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/*
* Copyright (c) 2000 Silicon Graphics, Inc. All Rights Reserved.
*
* This program is free software; you can redistribute it and/or modify it
* under the terms of version 2 of the GNU General Public License as
* published by the Free Software Foundation.
*
* This program is distributed in the hope that it would be useful, but
* WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.
*
* Further, this software is distributed without any warranty that it is
* free of the rightful claim of any third person regarding infringement
* or the like. Any license provided herein, whether implied or
* otherwise, applies only to this software file. Patent licenses, if
* any, provided herein do not apply to combinations of this program with
* other software, or any other product whatsoever.
*
* You should have received a copy of the GNU General Public License along
* with this program; if not, write the Free Software Foundation, Inc., 59
* Temple Place - Suite 330, Boston MA 02111-1307, USA.
*
* Contact information: Silicon Graphics, Inc., 1600 Amphitheatre Pkwy,
* Mountain View, CA 94043, or:
*
* http://www.sgi.com
*
* For further information regarding this notice, see:
*
* http://oss.sgi.com/projects/GenInfo/SGIGPLNoticeExplan/
*/
#include <xfs.h>
#include <linux/dcache.h>
#include <linux/pagemap.h>
#include <linux/slab.h>
STATIC ssize_t
linvfs_read(
struct file *filp,
char *buf,
size_t size,
loff_t *offset)
{
vnode_t *vp;
int err;
uio_t uio;
iovec_t iov;
vp = LINVFS_GET_VP(filp->f_dentry->d_inode);
ASSERT(vp);
uio.uio_iov = &iov;
uio.uio_offset = *offset;
uio.uio_fp = filp;
uio.uio_iovcnt = 1;
uio.uio_iov->iov_base = buf;
uio.uio_iov->iov_len = uio.uio_resid = size;
XFS_STATS_INC(xfsstats.xs_read_calls);
XFS_STATS_ADD(xfsstats.xs_read_bytes, size);
VOP_READ(vp, &uio, 0, NULL, NULL, err);
*offset = uio.uio_offset;
/*
* If we got a return value, it was an error
* Flip to negative & return that
* Otherwise, return bytes actually read
*/
return(err ? -err : size-uio.uio_resid);
}
STATIC ssize_t
linvfs_write(
struct file *file,
const char *buf,
size_t count,
loff_t *ppos)
{
struct inode *inode = file->f_dentry->d_inode;
unsigned long limit = current->rlim[RLIMIT_FSIZE].rlim_cur;
loff_t pos;
vnode_t *vp;
int err; /* Use negative errors in this f'n */
uio_t uio;
iovec_t iov;
if ((ssize_t) count < 0)
return -EINVAL;
if (!access_ok(VERIFY_READ, buf, count))
return -EFAULT;
down(&inode->i_sem);
pos = *ppos;
err = -EINVAL;
if (pos < 0)
goto out;
err = file->f_error;
if (err) {
file->f_error = 0;
goto out;
}
if (!S_ISBLK(inode->i_mode) && file->f_flags & O_APPEND)
pos = inode->i_size;
/*
* Check whether we've reached the file size limit.
*/
err = -EFBIG;
if (limit != RLIM_INFINITY) {
if (pos >= limit) {
send_sig(SIGXFSZ, current, 0);
goto out;
}
if (pos > 0xFFFFFFFFULL || count > limit - (u32)pos) {
/* send_sig(SIGXFSZ, current, 0); */
count = limit - (u32)pos;
}
}
/*
* LFS rule
*/
if ( pos + count > MAX_NON_LFS && !(file->f_flags&O_LARGEFILE)) {
if (pos >= MAX_NON_LFS) {
send_sig(SIGXFSZ, current, 0);
goto out;
}
if (count > MAX_NON_LFS - (u32)pos) {
/* send_sig(SIGXFSZ, current, 0); */
count = MAX_NON_LFS - (u32)pos;
}
}
/*
* Are we about to exceed the fs block limit ?
*
* If we have written data it becomes a short write
* If we have exceeded without writing data we send
* a signal and give them an EFBIG.
*
* Linus frestrict idea will clean these up nicely..
*/
if (!S_ISBLK(inode->i_mode)) {
if (pos >= inode->i_sb->s_maxbytes)
{
if (count || pos > inode->i_sb->s_maxbytes) {
send_sig(SIGXFSZ, current, 0);
err = -EFBIG;
goto out;
}
/* zero-length writes at ->s_maxbytes are OK */
}
if (pos + count > inode->i_sb->s_maxbytes)
count = inode->i_sb->s_maxbytes - pos;
} else {
if (is_read_only(inode->i_rdev)) {
err = -EPERM;
goto out;
}
if (pos >= inode->i_size) {
if (count || pos > inode->i_size) {
err = -ENOSPC;
goto out;
}
}
if (pos + count > inode->i_size)
count = inode->i_size - pos;
}
err = 0;
if (count == 0)
goto out;
XFS_STATS_INC(xfsstats.xs_write_calls);
XFS_STATS_ADD(xfsstats.xs_write_bytes, count);
vp = LINVFS_GET_VP(inode);
ASSERT(vp);
uio.uio_iov = &iov;
uio.uio_offset = pos;
uio.uio_fp = file;
uio.uio_iovcnt = 1;
uio.uio_iov->iov_base = (void *)buf;
uio.uio_iov->iov_len = uio.uio_resid = count;
VOP_WRITE(vp, &uio, file->f_flags, NULL, NULL, err);
/* xfs_write returns positive errors */
err = -err; /* if it's 0 this is harmless */
*ppos = pos = uio.uio_offset;
count -= uio.uio_resid;
out:
up(&inode->i_sem);
/*
* If we got an error return that.
* Otherwise, return bytes actually written
*/
return(err ? err : count);
}
STATIC int
linvfs_open(
struct inode *inode,
struct file *filp)
{
vnode_t *vp = LINVFS_GET_VP(inode);
vnode_t *newvp;
int error;
if (!(filp->f_flags & O_LARGEFILE) && inode->i_size > MAX_NON_LFS)
return -EFBIG;
ASSERT(vp);
VOP_OPEN(vp, &newvp, 0, get_current_cred(), error);
return -error;
}
STATIC int
linvfs_release(
struct inode *inode,
struct file *filp)
{
vnode_t *vp = LINVFS_GET_VP(inode);
int error = 0;
if (vp)
VOP_RELEASE(vp, error);
return -error;
}
STATIC int
linvfs_fsync(
struct file *filp,
struct dentry *dentry,
int datasync)
{
struct inode *inode = dentry->d_inode;
vnode_t *vp = LINVFS_GET_VP(inode);
int error;
int flags = FSYNC_WAIT;
if (datasync)
flags |= FSYNC_DATA;
ASSERT(vp);
VOP_FSYNC(vp, flags, get_current_cred(),
(off_t)0, (off_t)-1, error);
return -error;
}
/*
* linvfs_readdir maps to VOP_READDIR().
* We need to build a uio, cred, ...
*/
#define nextdp(dp) ((struct xfs_dirent *)((char *)(dp) + (dp)->d_reclen))
STATIC int
linvfs_readdir(
struct file *filp,
void *dirent,
filldir_t filldir)
{
int error = 0;
vnode_t *vp;
uio_t uio;
iovec_t iov;
int eof = 0;
cred_t cred; /* Temporary cred workaround */
caddr_t read_buf;
int namelen, size = 0;
size_t rlen = PAGE_CACHE_SIZE << 2;
off_t start_offset;
xfs_dirent_t *dbp = NULL;
vp = LINVFS_GET_VP(filp->f_dentry->d_inode);
ASSERT(vp);
/* Try fairly hard to get memory */
do {
if ((read_buf = (caddr_t)kmalloc(rlen, GFP_KERNEL)))
break;
rlen >>= 1;
} while (rlen >= 1024);
if (read_buf == NULL)
return -ENOMEM;
uio.uio_iov = &iov;
uio.uio_fmode = filp->f_mode;
uio.uio_segflg = UIO_SYSSPACE;
uio.uio_offset = filp->f_pos;
while (!eof) {
uio.uio_resid = iov.iov_len = rlen;
iov.iov_base = read_buf;
uio.uio_iovcnt = 1;
start_offset = uio.uio_offset;
VOP_READDIR(vp, &uio, &cred, &eof, error);
if ((uio.uio_offset == start_offset) || error) {
size = 0;
break;
}
size = rlen - uio.uio_resid;
dbp = (xfs_dirent_t *)read_buf;
while (size > 0) {
namelen = strlen(dbp->d_name);
if (filldir(dirent, dbp->d_name, namelen,
(off_t) dbp->d_off,
(linux_ino_t) dbp->d_ino,
DT_UNKNOWN)) {
goto done;
}
size -= dbp->d_reclen;
dbp = nextdp(dbp);
}
}
done:
if (!error) {
if (size == 0)
filp->f_pos = uio.uio_offset;
else if (dbp)
filp->f_pos = dbp->d_off;
}
kfree(read_buf);
return -error;
}
#ifdef CONFIG_HAVE_XFS_DMAPI
STATIC int
linvfs_dmapi_map_event(
struct file *filp,
struct vm_area_struct *vma,
unsigned int wantflag)
{
vnode_t *vp;
xfs_inode_t *ip;
bhv_desc_t *bdp;
int ret = 0;
dm_fcntl_mapevent_t maprq;
dm_eventtype_t max_event = DM_EVENT_READ;
vp = LINVFS_GET_VP(filp->f_dentry->d_inode);
ASSERT(vp);
if ((vp->v_type != VREG) || !(vp->v_vfsp->vfs_flag & VFS_DMI))
return 0;
/* If they specifically asked for 'read', then give it to them.
* Otherwise, see if it's possible to give them 'write'.
*/
if( wantflag & VM_READ ){
max_event = DM_EVENT_READ;
}
else if( ! (vma->vm_flags & VM_DENYWRITE) ) {
if((wantflag & VM_WRITE) || (vma->vm_flags & VM_WRITE))
max_event = DM_EVENT_WRITE;
}
if( (wantflag & VM_WRITE) && (max_event != DM_EVENT_WRITE) ){
return -EACCES;
}
maprq.max_event = max_event;
/* Figure out how much of the file is being requested by the user. */
maprq.length = 0; /* whole file, for now */
bdp = bhv_base_unlocked(VN_BHV_HEAD(vp));
ip = XFS_BHVTOI(bdp);
if(DM_EVENT_ENABLED(vp->v_vfsp, ip, max_event)){
xfs_dm_mapevent(bdp, 0, 0, &maprq);
ret = maprq.error;
}
return -ret;
}
#endif
STATIC int
linvfs_generic_file_mmap(
struct file *filp,
struct vm_area_struct *vma)
{
vnode_t *vp;
int ret;
/* this will return a (-) error so flip */
ret = -generic_file_mmap(filp, vma);
if (!ret) {
vattr_t va, *vap;
vap = &va;
vap->va_mask = AT_UPDATIME;
vp = LINVFS_GET_VP(filp->f_dentry->d_inode);
ASSERT(vp);
VOP_SETATTR(vp, vap, AT_UPDATIME, NULL, ret);
if(ret)
goto out;
#ifdef CONFIG_HAVE_XFS_DMAPI /* Temporary until dmapi is in main kernel */
if( filp->f_op->dmapi_map_event )
ret = -filp->f_op->dmapi_map_event( filp, vma, 0 );
#endif
}
out:
return(-ret);
}
STATIC int
linvfs_ioctl(
struct inode *inode,
struct file *filp,
unsigned int cmd,
unsigned long arg)
{
int error;
vnode_t *vp = LINVFS_GET_VP(inode);
ASSERT(vp);
VOP_IOCTL(vp, inode, filp, cmd, arg, error);
VMODIFY(vp);
/* NOTE: some of the ioctl's return positive #'s as a
* byte count indicating success, such as
* readlink_by_handle. So we don't "sign flip"
* like most other routines. This means true
* errors need to be returned as a negative value.
*/
return error;
}
struct file_operations linvfs_file_operations =
{
llseek: generic_file_llseek,
read: linvfs_read,
write: linvfs_write,
ioctl: linvfs_ioctl,
mmap: linvfs_generic_file_mmap,
open: linvfs_open,
release: linvfs_release,
fsync: linvfs_fsync,
#ifdef CONFIG_HAVE_XFS_DMAPI /* Temporary until dmapi is in main kernel */
dmapi_map_event: linvfs_dmapi_map_event,
#endif
};
struct file_operations linvfs_dir_operations = {
read: generic_read_dir,
readdir: linvfs_readdir,
ioctl: linvfs_ioctl,
fsync: linvfs_fsync,
};
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