Re: [PATCH v2 1/3] Consolidate fallocate{64} implementations

[Adhemerval Zanella <adhemerval dot zanella at linaro dot org>]

Hi Siddhesh,

Thanks for the review, comments below:

On 29/09/2016 21:51, Siddhesh Poyarekar wrote:
>> diff --git a/sysdeps/unix/sysv/linux/tst-fallocate-common.c b/sysdeps/unix/sysv/linux/tst-fallocate-common.c
>> new file mode 100644
>> index 0000000..5ef66be
>> --- /dev/null
>> +++ b/sysdeps/unix/sysv/linux/tst-fallocate-common.c

>> +
>> +void
>> +do_prepare (void)
>> +{
>> +  temp_fd = create_temp_file ("tst-fallocate.", &temp_filename);
>> +  if (temp_fd == -1)
>> +    {
>> +      printf ("cannot create temporary file: %m\n");
>> +      exit (1);
>> +    }
>> +}
>> +
>> +#define FAIL(str) \
>> +  do { printf ("error: %s (line %d)\n", str, __LINE__); return 1; } while (0)
> 
> Suggest: Use statement expressions since we use it widely in glibc.  It
> might be a nice low hanging fruit project to fix all our tests to use
> FAIL defined like this.

Ack, I changed to a statement expression.

> 
>> +
>> +static int
>> +do_test_with_offset (off_t offset)
>> +{
>> +  int ret;
>> +  struct stat finfo;
>> +  char bwrite[1024] = { 0xf0 };
>> +  char bread[1024];
> 
> Define a macro BLOCK_SIZE to 1024 and use that everywhere.

Ack.
 
>> +
>> +  /* It tries to fallocate 1024 bytes from 'offset' and then write 1024 bytes.
>> +     After both operation rewind the file descriptor and read 1024 bytes
>> +     and check if both buffer have the same contents.  */
>> +  ret = fallocate (temp_fd, 0, offset, 1024);
>> +  if (ret == -1)
>> +    FAIL ("fallocate failed");
>> +
>> +  ret = fstat (temp_fd, &finfo);
>> +  if (ret == -1)
>> +    FAIL ("fstat failed");
>> +
>> +  if (finfo.st_size < (offset + 1024))
>> +    FAIL ("size of first fallocate less than expected (1024)");
> 
> Suggest: Print offset + 1024 instead of just 1024.

Ack.

>> diff --git a/sysdeps/unix/sysv/linux/tst-fallocate64.c b/sysdeps/unix/sysv/linux/tst-fallocate64.c
>> new file mode 100644
>> index 0000000..78bcb8c
>> --- /dev/null
>> +++ b/sysdeps/unix/sysv/linux/tst-fallocate64.c

>> +
>> +static int
>> +do_test (void)
>> +{
>> +  ssize_t ret;
>> +
>> +  ret = do_test_with_offset (0);
>> +  if (ret == -1)
>> +    return 1;
> 
> This will fail since you return 1 on failure from do_test_with_offset,
> not -1.

Ack, I fixed it.

> 
>> +
>> +  off_t base_offset = UINT32_MAX + 2048LL;
> 
> This will overflow on 32-bit.

Not really since we explicit build the test with _FILE_OFFSET_BITS=64 so
off_t will be 64-bit regardless.

> 
>> +  ret = do_test_with_offset (base_offset);
>> +  if (ret == -1)
>> +    return 1;
> 
> Again do_test_with_offset returns 1, not -1.

Ack.

Below it is a version with the test fixed based on your comments:

--

diff --git a/sysdeps/unix/sysv/linux/Makefile b/sysdeps/unix/sysv/linux/Makefile
index 9a0423e..f8f778b 100644
--- a/sysdeps/unix/sysv/linux/Makefile
+++ b/sysdeps/unix/sysv/linux/Makefile
@@ -42,7 +42,8 @@ sysdep_headers += sys/mount.h sys/acct.h sys/sysctl.h \
 		  bits/socket_type.h bits/syscall.h bits/sysctl.h \
 		  bits/mman-linux.h
 
-tests += tst-clone tst-clone2 tst-fanotify tst-personality tst-quota
+tests += tst-clone tst-clone2 tst-fanotify tst-personality tst-quota \
+	 tst-fallocate tst-fallocate64
 
 # Generate the list of SYS_* macros for the system calls (__NR_* macros).
 
diff --git a/sysdeps/unix/sysv/linux/fallocate.c b/sysdeps/unix/sysv/linux/fallocate.c
index 6a58a5f..a38e9a6 100644
--- a/sysdeps/unix/sysv/linux/fallocate.c
+++ b/sysdeps/unix/sysv/linux/fallocate.c
@@ -19,17 +19,12 @@
 #include <fcntl.h>
 #include <sysdep-cancel.h>
 
-
+#ifndef __OFF_T_MATCHES_OFF64_T
 /* Reserve storage for the data of the file associated with FD.  */
 int
 fallocate (int fd, int mode, __off_t offset, __off_t len)
 {
-#ifdef __NR_fallocate
   return SYSCALL_CANCEL (fallocate, fd, mode,
-			 __LONG_LONG_PAIR (offset >> 31, offset),
-			 __LONG_LONG_PAIR (len >> 31, len));
-#else
-  __set_errno (ENOSYS);
-  return -1;
-#endif
+			 SYSCALL_LL (offset), SYSCALL_LL (len));
 }
+#endif
diff --git a/sysdeps/unix/sysv/linux/fallocate64.c b/sysdeps/unix/sysv/linux/fallocate64.c
index 8e76d6f..d466095 100644
--- a/sysdeps/unix/sysv/linux/fallocate64.c
+++ b/sysdeps/unix/sysv/linux/fallocate64.c
@@ -24,14 +24,10 @@
 int
 fallocate64 (int fd, int mode, __off64_t offset, __off64_t len)
 {
-#ifdef __NR_fallocate
   return SYSCALL_CANCEL (fallocate, fd, mode,
-			 __LONG_LONG_PAIR ((long int) (offset >> 32),
-					   (long int) offset),
-			 __LONG_LONG_PAIR ((long int) (len >> 32),
-					   (long int) len));
-#else
-  __set_errno (ENOSYS);
-  return -1;
-#endif
+			 SYSCALL_LL64 (offset), SYSCALL_LL64 (len));
 }
+
+#ifdef __OFF_T_MATCHES_OFF64_T
+weak_alias (fallocate64, fallocate)
+#endif
diff --git a/sysdeps/unix/sysv/linux/mips/mips64/n32/fallocate.c b/sysdeps/unix/sysv/linux/mips/mips64/n32/fallocate.c
deleted file mode 100644
index 4e432f4..0000000
--- a/sysdeps/unix/sysv/linux/mips/mips64/n32/fallocate.c
+++ /dev/null
@@ -1,33 +0,0 @@
-/* Copyright (C) 2007-2016 Free Software Foundation, Inc.
-   This file is part of the GNU C Library.
-
-   The GNU C Library is free software; you can redistribute it and/or
-   modify it under the terms of the GNU Lesser General Public
-   License as published by the Free Software Foundation; either
-   version 2.1 of the License, or (at your option) any later version.
-
-   The GNU C Library is distributed in the hope that it will be useful,
-   but WITHOUT ANY WARRANTY; without even the implied warranty of
-   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
-   Lesser General Public License for more details.
-
-   You should have received a copy of the GNU Lesser General Public
-   License along with the GNU C Library.  If not, see
-   <http://www.gnu.org/licenses/>.  */
-
-#include <errno.h>
-#include <fcntl.h>
-#include <sysdep-cancel.h>
-
-
-/* Reserve storage for the data of the file associated with FD.  */
-int
-fallocate (int fd, int mode, __off_t offset, __off_t len)
-{
-#ifdef __NR_fallocate
-  return SYSCALL_CANCEL (fallocate, fd, mode, offset, len);
-#else
-  __set_errno (ENOSYS);
-  return -1;
-#endif
-}
diff --git a/sysdeps/unix/sysv/linux/mips/mips64/n32/fallocate64.c b/sysdeps/unix/sysv/linux/mips/mips64/n32/fallocate64.c
deleted file mode 100644
index 95c9eab..0000000
--- a/sysdeps/unix/sysv/linux/mips/mips64/n32/fallocate64.c
+++ /dev/null
@@ -1,33 +0,0 @@
-/* Copyright (C) 2007-2016 Free Software Foundation, Inc.
-   This file is part of the GNU C Library.
-
-   The GNU C Library is free software; you can redistribute it and/or
-   modify it under the terms of the GNU Lesser General Public
-   License as published by the Free Software Foundation; either
-   version 2.1 of the License, or (at your option) any later version.
-
-   The GNU C Library is distributed in the hope that it will be useful,
-   but WITHOUT ANY WARRANTY; without even the implied warranty of
-   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
-   Lesser General Public License for more details.
-
-   You should have received a copy of the GNU Lesser General Public
-   License along with the GNU C Library.  If not, see
-   <http://www.gnu.org/licenses/>.  */
-
-#include <errno.h>
-#include <fcntl.h>
-#include <sysdep-cancel.h>
-
-
-/* Reserve storage for the data of the file associated with FD.  */
-int
-fallocate64 (int fd, int mode, __off64_t offset, __off64_t len)
-{
-#ifdef __NR_fallocate
-  return SYSCALL_CANCEL (fallocate, fd, mode, offset, len);
-#else
-  __set_errno (ENOSYS);
-  return -1;
-#endif
-}
diff --git a/sysdeps/unix/sysv/linux/mips/mips64/n64/fallocate.c b/sysdeps/unix/sysv/linux/mips/mips64/n64/fallocate.c
deleted file mode 100644
index d3b7218..0000000
--- a/sysdeps/unix/sysv/linux/mips/mips64/n64/fallocate.c
+++ /dev/null
@@ -1 +0,0 @@
-#include <sysdeps/unix/sysv/linux/wordsize-64/fallocate.c>
diff --git a/sysdeps/unix/sysv/linux/mips/mips64/n64/fallocate64.c b/sysdeps/unix/sysv/linux/mips/mips64/n64/fallocate64.c
deleted file mode 100644
index fb2b681..0000000
--- a/sysdeps/unix/sysv/linux/mips/mips64/n64/fallocate64.c
+++ /dev/null
@@ -1 +0,0 @@
-/* fallocate64 is in fallocate.c */
diff --git a/sysdeps/unix/sysv/linux/tst-fallocate-common.c b/sysdeps/unix/sysv/linux/tst-fallocate-common.c
new file mode 100644
index 0000000..76f31ff
--- /dev/null
+++ b/sysdeps/unix/sysv/linux/tst-fallocate-common.c
@@ -0,0 +1,98 @@
+/* Basic fallocate test (no specific flags is checked).
+   Copyright (C) 2016 Free Software Foundation, Inc.
+   This file is part of the GNU C Library.
+
+   The GNU C Library is free software; you can redistribute it and/or
+   modify it under the terms of the GNU Lesser General Public
+   License as published by the Free Software Foundation; either
+   version 2.1 of the License, or (at your option) any later version.
+
+   The GNU C Library is distributed in the hope that it will be useful,
+   but WITHOUT ANY WARRANTY; without even the implied warranty of
+   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+   Lesser General Public License for more details.
+
+   You should have received a copy of the GNU Lesser General Public
+   License along with the GNU C Library; if not, see
+   <http://www.gnu.org/licenses/>.  */
+
+#include <fcntl.h>
+#include <sys/types.h>
+#include <sys/stat.h>
+#include <unistd.h>
+
+static void do_prepare (void);
+#define PREPARE(argc, argv)     do_prepare ()
+static int do_test (void);
+#define TEST_FUNCTION           do_test ()
+
+#define TIMEOUT 20 /* sec.  */
+
+#define XSTR(s) STR(S)
+#define STR(s)  #s
+
+#include <test-skeleton.c>
+
+static char *temp_filename;
+static int temp_fd;
+
+void
+do_prepare (void)
+{
+  temp_fd = create_temp_file ("tst-fallocate.", &temp_filename);
+  if (temp_fd == -1)
+    {
+      printf ("cannot create temporary file: %m\n");
+      exit (1);
+    }
+}
+
+#define FAIL(...) \
+  ({ \
+     printf ("error: line %d: ", __LINE__); \
+     printf (__VA_ARGS__); \
+     printf ("\n"); \
+     return 1; \
+  })
+
+static int
+do_test_with_offset (off_t offset)
+{
+  int ret;
+  struct stat finfo;
+#define BLK_SIZE 1024
+  char bwrite[BLK_SIZE] = { 0xf0 };
+  char bread[BLK_SIZE];
+
+  /* It tries to fallocate 1024 bytes from 'offset' and then write 1024 bytes.
+     After both operation rewind the file descriptor and read 1024 bytes
+     and check if both buffer have the same contents.  */
+  ret = fallocate (temp_fd, 0, offset, BLK_SIZE);
+  if (ret == -1)
+    FAIL ("fallocate failed");
+
+  ret = fstat (temp_fd, &finfo);
+  if (ret == -1)
+    FAIL ("fstat failed");
+
+  if (finfo.st_size < (offset + BLK_SIZE))
+    FAIL ("size of first fallocate less than expected (%llu)",
+	  (long long unsigned int)offset + BLK_SIZE);
+
+  if (lseek (temp_fd, offset, SEEK_SET) == (off_t) -1)
+    FAIL ("fseek (0, SEEK_SET) failed");
+
+  if (write (temp_fd, bwrite, BLK_SIZE) != BLK_SIZE)
+    FAIL ("fail trying to write " XSTR (BLK_SIZE) " bytes");
+
+  if (lseek (temp_fd, offset, SEEK_SET) == (off_t) -1)
+    FAIL ("fseek (0, SEEK_SET) failed");
+
+  if (read (temp_fd, bread, BLK_SIZE) != BLK_SIZE)
+    FAIL ("fail trying to read " XSTR (BLK_SIZE) " bytes");
+
+  if (memcmp (bwrite, bread, BLK_SIZE) != 0)
+    FAIL ("buffer writted different than buffer readed");
+
+  return 0;
+}
diff --git a/sysdeps/unix/sysv/linux/tst-fallocate.c b/sysdeps/unix/sysv/linux/tst-fallocate.c
new file mode 100644
index 0000000..ec3867c
--- /dev/null
+++ b/sysdeps/unix/sysv/linux/tst-fallocate.c
@@ -0,0 +1,25 @@
+/* Basic fallocate test (no specific flags is checked).
+   Copyright (C) 2016 Free Software Foundation, Inc.
+   This file is part of the GNU C Library.
+
+   The GNU C Library is free software; you can redistribute it and/or
+   modify it under the terms of the GNU Lesser General Public
+   License as published by the Free Software Foundation; either
+   version 2.1 of the License, or (at your option) any later version.
+
+   The GNU C Library is distributed in the hope that it will be useful,
+   but WITHOUT ANY WARRANTY; without even the implied warranty of
+   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+   Lesser General Public License for more details.
+
+   You should have received a copy of the GNU Lesser General Public
+   License along with the GNU C Library; if not, see
+   <http://www.gnu.org/licenses/>.  */
+
+#include "tst-fallocate-common.c"
+
+static int
+do_test (void)
+{
+  return do_test_with_offset (0);
+}
diff --git a/sysdeps/unix/sysv/linux/tst-fallocate64.c b/sysdeps/unix/sysv/linux/tst-fallocate64.c
new file mode 100644
index 0000000..3c0d370
--- /dev/null
+++ b/sysdeps/unix/sysv/linux/tst-fallocate64.c
@@ -0,0 +1,54 @@
+/* Basic fallocate64 test (no specific flags is checked).
+   Copyright (C) 2016 Free Software Foundation, Inc.
+   This file is part of the GNU C Library.
+
+   The GNU C Library is free software; you can redistribute it and/or
+   modify it under the terms of the GNU Lesser General Public
+   License as published by the Free Software Foundation; either
+   version 2.1 of the License, or (at your option) any later version.
+
+   The GNU C Library is distributed in the hope that it will be useful,
+   but WITHOUT ANY WARRANTY; without even the implied warranty of
+   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+   Lesser General Public License for more details.
+
+   You should have received a copy of the GNU Lesser General Public
+   License along with the GNU C Library; if not, see
+   <http://www.gnu.org/licenses/>.  */
+
+#define _FILE_OFFSET_BITS 64
+#include "tst-fallocate-common.c"
+
+static int
+do_test (void)
+{
+  ssize_t ret;
+
+  ret = do_test_with_offset (0);
+  if (ret == 1)
+    return 1;
+
+  off_t base_offset = UINT32_MAX + 2048LL;
+  ret = do_test_with_offset (base_offset);
+  if (ret == 1)
+    return 1;
+
+  struct stat st;
+  if (fstat (temp_fd, &st) == -1)
+    {
+      printf ("error: fstat on temporary file failed: %m");
+      return 1;
+    }
+
+  /* The file size should >= base_offset plus bytes written.  */
+  off_t expected_value = base_offset + ret;
+  if (st.st_size < expected_value)
+    {
+      printf ("error: file size less than expected (%jd > %jd)\n",
+              (intmax_t) expected_value, (intmax_t) st.st_size);
+      return 1;
+    }
+
+  return 0;
+}
+
diff --git a/sysdeps/unix/sysv/linux/wordsize-64/fallocate.c b/sysdeps/unix/sysv/linux/wordsize-64/fallocate.c
deleted file mode 100644
index c1dd0b4..0000000
--- a/sysdeps/unix/sysv/linux/wordsize-64/fallocate.c
+++ /dev/null
@@ -1,34 +0,0 @@
-/* Copyright (C) 2007-2016 Free Software Foundation, Inc.
-   This file is part of the GNU C Library.
-
-   The GNU C Library is free software; you can redistribute it and/or
-   modify it under the terms of the GNU Lesser General Public
-   License as published by the Free Software Foundation; either
-   version 2.1 of the License, or (at your option) any later version.
-
-   The GNU C Library is distributed in the hope that it will be useful,
-   but WITHOUT ANY WARRANTY; without even the implied warranty of
-   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
-   Lesser General Public License for more details.
-
-   You should have received a copy of the GNU Lesser General Public
-   License along with the GNU C Library; if not, see
-   <http://www.gnu.org/licenses/>.  */
-
-#include <errno.h>
-#include <fcntl.h>
-#include <sysdep-cancel.h>
-
-
-/* Reserve storage for the data of the file associated with FD.  */
-int
-fallocate (int fd, int mode, __off_t offset, __off_t len)
-{
-#ifdef __NR_fallocate
-  return SYSCALL_CANCEL (fallocate, fd, mode, offset, len);
-#else
-  __set_errno (ENOSYS);
-  return -1;
-#endif
-}
-strong_alias (fallocate, fallocate64)
diff --git a/sysdeps/unix/sysv/linux/wordsize-64/fallocate64.c b/sysdeps/unix/sysv/linux/wordsize-64/fallocate64.c
deleted file mode 100644
index df33112..0000000
--- a/sysdeps/unix/sysv/linux/wordsize-64/fallocate64.c
+++ /dev/null
@@ -1 +0,0 @@
-/* fallocate64 is in posix_fallocate.c */