diff options
| author | Tiwei Bie <tiwei.btw@antgroup.com> | 2025-08-27 08:57:03 +0800 |
|---|---|---|
| committer | Johannes Berg <johannes.berg@intel.com> | 2025-09-10 14:23:52 +0200 |
| commit | e047f9af9d6948728614f7eea41ba53d5b767e9f (patch) | |
| tree | 42bda26d92b48016f25c9445dd509406e55fe0ab | |
| parent | b765d69a1adf83b969f1f0c8353b80c3c18ef2f7 (diff) | |
um: Centralize stub size calculations
Currently, the stub size is calculated in multiple places. Define
a macro that performs the calculation so that the code is easier
to read and maintain.
Signed-off-by: Tiwei Bie <tiwei.btw@antgroup.com>
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
| -rw-r--r-- | arch/um/include/shared/as-layout.h | 3 | ||||
| -rw-r--r-- | arch/um/kernel/um_arch.c | 4 | ||||
| -rw-r--r-- | arch/x86/um/shared/sysdep/stub_32.h | 2 | ||||
| -rw-r--r-- | arch/x86/um/shared/sysdep/stub_64.h | 2 |
4 files changed, 5 insertions, 6 deletions
diff --git a/arch/um/include/shared/as-layout.h b/arch/um/include/shared/as-layout.h index eacf18ec9d0c..7c7e17bce403 100644 --- a/arch/um/include/shared/as-layout.h +++ b/arch/um/include/shared/as-layout.h @@ -24,7 +24,8 @@ #define STUB_CODE STUB_START #define STUB_DATA (STUB_CODE + UM_KERN_PAGE_SIZE) #define STUB_DATA_PAGES 2 -#define STUB_END (STUB_DATA + STUB_DATA_PAGES * UM_KERN_PAGE_SIZE) +#define STUB_SIZE ((1 + STUB_DATA_PAGES) * UM_KERN_PAGE_SIZE) +#define STUB_END (STUB_START + STUB_SIZE) #ifndef __ASSEMBLER__ diff --git a/arch/um/kernel/um_arch.c b/arch/um/kernel/um_arch.c index 2f5ee045bc7a..6cd464c9095f 100644 --- a/arch/um/kernel/um_arch.c +++ b/arch/um/kernel/um_arch.c @@ -331,9 +331,7 @@ int __init linux_main(int argc, char **argv, char **envp) host_task_size = get_top_address(envp); /* reserve a few pages for the stubs */ - stub_start = host_task_size - STUB_DATA_PAGES * PAGE_SIZE; - /* another page for the code portion */ - stub_start -= PAGE_SIZE; + stub_start = host_task_size - STUB_SIZE; host_task_size = stub_start; /* Limit TASK_SIZE to what is addressable by the page table */ diff --git a/arch/x86/um/shared/sysdep/stub_32.h b/arch/x86/um/shared/sysdep/stub_32.h index df568fc3ceb4..9dc2efaf5df1 100644 --- a/arch/x86/um/shared/sysdep/stub_32.h +++ b/arch/x86/um/shared/sysdep/stub_32.h @@ -129,7 +129,7 @@ static __always_inline void *get_stub_data(void) "subl %0,%%esp ;" \ "movl %1, %%eax ; " \ "call *%%eax ;" \ - :: "i" ((1 + STUB_DATA_PAGES) * UM_KERN_PAGE_SIZE), \ + :: "i" (STUB_SIZE), \ "i" (&fn)) static __always_inline void diff --git a/arch/x86/um/shared/sysdep/stub_64.h b/arch/x86/um/shared/sysdep/stub_64.h index 9cfd31afa769..9fd56954e2e0 100644 --- a/arch/x86/um/shared/sysdep/stub_64.h +++ b/arch/x86/um/shared/sysdep/stub_64.h @@ -133,7 +133,7 @@ static __always_inline void *get_stub_data(void) "subq %0,%%rsp ;" \ "movq %1,%%rax ;" \ "call *%%rax ;" \ - :: "i" ((1 + STUB_DATA_PAGES) * UM_KERN_PAGE_SIZE), \ + :: "i" (STUB_SIZE), \ "i" (&fn)) static __always_inline void |