lk/linux-kernel-test
1
0
Fork 0
Code Issues Pull Requests Releases Wiki Activity

[PATCH] v9fs: zero copy implementation

Browse Source 
Performance enhancement reducing the number of copies in the data and
stat paths.

Signed-off-by: Latchesar Ionkov <lucho@ionkov.net>
Cc: Eric Van Hensbergen <ericvh@ericvh.myip.org>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
This commit is contained in:
Latchesar Ionkov
2006-01-08 01:05:00 -08:00
committed by Linus Torvalds
parent d8da097afb
commit 531b1094b7
18 changed files with 1079 additions and 1043 deletions
Download Patch File Download Diff File Expand all files Collapse all files

25
fs/9p/vfs_file.c
View File

@@ -32,6 +32,7 @@
#include <linux/string.h>
#include <linux/smp_lock.h>
#include <linux/inet.h>
#include <linux/version.h>
#include <linux/list.h>
#include <asm/uaccess.h>
#include <linux/idr.h>
@@ -117,9 +118,7 @@ int v9fs_file_open(struct inode *inode, struct file *file)
result = v9fs_t_open(v9ses, newfid, open_mode, &fcall);
if (result < 0) {
dprintk(DEBUG_ERROR,
"open failed, open_mode 0x%x: %s\n", open_mode,
FCALL_ERROR(fcall));
PRINT_FCALL_ERROR("open failed", fcall);
kfree(fcall);
return result;
}
@@ -256,7 +255,6 @@ v9fs_file_write(struct file *filp, const char __user * data,
int result = -EIO;
int rsize = 0;
int total = 0;
char *buf;
dprintk(DEBUG_VFS, "data %p count %d offset %x\n", data, (int)count,
(int)*offset);
@@ -264,28 +262,14 @@ v9fs_file_write(struct file *filp, const char __user * data,
if (v9fid->iounit != 0 && rsize > v9fid->iounit)
rsize = v9fid->iounit;
buf = kmalloc(v9ses->maxdata - V9FS_IOHDRSZ, GFP_KERNEL);
if (!buf)
return -ENOMEM;
do {
if (count < rsize)
rsize = count;
result = copy_from_user(buf, data, rsize);
if (result) {
dprintk(DEBUG_ERROR, "Problem copying from user\n");
kfree(buf);
return -EFAULT;
}
dump_data(buf, rsize);
result = v9fs_t_write(v9ses, fid, *offset, rsize, buf, &fcall);
result = v9fs_t_write(v9ses, fid, *offset, rsize, data, &fcall);
if (result < 0) {
eprintk(KERN_ERR, "error while writing: %s(%d)\n",
FCALL_ERROR(fcall), result);
PRINT_FCALL_ERROR("error while writing", fcall);
kfree(fcall);
kfree(buf);
return result;
} else
*offset += result;
@@ -305,7 +289,6 @@ v9fs_file_write(struct file *filp, const char __user * data,
total += result;
} while (count);
kfree(buf);
return total;
}