTROL_DLOPEN + | (c << _SIM_CONTROL_OPERATOR_BITS))); + if (c == '\0') + break; } } - return retval; + + sim_notify_exec(path); + free_page((unsigned long)buf); + return 1; } /* Notify a running simulator, if any, that we loaded an interpreter. */ -- cgit v1.2.3