Re: [PATCH] user: Extract common MMAP API to 'user/mmap.h'

[Warner Losh <imp@bsdimp.com>]

[-- Attachment #1: Type: text/plain, Size: 5006 bytes --]

On Fri, Jan 17, 2025 at 10:13 AM Philippe Mathieu-Daudé <philmd@linaro.org>
wrote:

> Keep common MMAP-related declarations in a single place.
>
> Note, this disable ThreadSafetyAnalysis on Linux for:
> - mmap_fork_start()
> - mmap_fork_end().
>
> Signed-off-by: Philippe Mathieu-Daudé <philmd@linaro.org>
> ---
>  bsd-user/qemu.h        | 12 +-----------
>  include/user/mmap.h    | 33 +++++++++++++++++++++++++++++++++
>  linux-user/user-mmap.h | 19 ++-----------------
>  3 files changed, 36 insertions(+), 28 deletions(-)
>  create mode 100644 include/user/mmap.h
>

Reviewed-by: Warner Losh <imp@bsdimp.com>

There's actually rather a lot of things like this since the code lineages
are rather
common and co-evolved between bsd-user and linux-user.

Warner


> diff --git a/bsd-user/qemu.h b/bsd-user/qemu.h
> index 3eaa14f3f56..a451d80a4db 100644
> --- a/bsd-user/qemu.h
> +++ b/bsd-user/qemu.h
> @@ -32,6 +32,7 @@
>  extern char **environ;
>
>  #include "user/thunk.h"
> +#include "user/mmap.h"
>  #include "target_arch.h"
>  #include "syscall_defs.h"
>  #include "target_syscall.h"
> @@ -234,19 +235,8 @@ void print_taken_signal(int target_signum, const
> target_siginfo_t *tinfo);
>  extern int do_strace;
>
>  /* mmap.c */
> -int target_mprotect(abi_ulong start, abi_ulong len, int prot);
> -abi_long target_mmap(abi_ulong start, abi_ulong len, int prot,
> -                     int flags, int fd, off_t offset);
> -int target_munmap(abi_ulong start, abi_ulong len);
> -abi_long target_mremap(abi_ulong old_addr, abi_ulong old_size,
> -                       abi_ulong new_size, unsigned long flags,
> -                       abi_ulong new_addr);
>  int target_msync(abi_ulong start, abi_ulong len, int flags);
> -extern abi_ulong mmap_next_start;
> -abi_ulong mmap_find_vma(abi_ulong start, abi_ulong size);
>  void mmap_reserve(abi_ulong start, abi_ulong size);
> -void TSA_NO_TSA mmap_fork_start(void);
> -void TSA_NO_TSA mmap_fork_end(int child);
>
>  /* main.c */
>  extern char qemu_proc_pathname[];
> diff --git a/include/user/mmap.h b/include/user/mmap.h
> new file mode 100644
> index 00000000000..93476a159d0
> --- /dev/null
> +++ b/include/user/mmap.h
> @@ -0,0 +1,33 @@
> +/*
> + * MMAP declarations for QEMU user emulation
> + *
> + * SPDX-License-Identifier: GPL-2.0-or-later
> + */
> +#ifndef USER_MMAP_H
> +#define USER_MMAP_H
> +
> +#include "qemu/clang-tsa.h"
> +#include "exec/user/abitypes.h"
> +
> +/*
> + * mmap_next_start: The base address for the next mmap without hint,
> + * increased after each successful map, starting at task_unmapped_base.
> + * This is an optimization within QEMU and not part of ADDR_COMPAT_LAYOUT.
> + */
> +extern abi_ulong mmap_next_start;
> +
> +int target_mprotect(abi_ulong start, abi_ulong len, int prot);
> +
> +abi_long target_mmap(abi_ulong start, abi_ulong len, int prot,
> +                     int flags, int fd, off_t offset);
> +int target_munmap(abi_ulong start, abi_ulong len);
> +abi_long target_mremap(abi_ulong old_addr, abi_ulong old_size,
> +                       abi_ulong new_size, unsigned long flags,
> +                       abi_ulong new_addr);
> +
> +abi_ulong mmap_find_vma(abi_ulong, abi_ulong, abi_ulong);
> +
> +void TSA_NO_TSA mmap_fork_start(void);
> +void TSA_NO_TSA mmap_fork_end(int child);
> +
> +#endif
> diff --git a/linux-user/user-mmap.h b/linux-user/user-mmap.h
> index b94bcdcf83c..dfc4477a720 100644
> --- a/linux-user/user-mmap.h
> +++ b/linux-user/user-mmap.h
> @@ -18,6 +18,8 @@
>  #ifndef LINUX_USER_USER_MMAP_H
>  #define LINUX_USER_USER_MMAP_H
>
> +#include "user/mmap.h"
> +
>  /*
>   * Guest parameters for the ADDR_COMPAT_LAYOUT personality
>   * (at present this is the only layout supported by QEMU).
> @@ -39,24 +41,7 @@
>  extern abi_ulong task_unmapped_base;
>  extern abi_ulong elf_et_dyn_base;
>
> -/*
> - * mmap_next_start: The base address for the next mmap without hint,
> - * increased after each successful map, starting at task_unmapped_base.
> - * This is an optimization within QEMU and not part of ADDR_COMPAT_LAYOUT.
> - */
> -extern abi_ulong mmap_next_start;
> -
> -int target_mprotect(abi_ulong start, abi_ulong len, int prot);
> -abi_long target_mmap(abi_ulong start, abi_ulong len, int prot,
> -                     int flags, int fd, off_t offset);
> -int target_munmap(abi_ulong start, abi_ulong len);
> -abi_long target_mremap(abi_ulong old_addr, abi_ulong old_size,
> -                       abi_ulong new_size, unsigned long flags,
> -                       abi_ulong new_addr);
>  abi_long target_madvise(abi_ulong start, abi_ulong len_in, int advice);
> -abi_ulong mmap_find_vma(abi_ulong, abi_ulong, abi_ulong);
> -void mmap_fork_start(void);
> -void mmap_fork_end(int child);
>
>  abi_ulong target_shmat(CPUArchState *cpu_env, int shmid,
>                         abi_ulong shmaddr, int shmflg);
> --
> 2.47.1
>
>

[-- Attachment #2: Type: text/html, Size: 6132 bytes --]