Attachment 5312 Details for Bug 6942 – Patch relative to 3-4-test cherry-pick 1

[patch] Patch relative to 3-4-test cherry-pick 1

0001-s3-prefer-posix_fallocate-for-doing-strict-allocat.patch (text/plain), 5.42 KB, created by Olaf Flebbe on 2010-02-10 04:18:46 UTC

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Creator: Olaf Flebbe

Created: 2010-02-10 04:18:46 UTC

Size: 5.42 KB

patch

obsolete

>From 1ce39d37f86704f747ae8bfaf1fa31f5d0861c20 Mon Sep 17 00:00:00 2001
>From: =?utf-8?q?Bj=C3=B6rn=20Jacke?= <bj@sernet.de>
>Date: Wed, 2 Dec 2009 15:13:37 +0100
>Subject: [PATCH] s3: prefer posix_fallocate for doing "strict allocate"
>
>posix_fallocate is more efficient than manual zero'ing the file. When
>preallocation in kernel space is supported it's extremely fast. Support for
>preallocation at fs layer via posix_fallocate and fallocate at kernel site
>can be found in Linux kernel 2.6.23/glibc 2.10 with ext4, XFS and OCFS2. Other
>systems that I know of which support fast preallocation in kernel space are
>AIX 6.1 with JFS2 and recent Solaris versions with ZFS maybe UFS2, too.
>
>People who have a system with preallocation in kernel space might want to set
>"strict allocate = yes". This reduces file fragentation and it's also safer for
>setups with quota being turned on.
>
>As of today most systems still don't have preallocation in kernel space, and
>that's why "strict allocate = no" will stay the default for now.
>
>cherry picked from commit: a1991b17cdb38b1bffa32d2386132ae01f827cd0
>---
> source3/configure.in          |    2 +-
> source3/include/proto.h       |    1 +
> source3/lib/system.c          |   14 ++++++++++++++
> source3/modules/vfs_default.c |   25 +++++++++++++++++++++----
> 4 files changed, 37 insertions(+), 5 deletions(-)
>
>diff --git a/source3/configure.in b/source3/configure.in
>index be18c24..c5569da 100644
>--- a/source3/configure.in
>+++ b/source3/configure.in
>@@ -1042,7 +1042,7 @@ AC_CHECK_FUNCS(setsid glob strpbrk crypt16 getauthuid)
> AC_CHECK_FUNCS(sigprocmask sigblock sigaction sigset innetgr setnetgrent getnetgrent endnetgrent)
> AC_CHECK_FUNCS(initgroups select poll rdchk getgrnam getgrent pathconf)
> AC_CHECK_FUNCS(setpriv setgidx setuidx setgroups sysconf stat64 fstat64)
>-AC_CHECK_FUNCS(lstat64 fopen64 atexit grantpt lseek64 ftruncate64)
>+AC_CHECK_FUNCS(lstat64 fopen64 atexit grantpt lseek64 ftruncate64 posix_fallocate posix_fallocate64)
> AC_CHECK_FUNCS(fseek64 fseeko64 ftell64 ftello64 setluid getpwanam)
> AC_CHECK_FUNCS(opendir64 readdir64 seekdir64 telldir64 rewinddir64 closedir64)
> AC_CHECK_FUNCS(getpwent_r)
>diff --git a/source3/include/proto.h b/source3/include/proto.h
>index d2ae62c..f3c92a8 100644
>--- a/source3/include/proto.h
>+++ b/source3/include/proto.h
>@@ -919,6 +919,7 @@ int sys_stat(const char *fname,SMB_STRUCT_STAT *sbuf);
> int sys_fstat(int fd,SMB_STRUCT_STAT *sbuf);
> int sys_lstat(const char *fname,SMB_STRUCT_STAT *sbuf);
> int sys_ftruncate(int fd, SMB_OFF_T offset);
>+int sys_posix_fallocate(int fd, SMB_OFF_T offset, SMB_OFF_T len);
> SMB_OFF_T sys_lseek(int fd, SMB_OFF_T offset, int whence);
> int sys_fseek(FILE *fp, SMB_OFF_T offset, int whence);
> SMB_OFF_T sys_ftell(FILE *fp);
>diff --git a/source3/lib/system.c b/source3/lib/system.c
>index 6349af5..915d7ca 100644
>--- a/source3/lib/system.c
>+++ b/source3/lib/system.c
>@@ -342,6 +342,20 @@ int sys_lstat(const char *fname,SMB_STRUCT_STAT *sbuf)
> }
> 
> /*******************************************************************
>+ An posix_fallocate() wrapper that will deal with 64 bit filesizes.
>+********************************************************************/
>+#if defined(HAVE_POSIX_FALLOCATE64) || defined(HAVE_POSIX_FALLOCATE)
>+int sys_posix_fallocate(int fd, SMB_OFF_T offset, SMB_OFF_T len)
>+{
>+#if defined(HAVE_EXPLICIT_LARGEFILE_SUPPORT) && defined(HAVE_OFF64_T) && defined(HAVE_POSIX_FALLOCATE64)
>+	return posix_fallocate64(fd, offset, len);
>+#else
>+	return posix_fallocate(fd, offset, len);
>+#endif
>+}
>+#endif
>+
>+/*******************************************************************
>  An ftruncate() wrapper that will deal with 64 bit filesizes.
> ********************************************************************/
> 
>diff --git a/source3/modules/vfs_default.c b/source3/modules/vfs_default.c
>index f5cee4c..4c14e08 100644
>--- a/source3/modules/vfs_default.c
>+++ b/source3/modules/vfs_default.c
>@@ -825,8 +825,6 @@ static int strict_allocate_ftruncate(vfs_handle_struct *handle, files_struct *fs
> 	if (SMB_VFS_FSTAT(fsp, &st) == -1)
> 		return -1;
> 
>-	space_to_write = len - st.st_size;
>-
> #ifdef S_ISFIFO
> 	if (S_ISFIFO(st.st_mode))
> 		return 0;
>@@ -839,7 +837,28 @@ static int strict_allocate_ftruncate(vfs_handle_struct *handle, files_struct *fs
> 	if (st.st_size > len)
> 		return sys_ftruncate(fsp->fh->fd, len);
> 
>+	/* for allocation try posix_fallocate first. This can fail on some
>+	   platforms e.g. when the filesystem doesn't support it and no
>+	   emulation is being done by the libc (like on AIX with JFS1). In that
>+	   case we do our own emulation. posix_fallocate implementations can
>+	   return ENOTSUP or EINVAL in cases like that. */
>+#if defined(HAVE_POSIX_FALLOCATE)
>+	{
>+		int ret = sys_posix_fallocate(fsp->fh->fd, 0, len);
>+		if (ret == ENOSPC) {
>+			errno = ENOSPC;
>+			return -1;
>+		}
>+		if (ret == 0) {
>+			return 0;
>+		}
>+		DEBUG(10,("strict_allocate_ftruncate: sys_posix_fallocate "
>+			"failed with error %d. "
>+			"Falling back to slow manual allocation\n", ret));
>+	}
>+#endif
> 	/* available disk space is enough or not? */
>+	space_to_write = len - st.st_size;
> 	if (lp_strict_allocate(SNUM(fsp->conn))){
> 		uint64_t space_avail;
> 		uint64_t bsize,dfree,dsize;
>@@ -857,8 +876,6 @@ static int strict_allocate_ftruncate(vfs_handle_struct *handle, files_struct *fs
> 	if (SMB_VFS_LSEEK(fsp, st.st_size, SEEK_SET) != st.st_size)
> 		return -1;
> 
>-	space_to_write = len - st.st_size;
>-
> 	memset(zero_space, '\0', sizeof(zero_space));
> 	while ( space_to_write > 0) {
> 		SMB_OFF_T retlen;
>-- 
>1.6.0.2
>

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