diff mbox series

[v7,12/74] linux-user: Split out name_to_handle_at, open_by_handle_at

Message ID 20190519203726.20729-13-richard.henderson@linaro.org (mailing list archive)
State New, archived
Headers show
Series linux-user: Split do_syscall | expand

Commit Message

Richard Henderson May 19, 2019, 8:36 p.m. UTC
All targets have these syscalls, so they need not be ifdefed.
If we provide safe syscalls for the host, we can remove the
configure test for this too.

Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
---
 linux-user/syscall-defs.h     |   3 +
 linux-user/syscall.h          |   1 +
 linux-user/strace.c           |   5 +-
 linux-user/syscall-file.inc.c |  81 +++++++++++++++++++++++++++
 linux-user/syscall.c          | 102 ++--------------------------------
 configure                     |  20 -------
 linux-user/strace.list        |   3 -
 7 files changed, 93 insertions(+), 122 deletions(-)
diff mbox series

Patch

diff --git a/linux-user/syscall-defs.h b/linux-user/syscall-defs.h
index ae89be0e87..1fc89c1b08 100644
--- a/linux-user/syscall-defs.h
+++ b/linux-user/syscall-defs.h
@@ -17,10 +17,13 @@ 
  */
 
 SYSCALL_DEF(close, ARG_DEC);
+SYSCALL_DEF(name_to_handle_at,
+            ARG_ATDIRFD, ARG_STR, ARG_PTR, ARG_PTR, ARG_ATFLAG);
 #ifdef TARGET_NR_open
 SYSCALL_DEF(open, ARG_STR, ARG_OPENFLAG, ARG_MODEFLAG);
 #endif
 SYSCALL_DEF(openat, ARG_ATDIRFD, ARG_STR, ARG_OPENFLAG, ARG_MODEFLAG);
+SYSCALL_DEF(open_by_handle_at, ARG_DEC, ARG_PTR, ARG_OPENFLAG);
 SYSCALL_DEF_FULL(pread64, .impl = impl_pread64,
                  .args = args_pread64_pwrite64,
                  .arg_type = { ARG_DEC, ARG_PTR, ARG_DEC, ARG_DEC64 });
diff --git a/linux-user/syscall.h b/linux-user/syscall.h
index 43b5dc0684..83f602f8e7 100644
--- a/linux-user/syscall.h
+++ b/linux-user/syscall.h
@@ -57,6 +57,7 @@  typedef enum {
 
     /* These print as sets of flags.  */
     ARG_ATDIRFD,
+    ARG_ATFLAG,
     ARG_MODEFLAG,
     ARG_OPENFLAG,
 
diff --git a/linux-user/strace.c b/linux-user/strace.c
index 2f1c7e537f..e92b2c298e 100644
--- a/linux-user/strace.c
+++ b/linux-user/strace.c
@@ -780,7 +780,7 @@  UNUSED static struct flags access_flags[] = {
     FLAG_END,
 };
 
-UNUSED static struct flags at_file_flags[] = {
+static struct flags const at_file_flags[] = {
 #ifdef AT_EACCESS
     FLAG_GENERIC(AT_EACCESS),
 #endif
@@ -2693,6 +2693,9 @@  static void print_syscall_def1(const SyscallDef *def, int64_t args[6])
         case ARG_ATDIRFD:
             len = add_atdirfd(b, rest, arg);
             break;
+        case ARG_ATFLAG:
+            len = add_flags(b, rest, at_file_flags, arg, false);
+            break;
         case ARG_MODEFLAG:
             len = add_flags(b, rest, mode_flags, arg, true);
             break;
diff --git a/linux-user/syscall-file.inc.c b/linux-user/syscall-file.inc.c
index 61cfe2acb7..dd44d5b804 100644
--- a/linux-user/syscall-file.inc.c
+++ b/linux-user/syscall-file.inc.c
@@ -323,6 +323,87 @@  SYSCALL_IMPL(openat)
     return do_openat(cpu_env, arg1, arg2, arg3, arg4);
 }
 
+SYSCALL_IMPL(name_to_handle_at)
+{
+    struct file_handle *target_fh;
+    struct file_handle *fh;
+    int mid = 0;
+    abi_long ret;
+    char *name;
+    uint32_t size, total_size;
+
+    if (get_user_s32(size, arg3)) {
+        return -TARGET_EFAULT;
+    }
+    total_size = sizeof(struct file_handle) + size;
+    target_fh = lock_user(VERIFY_WRITE, arg3, total_size, 0);
+    if (!target_fh) {
+        return -TARGET_EFAULT;
+    }
+
+    name = lock_user_string(arg2);
+    if (!name) {
+        unlock_user(target_fh, arg3, 0);
+        return -TARGET_EFAULT;
+    }
+
+    fh = g_malloc0(total_size);
+    fh->handle_bytes = size;
+
+    ret = get_errno(safe_name_to_handle_at(arg1, path(name), fh, &mid, arg5));
+    unlock_user(name, arg2, 0);
+
+    /*
+     * man name_to_handle_at(2):
+     * Other than the use of the handle_bytes field, the caller should treat
+     * the file_handle structure as an opaque data type
+     */
+    if (!is_error(ret)) {
+        memcpy(target_fh, fh, total_size);
+        target_fh->handle_bytes = tswap32(fh->handle_bytes);
+        target_fh->handle_type = tswap32(fh->handle_type);
+        g_free(fh);
+        unlock_user(target_fh, arg3, total_size);
+
+        if (put_user_s32(mid, arg4)) {
+            return -TARGET_EFAULT;
+        }
+    }
+    return ret;
+}
+
+SYSCALL_IMPL(open_by_handle_at)
+{
+    abi_long mount_fd = arg1;
+    abi_long handle = arg2;
+    int host_flags = target_to_host_bitmask(arg3, fcntl_flags_tbl);
+    struct file_handle *target_fh;
+    struct file_handle *fh;
+    unsigned int size, total_size;
+    abi_long ret;
+
+    if (get_user_s32(size, handle)) {
+        return -TARGET_EFAULT;
+    }
+    total_size = sizeof(struct file_handle) + size;
+    target_fh = lock_user(VERIFY_READ, handle, total_size, 1);
+    if (!target_fh) {
+        return -TARGET_EFAULT;
+    }
+
+    fh = g_memdup(target_fh, total_size);
+    fh->handle_bytes = size;
+    fh->handle_type = tswap32(target_fh->handle_type);
+
+    ret = get_errno(safe_open_by_handle_at(mount_fd, fh, host_flags));
+
+    g_free(fh);
+    unlock_user(target_fh, handle, total_size);
+
+    fd_trans_unregister(ret);
+    return ret;
+}
+
 /*
  * Both pread64 and pwrite64 merge args into a 64-bit offset,
  * but the input registers and ordering are target specific.
diff --git a/linux-user/syscall.c b/linux-user/syscall.c
index 817c4a7296..c49f8aebd2 100644
--- a/linux-user/syscall.c
+++ b/linux-user/syscall.c
@@ -806,6 +806,10 @@  safe_syscall5(int, mq_timedsend, int, mqdes, const char *, msg_ptr,
 safe_syscall5(int, mq_timedreceive, int, mqdes, char *, msg_ptr,
               size_t, len, unsigned *, prio, const struct timespec *, timeout)
 #endif
+safe_syscall5(int, name_to_handle_at, int, dirfd, const char *, pathname,
+              struct file_handle *, handle, int *, mount_id, int, flags)
+safe_syscall3(int, open_by_handle_at, int, mount_fd,
+              struct file_handle *, handle, int, flags)
 /* We do ioctl like this rather than via safe_syscall3 to preserve the
  * "third argument might be integer or pointer or not present" behaviour of
  * the libc function.
@@ -6479,93 +6483,6 @@  static int do_futex(target_ulong uaddr, int op, int val, target_ulong timeout,
         return -TARGET_ENOSYS;
     }
 }
-#if defined(TARGET_NR_name_to_handle_at) && defined(CONFIG_OPEN_BY_HANDLE)
-static abi_long do_name_to_handle_at(abi_long dirfd, abi_long pathname,
-                                     abi_long handle, abi_long mount_id,
-                                     abi_long flags)
-{
-    struct file_handle *target_fh;
-    struct file_handle *fh;
-    int mid = 0;
-    abi_long ret;
-    char *name;
-    unsigned int size, total_size;
-
-    if (get_user_s32(size, handle)) {
-        return -TARGET_EFAULT;
-    }
-
-    name = lock_user_string(pathname);
-    if (!name) {
-        return -TARGET_EFAULT;
-    }
-
-    total_size = sizeof(struct file_handle) + size;
-    target_fh = lock_user(VERIFY_WRITE, handle, total_size, 0);
-    if (!target_fh) {
-        unlock_user(name, pathname, 0);
-        return -TARGET_EFAULT;
-    }
-
-    fh = g_malloc0(total_size);
-    fh->handle_bytes = size;
-
-    ret = get_errno(name_to_handle_at(dirfd, path(name), fh, &mid, flags));
-    unlock_user(name, pathname, 0);
-
-    /* man name_to_handle_at(2):
-     * Other than the use of the handle_bytes field, the caller should treat
-     * the file_handle structure as an opaque data type
-     */
-
-    memcpy(target_fh, fh, total_size);
-    target_fh->handle_bytes = tswap32(fh->handle_bytes);
-    target_fh->handle_type = tswap32(fh->handle_type);
-    g_free(fh);
-    unlock_user(target_fh, handle, total_size);
-
-    if (put_user_s32(mid, mount_id)) {
-        return -TARGET_EFAULT;
-    }
-
-    return ret;
-
-}
-#endif
-
-#if defined(TARGET_NR_open_by_handle_at) && defined(CONFIG_OPEN_BY_HANDLE)
-static abi_long do_open_by_handle_at(abi_long mount_fd, abi_long handle,
-                                     abi_long flags)
-{
-    struct file_handle *target_fh;
-    struct file_handle *fh;
-    unsigned int size, total_size;
-    abi_long ret;
-
-    if (get_user_s32(size, handle)) {
-        return -TARGET_EFAULT;
-    }
-
-    total_size = sizeof(struct file_handle) + size;
-    target_fh = lock_user(VERIFY_READ, handle, total_size, 1);
-    if (!target_fh) {
-        return -TARGET_EFAULT;
-    }
-
-    fh = g_memdup(target_fh, total_size);
-    fh->handle_bytes = size;
-    fh->handle_type = tswap32(target_fh->handle_type);
-
-    ret = get_errno(open_by_handle_at(mount_fd, fh,
-                    target_to_host_bitmask(flags, fcntl_flags_tbl)));
-
-    g_free(fh);
-
-    unlock_user(target_fh, handle, total_size);
-
-    return ret;
-}
-#endif
 
 #if defined(TARGET_NR_signalfd) || defined(TARGET_NR_signalfd4)
 
@@ -6761,17 +6678,6 @@  static abi_long do_syscall1(void *cpu_env, int num, abi_long arg1,
         preexit_cleanup(cpu_env, arg1);
         _exit(arg1);
         return 0; /* avoid warning */
-#if defined(TARGET_NR_name_to_handle_at) && defined(CONFIG_OPEN_BY_HANDLE)
-    case TARGET_NR_name_to_handle_at:
-        ret = do_name_to_handle_at(arg1, arg2, arg3, arg4, arg5);
-        return ret;
-#endif
-#if defined(TARGET_NR_open_by_handle_at) && defined(CONFIG_OPEN_BY_HANDLE)
-    case TARGET_NR_open_by_handle_at:
-        ret = do_open_by_handle_at(arg1, arg2, arg3);
-        fd_trans_unregister(ret);
-        return ret;
-#endif
     case TARGET_NR_brk:
         return do_brk(arg1);
 #ifdef TARGET_NR_fork
diff --git a/configure b/configure
index d2fc346302..6573fcefcb 100755
--- a/configure
+++ b/configure
@@ -5243,22 +5243,6 @@  if test "$debug_stack_usage" = "yes"; then
 fi
 
 
-##########################################
-# check if we have open_by_handle_at
-
-open_by_handle_at=no
-cat > $TMPC << EOF
-#include <fcntl.h>
-#if !defined(AT_EMPTY_PATH)
-# error missing definition
-#else
-int main(void) { struct file_handle fh; return open_by_handle_at(0, &fh, 0); }
-#endif
-EOF
-if compile_prog "" "" ; then
-    open_by_handle_at=yes
-fi
-
 ########################################
 # check if we have linux/magic.h
 
@@ -7012,10 +6996,6 @@  if test "$crypto_afalg" = "yes" ; then
   echo "CONFIG_AF_ALG=y" >> $config_host_mak
 fi
 
-if test "$open_by_handle_at" = "yes" ; then
-  echo "CONFIG_OPEN_BY_HANDLE=y" >> $config_host_mak
-fi
-
 if test "$linux_magic_h" = "yes" ; then
   echo "CONFIG_LINUX_MAGIC_H=y" >> $config_host_mak
 fi
diff --git a/linux-user/strace.list b/linux-user/strace.list
index f326613934..bf239cb9a3 100644
--- a/linux-user/strace.list
+++ b/linux-user/strace.list
@@ -635,9 +635,6 @@ 
 #ifdef TARGET_NR_munmap
 { TARGET_NR_munmap, "munmap" , NULL, print_munmap, NULL },
 #endif
-#ifdef TARGET_NR_name_to_handle_at
-{ TARGET_NR_name_to_handle_at, "name_to_handle_at" , NULL, NULL, NULL },
-#endif
 #ifdef TARGET_NR_nanosleep
 { TARGET_NR_nanosleep, "nanosleep" , NULL, NULL, NULL },
 #endif