Import 2.1.108pre1

Documentation/filesystems/vfs.txt

-A Brief Overview of the Virtual File System
-===========================================
-	by Benjamin LaHaise (blah@dot.superaje.com)
-
-No one else seems to be writing this, so here's a quick description of what
-I've learned while writing lofs.
-
-The VFS is relatively simple, but it is nice not to have to browse through
-pages of code to determine what is expected when writing a filesystem.
-This document is meant to help anyone attempting such a feat, and to clarify 
-a few important points and dependencies.
-
-register_filesystem (struct file_system_type *fstype)
-=====================================================
-
-All filesystems are created equal, or at least they start out that way.
-A filesystem, whether in module form or linked into the kernel, needs to add
-itself to the table of filesystems by calling register_filesystem with an
-initialized file_system_type structure.  Any further functions of the
-filesystem are accessed through the following function tables:
-
-
-struct file_system_type
-=======================
-
-	struct super_block *(*read_super) (struct super_block *sb, void *options, int silent);
-
-		This is the entry point of all filesystems.  If the filesystem succeeds
-		in mounting itself, sb should be returned, otherwise NULL.  options is
-		a pointer to a maximum of PAGE_SIZE-1 bytes of options, typically a zero
-		terminated string passed from mount.  This page is freed after read_super
-		returns, so do not use any pointers into it.
-
-		This routine _must_ set the s_op member of sb to point to a valid
-		super_operations structure.
-
-	const char *name;
-
-		Name points to a string that the system will know the filesystem by.
-
-	int requires_dev;
-
-		Set this flag to 1 if the filesystem requires a block device to be mounted
-		on.
-
-	struct file_system_type * next;
-
-		This field points to the next file_system_type that is present in the system,
-		and should be initialized to NULL.
-
-struct super_operations
-=======================
-
-The super_operations structure is found through the s_op member of the
-super_block structure.
-
-	void (*read_inode) (struct inode *inode);
-	[optional - doesn't quite make sense]
-		read_inode is called by the VFS when iget is called requesting an inode
-		not already present in the inode table.  i_ino is set to the number of the
-		inode requested.
-
-		The i_op member of inode should be set to a valid inode_operations
-		structure.  Typically filesystems have separate inode_operations for
-		directories, files and symlinks.  i_op can be NULL.
-
-	int (*notify_change) (struct inode *, struct iattr *);
-	[optional]
-	void (*write_inode) (struct inode *);
-	[optional]
-
-	int (*put_inode) (struct inode *inode);
-	[optional]
-		put_inode is called by the VFS when the last instance of inode is released
-		with a call to iput.  The only special consideration that should be made
-		is that iget may reuse inode without calling read_inode unless clear_inode
-		is called.  put_inode MUST return 1 if it called clear_inode on the inode,
-		otherwise zero.
-
-	void (*put_super) (struct super_block *);
-	[optional]
-	void (*write_super) (struct super_block *);
-	[optional]
-	void (*statfs) (struct super_block *, struct statfs *, int);
-	[optional]
-	int (*remount_fs) (struct super_block *, int *, char *);
-	[optional]
-
-
-struct inode_operations
-=======================
-
-	struct file_operations * default_file_ops;
-	[mandatory]
-		All inode_operations structures must have default_file_ops pointing to
-		a valid file_operations structure.
-
-	int (*create) (struct inode *,const char *,int,int,struct inode **);
-	[optional]
-
-	int (*lookup) (struct inode *dir, const char *name, int len, struct inode **result);
-	[optional]
-		lookup is called when the VFS wishes to have the filesystem resolve a name
-		into an inode.  Dir is a directory on the filesystem that--we hope--contains
-		the zero-terminated string name (length len).  A return value of zero indicates
-		that there is a valid inode stored in *result.
-
-***		Note: lofs assumes that any filesystem returns an inode within the filesystem
-		for all directory inodes.  Therefore, __iget(sb,ino,0) should be used to fetch
-		the inode in a filesystem's lookup routine.
-
-	int (*link) (struct inode *,struct inode *,const char *,int);
-	[optional]
-	int (*unlink) (struct inode *,const char *,int);
-	[optional]
-	int (*symlink) (struct inode *,const char *,int,const char *);
-	[optional]
-	int (*mkdir) (struct inode *,const char *,int,int);
-	[optional]
-	int (*rmdir) (struct inode *,const char *,int);
-	[optional]
-	int (*mknod) (struct inode *,const char *,int,int,int);
-	[optional]
-	int (*rename) (struct inode *,const char *,int,struct inode *,const char *,int, int);
-	[optional]
-
-	int (*readlink) (struct inode *inode, char *buf, int len);
-	[optional]
-		readlink is called by the VFS to read the contents of a symbolic link.
-		inode is an inode that meets the S_ISLNK test, and buf points to a buffer
-		of len bytes.
-
-	int (*follow_link) (struct inode *,struct inode *,int,int,struct inode **);
-	[optional]
-		follow_link must be implemented if readlink is implemented.
-		Note that follow_link can return a different inode than a
-		lookup_dentry() on the result of readlink() would return.
-		The proc filesystem, in particular, uses this feature heavily.
-		For most user filesystems, however, follow_link() and readlink()
-		should return consistent results.
-
-	int (*readpage) (struct inode *, struct page *);	[optional]
-	int (*writepage) (struct inode *, struct page *);	[mandatory with readpage]
-
-		In order for files to be mmap'd, readpage and writepage are required.
-		A filesystem can use generic_readpage/writepage if it supports the bmap
-		function.  Otherwise, a custom version must be written. 
-
-	int (*bmap) (struct inode *,int);
-	[optional]
-	void (*truncate) (struct inode *);
-	[optional]
-	int (*permission) (struct inode *, int);
-	[optional]
-	int (*smap) (struct inode *,int);
-	[optional]
-
-struct file_operations
-======================
-
-	int (*lseek) (struct inode *, struct file *, off_t, int);
-	int (*read) (struct inode *, struct file *, char *, int);
-	int (*write) (struct inode *, struct file *, const char *, int);
-	int (*readdir) (struct inode *, struct file *, void *, filldir_t);
-	unsigned int (*poll) (struct file *, poll_table *);
-	int (*ioctl) (struct inode *, struct file *, unsigned int, unsigned long);
-	int (*mmap) (struct inode *, struct file *, struct vm_area_struct *);
-	int (*open) (struct inode *, struct file *);
-	void (*release) (struct inode *, struct file *);
-	int (*fsync) (struct inode *, struct file *);
-	int (*fasync) (struct inode *, struct file *, int);
-	int (*check_media_change) (kdev_t dev);
-	int (*revalidate) (kdev_t dev);
-

Makefile

 VERSION = 2
 PATCHLEVEL = 1
-SUBLEVEL = 107
+SUBLEVEL = 108
 
 ARCH := $(shell uname -m | sed -e s/i.86/i386/ -e s/sun4u/sparc64/ -e s/arm.*/arm/ -e s/sa110/arm/)
 

arch/i386/kernel/entry.S

@@ -547,7 +547,8 @@ ENTRY(sys_call_table)
 	.long SYMBOL_NAME(sys_capget)
 	.long SYMBOL_NAME(sys_capset)           /* 185 */
 	.long SYMBOL_NAME(sys_sigaltstack)
+	.long SYMBOL_NAME(sys_sendfile)
 	
-	.rept NR_syscalls-186
+	.rept NR_syscalls-187
 		.long SYMBOL_NAME(sys_ni_syscall)
 	.endr

arch/i386/kernel/setup.c

@@ -466,7 +466,7 @@ int get_cpuinfo(char * buffer)
 			continue;
 #endif
 		p += sprintf(p, "processor\t: %d\n"
-			       "CPU family\t: %c\n"
+			       "cpu family\t: %c\n"
 			       "model\t\t: %s\n"
 			       "vendor_id\t: %s\n",
 			       n,
@@ -512,9 +512,9 @@ int get_cpuinfo(char * buffer)
 			        "hlt_bug\t\t: %s\n"
 			        "sep_bug\t\t: %s\n"
 			        "f00f_bug\t: %s\n"
-			        "FPU\t\t: %s\n"
-			        "FPU_exception\t: %s\n"
-			        "CPUID level\t: %d\n"
+			        "fpu\t\t: %s\n"
+			        "fpu_exception\t: %s\n"
+			        "cpuid level\t: %d\n"
 			        "wp\t\t: %s\n"
 			        "flags\t\t:",
 			     c->fdiv_bug ? "yes" : "no",

arch/m68k/hp300/ints.c

@@ -8,7 +8,6 @@
  *  moment everything difficult is handled by the generic code.
  */
 
-#include <linux/config.h>
 #include <asm/ptrace.h>
 #include <linux/types.h>
 #include <linux/init.h>

arch/m68k/hp300/time.c

@@ -6,7 +6,6 @@
  *  This file contains the HP300-specific time handling code.
  */
 
-#include <linux/config.h>
 #include <asm/ptrace.h>
 #include <linux/types.h>
 #include <linux/init.h>

arch/m68k/kernel/m68k_ksyms.c

-#include <linux/config.h>
 #include <linux/module.h>
 #include <linux/linkage.h>
 #include <linux/sched.h>

arch/m68k/mac/macints.c

@@ -69,6 +69,7 @@
  * - 
  */
 
+#include <linux/config.h>
 #include <linux/types.h>
 #include <linux/kernel.h>
 #include <linux/sched.h>

arch/m68k/mac/via6522.c

@@ -5,7 +5,6 @@
  *	via them as are assorted bits and bobs - eg rtc, adb.
  */
 
-#include <linux/config.h>
 #include <linux/types.h>
 #include <linux/kernel.h>
 #include <linux/mm.h>

arch/ppc/chrp_defconfig

@@ -21,7 +21,7 @@ CONFIG_MACH_SPECIFIC=y
 CONFIG_EXPERIMENTAL=y
 CONFIG_MODULES=y
 # CONFIG_MODVERSIONS is not set
-CONFIG_KERNELD=y
+CONFIG_KMOD=y
 CONFIG_PCI=y
 CONFIG_PCI_OLD_PROC=y
 CONFIG_NET=y

arch/ppc/common_defconfig

@@ -20,7 +20,7 @@ CONFIG_ALL_PPC=y
 CONFIG_EXPERIMENTAL=y
 CONFIG_MODULES=y
 CONFIG_MODVERSIONS=y
-CONFIG_KERNELD=y
+CONFIG_KMOD=y
 CONFIG_PCI=y
 CONFIG_PCI_OLD_PROC=y
 CONFIG_NET=y

arch/ppc/prep_defconfig

@@ -21,7 +21,7 @@ CONFIG_MACH_SPECIFIC=y
 CONFIG_EXPERIMENTAL=y
 CONFIG_MODULES=y
 CONFIG_MODVERSIONS=y
-CONFIG_KERNELD=y
+CONFIG_KMOD=y
 CONFIG_PCI=y
 # CONFIG_PCI_OPTIMIZE is not set
 CONFIG_PCI_OLD_PROC=y

drivers/char/conmakehash.c

@@ -52,7 +52,6 @@ int unicount[MAX_FONTLEN];
 void addpair(int fp, int un)
 {
   int i;
-  unicode hu;
 
   if ( un <= 0xfffe )
     {

drivers/char/fbmem.c

@@ -23,8 +23,8 @@
 #ifdef CONFIG_PROC_FS
 #include <linux/proc_fs.h>
 #endif
-#ifdef CONFIG_KERNELD
-#include <linux/kerneld.h>
+#ifdef CONFIG_KMOD
+#include <linux/kmod.h>
 #endif
 
 #ifdef __mc68000__
@@ -262,7 +262,7 @@ static void set_con2fb_map(int unit, int newidx)
     }
 }
 
-#ifdef CONFIG_KERNELD
+#ifdef CONFIG_KMOD
 static void try_to_load(int fb)
 {
 	char modname[16];
@@ -337,7 +337,7 @@ fb_ioctl(struct inode *inode, struct file *file, unsigned int cmd,
 		    return -EINVAL;
 		if (con2fb.framebuffer < 0 || con2fb.framebuffer >= FB_MAX)
 		    return -EINVAL;
-#ifdef CONFIG_KERNELD
+#ifdef CONFIG_KMOD
 		if (!registered_fb[con2fb.framebuffer])
 		    try_to_load(con2fb.framebuffer);
 #endif
@@ -419,7 +419,7 @@ fb_open(struct inode *inode, struct file *file)
 	int fbidx = GET_FB_IDX(inode->i_rdev);
 	struct fb_info *info;
 
-#ifdef CONFIG_KERNELD
+#ifdef CONFIG_KMOD
 	if (!(info = registered_fb[fbidx]))
 		try_to_load(fbidx);
 #endif

drivers/char/vc_screen.c

@@ -20,8 +20,6 @@
  *	 - making it shorter - scr_readw are macros which expand in PRETTY long code
  */
 
-#include <linux/config.h>
-
 #include <linux/kernel.h>
 #include <linux/major.h>
 #include <linux/errno.h>

drivers/macintosh/chips.c

@@ -8,7 +8,6 @@
  * as published by the Free Software Foundation; either version
  * 2 of the License, or (at your option) any later version.
  */
-#include <linux/config.h>
 #include <linux/kernel.h>
 #include <linux/sched.h>
 #include <linux/delay.h>

drivers/net/7990.c

@@ -12,9 +12,7 @@
  * most of a2025 and sunlance with the aim of merging them, so the 
  * common code was pretty obvious.
  */
-#include <linux/config.h>
 #include <linux/module.h>
-
 #include <linux/kernel.h>
 #include <linux/sched.h>
 #include <linux/types.h>

drivers/net/hamradio/baycom_epp.c

@@ -35,6 +35,7 @@
 
 /*****************************************************************************/
 
+#include <linux/config.h>
 #include <linux/module.h>
 #include <linux/kernel.h>
 #include <linux/types.h>

drivers/net/hamradio/soundmodem/gentbl.c

@@ -438,7 +438,7 @@ static void gentbl_hapn4800(FILE *f)
 {
         int i, j, k, l;
 	float s;
-	float c[40];
+	float c[44];
 	float min, max;
 
 	fprintf(f, "\n/*\n * hapn4800 specific tables\n */\n\n");

drivers/net/hplance.c

@@ -5,9 +5,7 @@
  * Uses the generic 7990.c LANCE code.
  */
 
-#include <linux/config.h>
 #include <linux/module.h>
-
 #include <linux/kernel.h>
 #include <linux/sched.h>
 #include <linux/types.h>

drivers/net/sktr.c

@@ -42,7 +42,6 @@
 
 static const char *version = "sktr.c: v1.01 08/29/97 by Christoph Goos\n";
 
-#include <linux/config.h>
 #ifdef MODULE
 #include <linux/module.h>
 #include <linux/version.h>

drivers/scsi/NCR53C9x.h

@@ -11,6 +11,8 @@
 #ifndef NCR53C9X_H
 #define NCR53C9X_H
 
+#include <linux/config.h>
+
 /* Macros for debugging messages */
 
 /* #define DEBUG_ESP */

drivers/scsi/pluto.c

@@ -14,8 +14,8 @@
 #include <linux/stat.h>
 #include <linux/init.h>
 #include <linux/config.h>
-#ifdef CONFIG_KERNELD
-#include <linux/kerneld.h>
+#ifdef CONFIG_KMOD
+#include <linux/kmod.h>
 #endif
 
 #include <asm/irq.h>
@@ -104,7 +104,7 @@ __initfunc(int pluto_detect(Scsi_Host_Template *tpnt))
 		fcscount++;
 	PLND(("%d channels online\n", fcscount))
 	if (!fcscount) {
-#if defined(MODULE) && defined(CONFIG_FC4_SOC_MODULE) && defined(CONFIG_KERNELD)
+#if defined(MODULE) && defined(CONFIG_FC4_SOC_MODULE) && defined(CONFIG_KMOD)
 		request_module("soc");
 		
 		for_each_online_fc_channel(fc)

drivers/sound/msnd.c

@@ -24,7 +24,6 @@
  *
  ********************************************************************/
 
-#include <linux/config.h>
 #include <linux/module.h>
 #include <linux/kernel.h>
 #include <linux/malloc.h>

drivers/sound/msnd_classic.c

@@ -24,7 +24,6 @@
  *
  ********************************************************************/
 
-#include <linux/config.h>
 #include <linux/module.h>
 #include <linux/malloc.h>
 #include <linux/types.h>

drivers/sound/msnd_classic.h

@@ -30,6 +30,8 @@
 #ifndef __MSND_CLASSIC_H
 #define __MSND_CLASSIC_H
 
+#include <linux/config.h>
+
 #define DSP_NUMIO		0x10
 
 #define	HP_MEMM			0x08

drivers/sound/msnd_pinnacle.c

@@ -24,7 +24,6 @@
  *
  ********************************************************************/
 
-#include <linux/config.h>
 #include <linux/module.h>
 #include <linux/malloc.h>
 #include <linux/types.h>

drivers/sound/msnd_pinnacle.h

@@ -30,6 +30,8 @@
 #ifndef __MSND_PINNACLE_H
 #define __MSND_PINNACLE_H
 
+#include <linux/config.h>
+
 #define DSP_NUMIO		0x08
 
 #define	HP_DSPR			0x04

drivers/sound/sound_core.c

@@ -34,7 +34,6 @@
  *	locking at some point in 2.3.x.
  */
 
-#include <linux/config.h>
 #include <linux/module.h>
 #include <linux/malloc.h>
 #include <linux/types.h>

drivers/video/S3triofb.c

@@ -23,6 +23,7 @@
 
 */
 
+#include <linux/config.h>
 #include <linux/kernel.h>
 #include <linux/module.h>
 #include <linux/errno.h>

drivers/video/fbcon-ilbm.c

@@ -201,7 +201,7 @@ void fbcon_ilbm_putcs(struct vc_data *conp, struct display *p, const char *s,
 #if defined(__BIG_ENDIAN)
 		d = *cdat1++<<24 | *cdat2++<<16 | *cdat3++<<8 | *cdat4++;
 #elif defined(__LITTLE_ENDIAN)
-		d = *cdat1++ | *cdat2++<<8 | *cdat3++<<16 | *cdat4++<<32);
+		d = *cdat1++ | *cdat2++<<8 | *cdat3++<<16 | *cdat4++<<24;
 #else
 #error FIXME: No endianness??
 #endif

drivers/video/fbcon-iplan2p2.c

@@ -10,6 +10,7 @@
  *  more details.
  */
 
+#include <linux/config.h>
 #include <linux/module.h>
 #include <linux/tty.h>
 #include <linux/console.h>

drivers/video/fbcon-iplan2p4.c

@@ -10,6 +10,7 @@
  *  more details.
  */
 
+#include <linux/config.h>
 #include <linux/module.h>
 #include <linux/tty.h>
 #include <linux/console.h>

drivers/video/fbcon-iplan2p8.c

@@ -10,6 +10,7 @@
  *  more details.
  */
 
+#include <linux/config.h>
 #include <linux/module.h>
 #include <linux/tty.h>
 #include <linux/console.h>

drivers/video/hpfb.c

@@ -6,7 +6,6 @@
  * No! -- Jes
  */
 
-#include <linux/config.h>
 #include <linux/module.h>
 #include <linux/kernel.h>
 #include <linux/sched.h>

fs/coda/stats.c

@@ -7,7 +7,6 @@
  *
  */
 
-#include <linux/config.h>
 #include <linux/sched.h>
 #include <linux/mm.h>
 #include <linux/sysctl.h>

fs/proc/array.c

@@ -232,7 +232,7 @@ static int get_kstat(char * buffer)
 
 #ifdef __SMP__
 	len = sprintf(buffer,
-		"CPU  %u %u %u %lu\n",
+		"cpu  %u %u %u %lu\n",
 		kstat.cpu_user,
 		kstat.cpu_nice,
 		kstat.cpu_system,

fs/select.c

@@ -297,21 +297,25 @@ static int do_poll(unsigned int nfds, struct pollfd *fds, poll_table *wait)
 
 		current->state = TASK_INTERRUPTIBLE;
 		for (fdpnt = fds, j = 0; j < nfds; j++, fdpnt++) {
+			int fd;
 			unsigned int mask;
-			struct file * file;
 
-			mask = POLLNVAL;
-			/* poll_wait increments f_count if needed */
-			file = fcheck(fdpnt->fd);
-			if (file != NULL) {
-				mask = DEFAULT_POLLMASK;
-				if (file->f_op && file->f_op->poll)
-					mask = file->f_op->poll(file, wait);
-				mask &= fdpnt->events | POLLERR | POLLHUP;
-			}
-			if (mask) {
-				wait = NULL;
-				count++;
+			mask = 0;
+			fd = fdpnt->fd;
+			if (fd >= 0) {
+				/* poll_wait increments f_count if needed */
+				struct file * file = fcheck(fd);
+				mask = POLLNVAL;
+				if (file != NULL) {
+					mask = DEFAULT_POLLMASK;
+					if (file->f_op && file->f_op->poll)
+						mask = file->f_op->poll(file, wait);
+					mask &= fdpnt->events | POLLERR | POLLHUP;
+				}
+				if (mask) {
+					wait = NULL;
+					count++;
+				}
 			}
 			fdpnt->revents = mask;
 		}

fs/sysv/CHANGES

@@ -3,7 +3,7 @@ Mon Dec 15 1997	  Krzysztof G. Baranowski <kgb@manjak.knm.org.pl>
 
 Fri Jan 23 1998   Krzysztof G. Baranowski <kgb@manjak.knm.org.pl>
 	*    inode.c: corrected 1 track offset setting (in sb->sv_block_base).
-		      Originally it was overriden (by setting to zero)
+		      Originally it was overridden (by setting to zero)
 		      in detected_[xenix,sysv4,sysv2,coherent]. Thanks
 		      to Andrzej Krzysztofowicz <ankry@mif.pg.gda.pl>
 		      for identifying the problem.

fs/sysv/Makefile

 #
-# Makefile for the Linux SystemV/Coherent-filesystem routines.
+# Makefile for the Linux SystemV/Coherent filesystem routines.
 #
 # Note! Dependencies are done automagically by 'make dep', which also
 # removes any old dependencies. DON'T put your own dependencies here
-# unless it's something special (ie not a .c file).
+# unless it's something special (not a .c file).
 #
-# Note 2! The CFLAGS definitions are now in the main makefile...
+# Note 2! The CFLAGS definitions are now in the main makefile.
 
 O_TARGET := sysv.o
 O_OBJS   := ialloc.o balloc.o inode.o file.o dir.o symlink.o namei.o \

fs/sysv/file.c

@@ -36,7 +36,7 @@
 static ssize_t sysv_file_write(struct file *, const char *, size_t, loff_t *);
 
 /*
- * We have mostly NULL's here: the current defaults are ok for
+ * We have mostly NULLs here: the current defaults are OK for
  * the coh filesystem.
  */
 static struct file_operations sysv_file_operations = {
@@ -220,7 +220,7 @@ static ssize_t sysv_file_write(struct file * filp, const char * buf,
 		return -EINVAL;
 	}
 /*
- * ok, append may not work when many processes are writing at the same time
+ * OK, append may not work when many processes are writing at the same time
  * but so what. That way leads to madness anyway.
  * But we need to protect against simultaneous truncate as we may end up
  * writing our data into blocks that have meanwhile been incorporated into

fs/sysv/truncate.c

@@ -24,7 +24,7 @@
 
 /*
  * Truncate has the most races in the whole filesystem: coding it is
- * a pain in the a**. Especially as I don't do any locking...
+ * a pain in the a**, especially as I don't do any locking.
  *
  * The code may look a bit weird, but that's just because I've tried to
  * handle things like file-size changes in a somewhat graceful manner.

include/asm-i386/unistd.h

@@ -192,6 +192,7 @@
 #define __NR_capget		184
 #define __NR_capset		185
 #define __NR_sigaltstack	186
+#define __NR_sendfile		187
 
 /* user-visible error numbers are in the range -1 - -122: see <asm-i386/errno.h> */
 

include/asm-m68k/pgtable.h

 #ifndef _M68K_PGTABLE_H
 #define _M68K_PGTABLE_H
 
+#include <linux/config.h>
 #include <asm/setup.h>
 
 #ifndef __ASSEMBLY__

include/linux/console_compat.h

@@ -11,6 +11,8 @@
 #ifndef _LINUX_CONSOLE_COMPAT_H_
 #define _LINUX_CONSOLE_COMPAT_H_
 
+#include <linux/config.h>
+
 #undef video_num_columns
 #undef video_num_lines
 #undef video_size_row

include/linux/console_struct.h

@@ -10,8 +10,6 @@
  */
 #define CUR_DEFAULT CUR_UNDERLINE
 
-#include <linux/config.h>
-
 #define NPAR 16
 
 struct vc_data {

include/linux/selection.h

@@ -4,8 +4,6 @@
  * Interface between console.c, tty_io.c, vt.c, vc_screen.c and selection.c
  */
 
-#include <linux/config.h>
-
 extern int sel_cons;
 
 extern void clear_selection(void);
@@ -60,8 +58,6 @@ extern void putconsxy(int currcons, char *p);
 
 /* how to access screen memory */
 
-#include <linux/config.h>
-
 static inline void scr_writew(unsigned short val, unsigned short *addr)
 {
 	/* simply store the value in the "shadow screen" memory */

mm/filemap.c

@@ -567,6 +567,23 @@ static inline unsigned long generic_file_readahead(int reada_ok,
 	return page_cache;
 }
 
+/*
+ * "descriptor" for what we're up to with a read.
+ * This allows us to use the same read code yet
+ * have multiple different users of the data that
+ * we read from a file.
+ *
+ * The simplest case just copies the data to user
+ * mode.
+ */
+typedef struct {
+	size_t written;
+	size_t count;
+	char * buf;
+	int error;
+} read_descriptor_t;
+
+typedef int (*read_actor_t)(read_descriptor_t *, const char *, unsigned long);
 
 /*
  * This is a generic file read routine, and uses the
@@ -576,23 +593,14 @@ static inline unsigned long generic_file_readahead(int reada_ok,
  * This is really ugly. But the goto's actually try to clarify some
  * of the logic when it comes to error handling etc.
  */
-
-ssize_t generic_file_read(struct file * filp, char * buf,
-			  size_t count, loff_t *ppos)
+static void do_generic_file_read(struct file * filp, loff_t *ppos, read_descriptor_t * desc, read_actor_t actor)
 {
 	struct dentry *dentry = filp->f_dentry;
 	struct inode *inode = dentry->d_inode;
-	ssize_t error, read;
 	size_t pos, pgpos, page_cache;
 	int reada_ok;
 	int max_readahead = get_max_readahead(inode);
 
-	if (!access_ok(VERIFY_WRITE, buf, count))
-		return -EFAULT;
-	if (!count)
-		return 0;
-	error = 0;
-	read = 0;
 	page_cache = 0;
 
 	pos = *ppos;
@@ -620,12 +628,12 @@ ssize_t generic_file_read(struct file * filp, char * buf,
  * Then, at least MIN_READAHEAD if read ahead is ok,
  * and at most MAX_READAHEAD in all cases.
  */
-	if (pos + count <= (PAGE_SIZE >> 1)) {
+	if (pos + desc->count <= (PAGE_SIZE >> 1)) {
 		filp->f_ramax = 0;
 	} else {
 		unsigned long needed;
 
-		needed = ((pos + count) & PAGE_MASK) - pgpos;
+		needed = ((pos + desc->count) & PAGE_MASK) - pgpos;
 
 		if (filp->f_ramax < needed)
 			filp->f_ramax = needed;
@@ -678,20 +686,20 @@ ssize_t generic_file_read(struct file * filp, char * buf,
 
 		offset = pos & ~PAGE_MASK;
 		nr = PAGE_SIZE - offset;
-		if (nr > count)
-			nr = count;
 		if (nr > inode->i_size - pos)
 			nr = inode->i_size - pos;
-		nr -= copy_to_user(buf, (void *) (page_address(page) + offset), nr);
-		release_page(page);
-		error = -EFAULT;
-		if (!nr)
-			break;
-		buf += nr;
+
+		/*
+		 * The actor routine returns how many bytes were actually used..
+		 * NOTE! This may not be the same as how much of a user buffer
+		 * we filled up (we may be padding etc), so we can only update
+		 * "pos" here (the actor routine has to update the user buffer
+		 * pointers and the remaining count).
+		 */
+		nr = actor(desc, (const char *) (page_address(page) + offset), nr);
 		pos += nr;
-		read += nr;
-		count -= nr;
-		if (count)
+		release_page(page);
+		if (nr && desc->count)
 			continue;
 		break;
 	}
@@ -709,7 +717,7 @@ ssize_t generic_file_read(struct file * filp, char * buf,
 			 */
 			if (page_cache)
 				continue;
-			error = -ENOMEM;
+			desc->error = -ENOMEM;
 			break;
 		}
 
@@ -738,11 +746,14 @@ ssize_t generic_file_read(struct file * filp, char * buf,
 		if (reada_ok && filp->f_ramax > MIN_READAHEAD)
 			filp->f_ramax = MIN_READAHEAD;
 
-		error = inode->i_op->readpage(filp, page);
-		if (!error)
-			goto found_page;
-		release_page(page);
-		break;
+		{
+			int error = inode->i_op->readpage(filp, page);
+			if (!error)
+				goto found_page;
+			desc->error = error;
+			release_page(page);
+			break;
+		}
 
 page_read_error:
 		/*
@@ -750,15 +761,18 @@ ssize_t generic_file_read(struct file * filp, char * buf,
 		 * Try to re-read it _once_. We do this synchronously,
 		 * because this happens only if there were errors.
 		 */
-		error = inode->i_op->readpage(filp, page);
-		if (!error) {
-			wait_on_page(page);
-			if (PageUptodate(page) && !PageError(page))
-				goto success;
-			error = -EIO; /* Some unspecified error occurred.. */
+		{
+			int error = inode->i_op->readpage(filp, page);
+			if (!error) {
+				wait_on_page(page);
+				if (PageUptodate(page) && !PageError(page))
+					goto success;
+				error = -EIO; /* Some unspecified error occurred.. */
+			}
+			desc->error = error;
+			release_page(page);
+			break;
 		}
-		release_page(page);
-		break;
 	}
 
 	*ppos = pos;
@@ -766,9 +780,146 @@ ssize_t generic_file_read(struct file * filp, char * buf,
 	if (page_cache)
 		free_page(page_cache);
 	UPDATE_ATIME(inode);
-	if (!read)
-		read = error;
-	return read;
+}
+
+static int file_read_actor(read_descriptor_t * desc, const char *area, unsigned long size)
+{
+	unsigned long left;
+	unsigned long count = desc->count;
+
+	if (size > count)
+		size = count;
+	left = __copy_to_user(desc->buf, area, size);
+	if (left) {
+		size -= left;
+		desc->error = -EFAULT;
+	}
+	desc->count = count - size;
+	desc->written += size;
+	desc->buf += size;
+	return size;
+}
+
+/*
+ * This is the "read()" routine for all filesystems
+ * that can use the page cache directly.
+ */
+ssize_t generic_file_read(struct file * filp, char * buf, size_t count, loff_t *ppos)
+{
+	ssize_t retval;
+
+	retval = -EFAULT;
+	if (access_ok(VERIFY_WRITE, buf, count)) {
+		retval = 0;
+		if (count) {
+			read_descriptor_t desc;
+
+			desc.written = 0;
+			desc.count = count;
+			desc.buf = buf;
+			desc.error = 0;
+			do_generic_file_read(filp, ppos, &desc, file_read_actor);
+
+			retval = desc.written;
+			if (!retval)
+				retval = desc.error;
+		}
+	}
+	return retval;
+}
+
+static int file_send_actor(read_descriptor_t * desc, const char *area, unsigned long size)
+{
+	ssize_t written;
+	unsigned long count = desc->count;
+	struct file *file = (struct file *) desc->buf;
+	struct inode *inode = file->f_dentry->d_inode;
+
+	if (size > count)
+		size = count;
+	down(&inode->i_sem);
+	set_fs(KERNEL_DS);
+	written = file->f_op->write(file, area, size, &file->f_pos);
+	set_fs(USER_DS);
+	up(&inode->i_sem);
+	if (written < 0) {
+		desc->error = written;
+		written = 0;
+	}
+	desc->count = count - written;
+	desc->written += written;
+	return written;
+}
+
+asmlinkage ssize_t sys_sendfile(int out_fd, int in_fd, size_t count)
+{
+	ssize_t retval;
+	struct file * in_file, * out_file;
+	struct inode * in_inode, * out_inode;
+
+	lock_kernel();
+
+	/*
+	 * Get input file, and verify that it is ok..
+	 */
+	retval = -EBADF;
+	in_file = fget(in_fd);
+	if (!in_file)
+		goto out;
+	if (!(in_file->f_mode & FMODE_READ))
+		goto fput_in;
+	retval = -EINVAL;
+	in_inode = in_file->f_dentry->d_inode;
+	if (!in_inode)
+		goto fput_in;
+	if (!in_inode->i_op || !in_inode->i_op->readpage)
+		goto fput_in;
+	retval = locks_verify_area(FLOCK_VERIFY_READ, in_inode, in_file, in_file->f_pos, count);
+	if (retval)
+		goto fput_in;
+
+	/*
+	 * Get output file, and verify that it is ok..
+	 */
+	retval = -EBADF;
+	out_file = fget(out_fd);
+	if (!out_file)
+		goto fput_in;
+	if (!(out_file->f_mode & FMODE_WRITE))
+		goto fput_out;
+	retval = -EINVAL;
+	if (!out_file->f_op || !out_file->f_op->write)
+		goto fput_out;
+	out_inode = out_file->f_dentry->d_inode;
+	if (!out_inode)
+		goto fput_out;
+	retval = locks_verify_area(FLOCK_VERIFY_WRITE, out_inode, out_file, out_file->f_pos, count);
+	if (retval)
+		goto fput_out;
+
+	retval = 0;
+	if (count) {
+		read_descriptor_t desc;
+
+		desc.written = 0;
+		desc.count = count;
+		desc.buf = (char *) out_file;
+		desc.error = 0;
+		do_generic_file_read(in_file, &in_file->f_pos, &desc, file_send_actor);
+
+		retval = desc.written;
+		if (!retval)
+			retval = desc.error;
+	}
+
+
+fput_out:
+	fput(out_file);
+fput_in:
+	fput(in_file);
+out:
+	unlock_kernel();
+	return retval;
 }
 
 /*