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#define MSNFS /* HACK HACK */
/*
* linux/fs/nfsd/vfs.c
*
* File operations used by nfsd. Some of these have been ripped from
* other parts of the kernel because they weren't in ksyms.c, others
* are partial duplicates with added or changed functionality.
*
* Note that several functions dget() the dentry upon which they want
* to act, most notably those that create directory entries. Response
* dentry's are dput()'d if necessary in the release callback.
* So if you notice code paths that apparently fail to dput() the
* dentry, don't worry--they have been taken care of.
*
* Copyright (C) 1995-1999 Olaf Kirch <okir@monad.swb.de>
*/
#include <linux/config.h>
#include <linux/version.h>
#include <linux/string.h>
#include <linux/sched.h>
#include <linux/errno.h>
#include <linux/locks.h>
#include <linux/fs.h>
#include <linux/major.h>
#include <linux/ext2_fs.h>
#include <linux/proc_fs.h>
#include <linux/stat.h>
#include <linux/fcntl.h>
#include <linux/net.h>
#include <linux/unistd.h>
#include <linux/slab.h>
#include <linux/in.h>
#define __NO_VERSION__
#include <linux/module.h>
#include <linux/sunrpc/svc.h>
#include <linux/nfsd/nfsd.h>
#ifdef CONFIG_NFSD_V3
#include <linux/nfs3.h>
#include <linux/nfsd/xdr3.h>
#endif /* CONFIG_NFSD_V3 */
#include <linux/nfsd/nfsfh.h>
#include <linux/quotaops.h>
#include <asm/uaccess.h>
#define NFSDDBG_FACILITY NFSDDBG_FILEOP
#define NFSD_PARANOIA
/* We must ignore files (but only files) which might have mandatory
* locks on them because there is no way to know if the accesser has
* the lock.
*/
#define IS_ISMNDLK(i) (S_ISREG((i)->i_mode) && MANDATORY_LOCK(i))
/*
* This is a cache of readahead params that help us choose the proper
* readahead strategy. Initially, we set all readahead parameters to 0
* and let the VFS handle things.
* If you increase the number of cached files very much, you'll need to
* add a hash table here.
*/
struct raparms {
struct raparms *p_next;
unsigned int p_count;
ino_t p_ino;
dev_t p_dev;
unsigned long p_reada,
p_ramax,
p_raend,
p_ralen,
p_rawin;
};
static struct raparms * raparml;
static struct raparms * raparm_cache;
/*
* Look up one component of a pathname.
* N.B. After this call _both_ fhp and resfh need an fh_put
*
* If the lookup would cross a mountpoint, and the mounted filesystem
* is exported to the client with NFSEXP_CROSSMNT, then the lookup is
* accepted as it stands and the mounted directory is
* returned. Otherwise the covered directory is returned.
* NOTE: this mountpoint crossing is not supported properly by all
* clients and is explicitly disallowed for NFSv3
* NeilBrown <neilb@cse.unsw.edu.au>
*/
int
nfsd_lookup(struct svc_rqst *rqstp, struct svc_fh *fhp, const char *name,
int len, struct svc_fh *resfh)
{
struct svc_export *exp;
struct dentry *dparent;
struct dentry *dentry;
int err;
dprintk("nfsd: nfsd_lookup(fh %s, %.*s)\n", SVCFH_fmt(fhp), len,name);
/* Obtain dentry and export. */
err = fh_verify(rqstp, fhp, S_IFDIR, MAY_EXEC);
if (err)
goto out;
dparent = fhp->fh_dentry;
exp = fhp->fh_export;
err = nfserr_acces;
/* Lookup the name, but don't follow links */
if (isdotent(name, len)) {
if (len==1)
dentry = dget(dparent);
else { /* must be ".." */
/* checking mountpoint crossing is very different when stepping up */
if (dparent == exp->ex_dentry) {
if (!EX_CROSSMNT(exp))
dentry = dget(dparent); /* .. == . just like at / */
else
{
struct svc_export *exp2 = NULL;
struct dentry *dp;
struct vfsmount *mnt = mntget(exp->ex_mnt);
dentry = dget(dparent);
while(follow_up(&mnt, &dentry))
;
dp = dget(dentry->d_parent);
dput(dentry);
dentry = dp;
for ( ; exp2 == NULL && dp->d_parent != dp;
dp=dp->d_parent)
exp2 = exp_get(exp->ex_client, dp->d_inode->i_dev, dp->d_inode->i_ino);
if (exp2==NULL) {
dput(dentry);
dentry = dget(dparent);
} else {
exp = exp2;
}
mntput(mnt);
}
} else
dentry = dget(dparent->d_parent);
}
} else {
fh_lock(fhp);
dentry = lookup_one_len(name, dparent, len);
err = PTR_ERR(dentry);
if (IS_ERR(dentry))
goto out_nfserr;
/*
* check if we have crossed a mount point ...
*/
if (d_mountpoint(dentry)) {
struct svc_export *exp2 = NULL;
struct vfsmount *mnt = mntget(exp->ex_mnt);
struct dentry *mounts = dget(dentry);
while (follow_down(&mnt,&mounts)&&d_mountpoint(mounts))
;
exp2 = exp_get(rqstp->rq_client,
mounts->d_inode->i_dev,
mounts->d_inode->i_ino);
if (exp2 && EX_CROSSMNT(exp2)) {
/* successfully crossed mount point */
exp = exp2;
dput(dentry);
dentry = mounts;
} else
dput(mounts);
mntput(mnt);
}
}
/*
* Note: we compose the file handle now, but as the
* dentry may be negative, it may need to be updated.
*/
err = fh_compose(resfh, exp, dentry, fhp);
if (!err && !dentry->d_inode)
err = nfserr_noent;
out:
return err;
out_nfserr:
err = nfserrno(err);
goto out;
}
/*
* Set various file attributes.
* N.B. After this call fhp needs an fh_put
*/
int
nfsd_setattr(struct svc_rqst *rqstp, struct svc_fh *fhp, struct iattr *iap,
int check_guard, time_t guardtime)
{
struct dentry *dentry;
struct inode *inode;
int accmode = MAY_SATTR;
int ftype = 0;
int imode;
int err;
int size_change = 0;
if (iap->ia_valid & (ATTR_ATIME | ATTR_MTIME | ATTR_SIZE))
accmode |= MAY_WRITE|MAY_OWNER_OVERRIDE;
if (iap->ia_valid & ATTR_SIZE)
ftype = S_IFREG;
/* Get inode */
err = fh_verify(rqstp, fhp, ftype, accmode);
if (err || !iap->ia_valid)
goto out;
dentry = fhp->fh_dentry;
inode = dentry->d_inode;
err = inode_change_ok(inode, iap);
/* could be a "touch" (utimes) request where the user is not the owner but does
* have write permission. In this case the user should be allowed to set
* both times to the current time. We could just assume any such SETATTR
* is intended to set the times to "now", but we do a couple of simple tests
* to increase our confidence.
*/
#define BOTH_TIME_SET (ATTR_ATIME_SET | ATTR_MTIME_SET)
#define MAX_TOUCH_TIME_ERROR (30*60)
if (err
&& (iap->ia_valid & BOTH_TIME_SET) == BOTH_TIME_SET
&& iap->ia_mtime == iap->ia_atime
) {
/* looks good. now just make sure time is in the right ballpark.
* solaris, at least, doesn't seem to care what the time request is
*/
time_t delta = iap->ia_atime - CURRENT_TIME;
if (delta<0) delta = -delta;
if (delta < MAX_TOUCH_TIME_ERROR) {
/* turn off ATTR_[AM]TIME_SET but leave ATTR_[AM]TIME
* this will cause notify_change to set these times to "now"
*/
iap->ia_valid &= ~BOTH_TIME_SET;
err = inode_change_ok(inode, iap);
}
}
if (err)
goto out_nfserr;
/* The size case is special. It changes the file as well as the attributes. */
if (iap->ia_valid & ATTR_SIZE) {
if (iap->ia_size < inode->i_size) {
err = nfsd_permission(fhp->fh_export, dentry, MAY_TRUNC|MAY_OWNER_OVERRIDE);
if (err)
goto out;
}
/*
* If we are changing the size of the file, then
* we need to break all leases.
*/
err = get_lease(inode, FMODE_WRITE);
if (err)
goto out_nfserr;
err = get_write_access(inode);
if (err)
goto out_nfserr;
err = locks_verify_truncate(inode, NULL, iap->ia_size);
if (err) {
put_write_access(inode);
goto out_nfserr;
}
DQUOT_INIT(inode);
}
imode = inode->i_mode;
if (iap->ia_valid & ATTR_MODE) {
iap->ia_mode &= S_IALLUGO;
imode = iap->ia_mode |= (imode & ~S_IALLUGO);
}
/* Revoke setuid/setgid bit on chown/chgrp */
if ((iap->ia_valid & ATTR_UID) && (imode & S_ISUID)
&& iap->ia_uid != inode->i_uid) {
iap->ia_valid |= ATTR_MODE;
iap->ia_mode = imode &= ~S_ISUID;
}
if ((iap->ia_valid & ATTR_GID) && (imode & S_ISGID)
&& iap->ia_gid != inode->i_gid) {
iap->ia_valid |= ATTR_MODE;
iap->ia_mode = imode &= ~S_ISGID;
}
/* Change the attributes. */
iap->ia_valid |= ATTR_CTIME;
if (iap->ia_valid & ATTR_SIZE) {
fh_lock(fhp);
size_change = 1;
}
err = nfserr_notsync;
if (!check_guard || guardtime == inode->i_ctime) {
err = notify_change(dentry, iap);
err = nfserrno(err);
}
if (size_change) {
fh_unlock(fhp);
put_write_access(inode);
}
if (!err)
if (EX_ISSYNC(fhp->fh_export))
write_inode_now(inode, 1);
out:
return err;
out_nfserr:
err = nfserrno(err);
goto out;
}
#ifdef CONFIG_NFSD_V3
/*
* Check server access rights to a file system object
*/
struct accessmap {
u32 access;
int how;
};
static struct accessmap nfs3_regaccess[] = {
{ NFS3_ACCESS_READ, MAY_READ },
{ NFS3_ACCESS_EXECUTE, MAY_EXEC },
{ NFS3_ACCESS_MODIFY, MAY_WRITE|MAY_TRUNC },
{ NFS3_ACCESS_EXTEND, MAY_WRITE },
{ 0, 0 }
};
static struct accessmap nfs3_diraccess[] = {
{ NFS3_ACCESS_READ, MAY_READ },
{ NFS3_ACCESS_LOOKUP, MAY_EXEC },
{ NFS3_ACCESS_MODIFY, MAY_EXEC|MAY_WRITE|MAY_TRUNC },
{ NFS3_ACCESS_EXTEND, MAY_EXEC|MAY_WRITE },
{ NFS3_ACCESS_DELETE, MAY_REMOVE },
{ 0, 0 }
};
static struct accessmap nfs3_anyaccess[] = {
/* Some clients - Solaris 2.6 at least, make an access call
* to the server to check for access for things like /dev/null
* (which really, the server doesn't care about). So
* We provide simple access checking for them, looking
* mainly at mode bits
*/
{ NFS3_ACCESS_READ, MAY_READ },
{ NFS3_ACCESS_EXECUTE, MAY_EXEC },
{ NFS3_ACCESS_MODIFY, MAY_WRITE },
{ NFS3_ACCESS_EXTEND, MAY_WRITE },
{ 0, 0 }
};
int
nfsd_access(struct svc_rqst *rqstp, struct svc_fh *fhp, u32 *access)
{
struct accessmap *map;
struct svc_export *export;
struct dentry *dentry;
u32 query, result = 0;
unsigned int error;
error = fh_verify(rqstp, fhp, 0, MAY_NOP);
if (error)
goto out;
export = fhp->fh_export;
dentry = fhp->fh_dentry;
if (S_ISREG(dentry->d_inode->i_mode))
map = nfs3_regaccess;
else if (S_ISDIR(dentry->d_inode->i_mode))
map = nfs3_diraccess;
else
map = nfs3_anyaccess;
query = *access;
for (; map->access; map++) {
if (map->access & query) {
unsigned int err2;
err2 = nfsd_permission(export, dentry, map->how);
switch (err2) {
case nfs_ok:
result |= map->access;
break;
/* the following error codes just mean the access was not allowed,
* rather than an error occurred */
case nfserr_rofs:
case nfserr_acces:
case nfserr_perm:
/* simply don't "or" in the access bit. */
break;
default:
error = err2;
goto out;
}
}
}
*access = result;
out:
return error;
}
#endif /* CONFIG_NFSD_V3 */
/*
* Open an existing file or directory.
* The access argument indicates the type of open (read/write/lock)
* N.B. After this call fhp needs an fh_put
*/
int
nfsd_open(struct svc_rqst *rqstp, struct svc_fh *fhp, int type,
int access, struct file *filp)
{
struct dentry *dentry;
struct inode *inode;
int err;
/* If we get here, then the client has already done an "open", and (hopefully)
* checked permission - so allow OWNER_OVERRIDE in case a chmod has now revoked
* permission */
err = fh_verify(rqstp, fhp, type, access | MAY_OWNER_OVERRIDE);
if (err)
goto out;
dentry = fhp->fh_dentry;
inode = dentry->d_inode;
/* Disallow access to files with the append-only bit set or
* with mandatory locking enabled
*/
err = nfserr_perm;
if (IS_APPEND(inode) || IS_ISMNDLK(inode))
goto out;
if (!inode->i_fop)
goto out;
/*
* Check to see if there are any leases on this file.
* This may block while leases are broken.
*/
err = get_lease(inode, (access & MAY_WRITE) ? FMODE_WRITE : 0);
if (err)
goto out_nfserr;
if ((access & MAY_WRITE) && (err = get_write_access(inode)) != 0)
goto out_nfserr;
memset(filp, 0, sizeof(*filp));
filp->f_op = fops_get(inode->i_fop);
atomic_set(&filp->f_count, 1);
filp->f_dentry = dentry;
filp->f_vfsmnt = fhp->fh_export->ex_mnt;
if (access & MAY_WRITE) {
filp->f_flags = O_WRONLY|O_LARGEFILE;
filp->f_mode = FMODE_WRITE;
DQUOT_INIT(inode);
} else {
filp->f_flags = O_RDONLY|O_LARGEFILE;
filp->f_mode = FMODE_READ;
}
err = 0;
if (filp->f_op && filp->f_op->open) {
err = filp->f_op->open(inode, filp);
if (err) {
fops_put(filp->f_op);
if (access & MAY_WRITE)
put_write_access(inode);
/* I nearly added put_filp() call here, but this filp
* is really on callers stack frame. -DaveM
*/
atomic_dec(&filp->f_count);
}
}
out_nfserr:
if (err)
err = nfserrno(err);
out:
return err;
}
/*
* Close a file.
*/
void
nfsd_close(struct file *filp)
{
struct dentry *dentry = filp->f_dentry;
struct inode *inode = dentry->d_inode;
if (filp->f_op && filp->f_op->release)
filp->f_op->release(inode, filp);
fops_put(filp->f_op);
if (filp->f_mode & FMODE_WRITE)
put_write_access(inode);
}
/*
* Sync a file
* As this calls fsync (not fdatasync) there is no need for a write_inode
* after it.
*/
void
nfsd_sync(struct file *filp)
{
dprintk("nfsd: sync file %s\n", filp->f_dentry->d_name.name);
down(&filp->f_dentry->d_inode->i_sem);
filp->f_op->fsync(filp, filp->f_dentry, 0);
up(&filp->f_dentry->d_inode->i_sem);
}
void
nfsd_sync_dir(struct dentry *dp)
{
struct inode *inode = dp->d_inode;
int (*fsync) (struct file *, struct dentry *, int);
if (inode->i_fop && (fsync = inode->i_fop->fsync)) {
fsync(NULL, dp, 0);
}
}
/*
* Obtain the readahead parameters for the file
* specified by (dev, ino).
*/
static inline struct raparms *
nfsd_get_raparms(dev_t dev, ino_t ino)
{
struct raparms *ra, **rap, **frap = NULL;
int depth = 0;
for (rap = &raparm_cache; (ra = *rap); rap = &ra->p_next) {
if (ra->p_ino == ino && ra->p_dev == dev)
goto found;
depth++;
if (ra->p_count == 0)
frap = rap;
}
depth = nfsdstats.ra_size*11/10;
if (!frap)
return NULL;
rap = frap;
ra = *frap;
ra->p_dev = dev;
ra->p_ino = ino;
ra->p_reada = 0;
ra->p_ramax = 0;
ra->p_raend = 0;
ra->p_ralen = 0;
ra->p_rawin = 0;
found:
if (rap != &raparm_cache) {
*rap = ra->p_next;
ra->p_next = raparm_cache;
raparm_cache = ra;
}
ra->p_count++;
nfsdstats.ra_depth[depth*10/nfsdstats.ra_size]++;
return ra;
}
/*
* Read data from a file. count must contain the requested read count
* on entry. On return, *count contains the number of bytes actually read.
* N.B. After this call fhp needs an fh_put
*/
int
nfsd_read(struct svc_rqst *rqstp, struct svc_fh *fhp, loff_t offset,
char *buf, unsigned long *count)
{
struct raparms *ra;
mm_segment_t oldfs;
int err;
struct file file;
err = nfsd_open(rqstp, fhp, S_IFREG, MAY_READ, &file);
if (err)
goto out;
err = nfserr_perm;
if (!file.f_op->read)
goto out_close;
#ifdef MSNFS
if ((fhp->fh_export->ex_flags & NFSEXP_MSNFS) &&
(!lock_may_read(file.f_dentry->d_inode, offset, *count)))
goto out_close;
#endif
/* Get readahead parameters */
ra = nfsd_get_raparms(fhp->fh_export->ex_dev, fhp->fh_dentry->d_inode->i_ino);
if (ra) {
file.f_reada = ra->p_reada;
file.f_ramax = ra->p_ramax;
file.f_raend = ra->p_raend;
file.f_ralen = ra->p_ralen;
file.f_rawin = ra->p_rawin;
}
file.f_pos = offset;
oldfs = get_fs(); set_fs(KERNEL_DS);
err = file.f_op->read(&file, buf, *count, &file.f_pos);
set_fs(oldfs);
/* Write back readahead params */
if (ra != NULL) {
dprintk("nfsd: raparms %ld %ld %ld %ld %ld\n",
file.f_reada, file.f_ramax, file.f_raend,
file.f_ralen, file.f_rawin);
ra->p_reada = file.f_reada;
ra->p_ramax = file.f_ramax;
ra->p_raend = file.f_raend;
ra->p_ralen = file.f_ralen;
ra->p_rawin = file.f_rawin;
ra->p_count -= 1;
}
if (err >= 0) {
nfsdstats.io_read += err;
*count = err;
err = 0;
} else
err = nfserrno(err);
out_close:
nfsd_close(&file);
out:
return err;
}
/*
* Write data to a file.
* The stable flag requests synchronous writes.
* N.B. After this call fhp needs an fh_put
*/
int
nfsd_write(struct svc_rqst *rqstp, struct svc_fh *fhp, loff_t offset,
char *buf, unsigned long cnt, int *stablep)
{
struct svc_export *exp;
struct file file;
struct dentry *dentry;
struct inode *inode;
mm_segment_t oldfs;
int err = 0;
int stable = *stablep;
err = nfsd_open(rqstp, fhp, S_IFREG, MAY_WRITE, &file);
if (err)
goto out;
if (!cnt)
goto out_close;
err = nfserr_perm;
if (!file.f_op->write)
goto out_close;
#ifdef MSNFS
if ((fhp->fh_export->ex_flags & NFSEXP_MSNFS) &&
(!lock_may_write(file.f_dentry->d_inode, offset, cnt)))
goto out_close;
#endif
dentry = file.f_dentry;
inode = dentry->d_inode;
exp = fhp->fh_export;
/*
* Request sync writes if
* - the sync export option has been set, or
* - the client requested O_SYNC behavior (NFSv3 feature).
* - The file system doesn't support fsync().
* When gathered writes have been configured for this volume,
* flushing the data to disk is handled separately below.
*/
if (file.f_op->fsync == 0) {/* COMMIT3 cannot work */
stable = 2;
*stablep = 2; /* FILE_SYNC */
}
if (!EX_ISSYNC(exp))
stable = 0;
if (stable && !EX_WGATHER(exp))
file.f_flags |= O_SYNC;
file.f_pos = offset; /* set write offset */
/* Write the data. */
oldfs = get_fs(); set_fs(KERNEL_DS);
err = file.f_op->write(&file, buf, cnt, &file.f_pos);
if (err >= 0)
nfsdstats.io_write += cnt;
set_fs(oldfs);
/* clear setuid/setgid flag after write */
if (err >= 0 && (inode->i_mode & (S_ISUID | S_ISGID))) {
struct iattr ia;
ia.ia_valid = ATTR_MODE;
ia.ia_mode = inode->i_mode & ~(S_ISUID | S_ISGID);
notify_change(dentry, &ia);
}
if (err >= 0 && stable) {
static unsigned long last_ino;
static kdev_t last_dev = NODEV;
/*
* Gathered writes: If another process is currently
* writing to the file, there's a high chance
* this is another nfsd (triggered by a bulk write
* from a client's biod). Rather than syncing the
* file with each write request, we sleep for 10 msec.
*
* I don't know if this roughly approximates
* C. Juszak's idea of gathered writes, but it's a
* nice and simple solution (IMHO), and it seems to
* work:-)
*/
if (EX_WGATHER(exp)) {
if (atomic_read(&inode->i_writecount) > 1
|| (last_ino == inode->i_ino && last_dev == inode->i_dev)) {
dprintk("nfsd: write defer %d\n", current->pid);
set_current_state(TASK_UNINTERRUPTIBLE);
schedule_timeout((HZ+99)/100);
current->state = TASK_RUNNING;
dprintk("nfsd: write resume %d\n", current->pid);
}
if (inode->i_state & I_DIRTY) {
dprintk("nfsd: write sync %d\n", current->pid);
nfsd_sync(&file);
}
#if 0
wake_up(&inode->i_wait);
#endif
}
last_ino = inode->i_ino;
last_dev = inode->i_dev;
}
dprintk("nfsd: write complete err=%d\n", err);
if (err >= 0)
err = 0;
else
err = nfserrno(err);
out_close:
nfsd_close(&file);
out:
return err;
}
#ifdef CONFIG_NFSD_V3
/*
* Commit all pending writes to stable storage.
* Strictly speaking, we could sync just the indicated file region here,
* but there's currently no way we can ask the VFS to do so.
*
* Unfortunately we cannot lock the file to make sure we return full WCC
* data to the client, as locking happens lower down in the filesystem.
*/
int
nfsd_commit(struct svc_rqst *rqstp, struct svc_fh *fhp,
off_t offset, unsigned long count)
{
struct file file;
int err;
if ((err = nfsd_open(rqstp, fhp, S_IFREG, MAY_WRITE, &file)) != 0)
return err;
if (EX_ISSYNC(fhp->fh_export)) {
if (file.f_op && file.f_op->fsync) {
nfsd_sync(&file);
} else {
err = nfserr_notsupp;
}
}
nfsd_close(&file);
return err;
}
#endif /* CONFIG_NFSD_V3 */
/*
* Create a file (regular, directory, device, fifo); UNIX sockets
* not yet implemented.
* If the response fh has been verified, the parent directory should
* already be locked. Note that the parent directory is left locked.
*
* N.B. Every call to nfsd_create needs an fh_put for _both_ fhp and resfhp
*/
int
nfsd_create(struct svc_rqst *rqstp, struct svc_fh *fhp,
char *fname, int flen, struct iattr *iap,
int type, dev_t rdev, struct svc_fh *resfhp)
{
struct dentry *dentry, *dchild;
struct inode *dirp;
int err;
err = nfserr_perm;
if (!flen)
goto out;
err = nfserr_exist;
if (isdotent(fname, flen))
goto out;
err = fh_verify(rqstp, fhp, S_IFDIR, MAY_CREATE);
if (err)
goto out;
dentry = fhp->fh_dentry;
dirp = dentry->d_inode;
err = nfserr_notdir;
if(!dirp->i_op || !dirp->i_op->lookup)
goto out;
/*
* Check whether the response file handle has been verified yet.
* If it has, the parent directory should already be locked.
*/
if (!resfhp->fh_dentry) {
/* called from nfsd_proc_mkdir, or possibly nfsd3_proc_create */
fh_lock(fhp);
dchild = lookup_one_len(fname, dentry, flen);
err = PTR_ERR(dchild);
if (IS_ERR(dchild))
goto out_nfserr;
err = fh_compose(resfhp, fhp->fh_export, dchild, fhp);
if (err)
goto out;
} else {
/* called from nfsd_proc_create */
dchild = resfhp->fh_dentry;
if (!fhp->fh_locked) {
/* not actually possible */
printk(KERN_ERR
"nfsd_create: parent %s/%s not locked!\n",
dentry->d_parent->d_name.name,
dentry->d_name.name);
err = -EIO;
goto out;
}
}
/*
* Make sure the child dentry is still negative ...
*/
err = nfserr_exist;
if (dchild->d_inode) {
dprintk("nfsd_create: dentry %s/%s not negative!\n",
dentry->d_name.name, dchild->d_name.name);
goto out;
}
if (!(iap->ia_valid & ATTR_MODE))
iap->ia_mode = 0;
iap->ia_mode = (iap->ia_mode & S_IALLUGO) | type;
/*
* Get the dir op function pointer.
*/
err = nfserr_perm;
switch (type) {
case S_IFREG:
err = vfs_create(dirp, dchild, iap->ia_mode);
break;
case S_IFDIR:
err = vfs_mkdir(dirp, dchild, iap->ia_mode);
break;
case S_IFCHR:
case S_IFBLK:
case S_IFIFO:
case S_IFSOCK:
err = vfs_mknod(dirp, dchild, iap->ia_mode, rdev);
break;
default:
printk("nfsd: bad file type %o in nfsd_create\n", type);
err = -EINVAL;
}
if (err < 0)
goto out_nfserr;
if (EX_ISSYNC(fhp->fh_export)) {
nfsd_sync_dir(dentry);
write_inode_now(dchild->d_inode, 1);
}
/* Set file attributes. Mode has already been set and
* setting uid/gid works only for root. Irix appears to
* send along the gid when it tries to implement setgid
* directories via NFS.
*/
err = 0;
if ((iap->ia_valid &= ~(ATTR_UID|ATTR_GID|ATTR_MODE)) != 0)
err = nfsd_setattr(rqstp, resfhp, iap, 0, (time_t)0);
/*
* Update the file handle to get the new inode info.
*/
if (!err)
err = fh_update(resfhp);
out:
return err;
out_nfserr:
err = nfserrno(err);
goto out;
}
#ifdef CONFIG_NFSD_V3
/*
* NFSv3 version of nfsd_create
*/
int
nfsd_create_v3(struct svc_rqst *rqstp, struct svc_fh *fhp,
char *fname, int flen, struct iattr *iap,
struct svc_fh *resfhp, int createmode, u32 *verifier)
{
struct dentry *dentry, *dchild;
struct inode *dirp;
int err;
__u32 v_mtime=0, v_atime=0;
int v_mode=0;
err = nfserr_perm;
if (!flen)
goto out;
err = nfserr_exist;
if (isdotent(fname, flen))
goto out;
if (!(iap->ia_valid & ATTR_MODE))
iap->ia_mode = 0;
err = fh_verify(rqstp, fhp, S_IFDIR, MAY_CREATE);
if (err)
goto out;
dentry = fhp->fh_dentry;
dirp = dentry->d_inode;
/* Get all the sanity checks out of the way before
* we lock the parent. */
err = nfserr_notdir;
if(!dirp->i_op || !dirp->i_op->lookup)
goto out;
fh_lock(fhp);
/*
* Compose the response file handle.
*/
dchild = lookup_one_len(fname, dentry, flen);
err = PTR_ERR(dchild);
if (IS_ERR(dchild))
goto out_nfserr;
err = fh_compose(resfhp, fhp->fh_export, dchild, fhp);
if (err)
goto out;
if (createmode == NFS3_CREATE_EXCLUSIVE) {
/* while the verifier would fit in mtime+atime,
* solaris7 gets confused (bugid 4218508) if these have
* the high bit set, so we use the mode as well
*/
v_mtime = verifier[0]&0x7fffffff;
v_atime = verifier[1]&0x7fffffff;
v_mode = S_IFREG
| ((verifier[0]&0x80000000) >> (32-7)) /* u+x */
| ((verifier[1]&0x80000000) >> (32-9)) /* u+r */
;
}
if (dchild->d_inode) {
err = 0;
switch (createmode) {
case NFS3_CREATE_UNCHECKED:
if (! S_ISREG(dchild->d_inode->i_mode))
err = nfserr_exist;
else {
iap->ia_valid &= ATTR_SIZE;
goto set_attr;
}
break;
case NFS3_CREATE_EXCLUSIVE:
if ( dchild->d_inode->i_mtime == v_mtime
&& dchild->d_inode->i_atime == v_atime
&& dchild->d_inode->i_mode == v_mode
&& dchild->d_inode->i_size == 0 )
break;
/* fallthru */
case NFS3_CREATE_GUARDED:
err = nfserr_exist;
}
goto out;
}
err = vfs_create(dirp, dchild, iap->ia_mode);
if (err < 0)
goto out_nfserr;
if (EX_ISSYNC(fhp->fh_export)) {
nfsd_sync_dir(dentry);
/* setattr will sync the child (or not) */
}
/*
* Update the filehandle to get the new inode info.
*/
err = fh_update(resfhp);
if (err)
goto out;
if (createmode == NFS3_CREATE_EXCLUSIVE) {
/* Cram the verifier into atime/mtime/mode */
iap->ia_valid = ATTR_MTIME|ATTR_ATIME
| ATTR_MTIME_SET|ATTR_ATIME_SET
| ATTR_MODE;
iap->ia_mtime = v_mtime;
iap->ia_atime = v_atime;
iap->ia_mode = v_mode;
}
/* Set file attributes.
* Mode has already been set but we might need to reset it
* for CREATE_EXCLUSIVE
* Irix appears to send along the gid when it tries to
* implement setgid directories via NFS. Clear out all that cruft.
*/
set_attr:
if ((iap->ia_valid &= ~(ATTR_UID|ATTR_GID)) != 0)
err = nfsd_setattr(rqstp, resfhp, iap, 0, (time_t)0);
out:
fh_unlock(fhp);
return err;
out_nfserr:
err = nfserrno(err);
goto out;
}
#endif /* CONFIG_NFSD_V3 */
/*
* Read a symlink. On entry, *lenp must contain the maximum path length that
* fits into the buffer. On return, it contains the true length.
* N.B. After this call fhp needs an fh_put
*/
int
nfsd_readlink(struct svc_rqst *rqstp, struct svc_fh *fhp, char *buf, int *lenp)
{
struct dentry *dentry;
struct inode *inode;
mm_segment_t oldfs;
int err;
err = fh_verify(rqstp, fhp, S_IFLNK, MAY_NOP);
if (err)
goto out;
dentry = fhp->fh_dentry;
inode = dentry->d_inode;
err = nfserr_inval;
if (!inode->i_op || !inode->i_op->readlink)
goto out;
UPDATE_ATIME(inode);
/* N.B. Why does this call need a get_fs()??
* Remove the set_fs and watch the fireworks:-) --okir
*/
oldfs = get_fs(); set_fs(KERNEL_DS);
err = inode->i_op->readlink(dentry, buf, *lenp);
set_fs(oldfs);
if (err < 0)
goto out_nfserr;
*lenp = err;
err = 0;
out:
return err;
out_nfserr:
err = nfserrno(err);
goto out;
}
/*
* Create a symlink and look up its inode
* N.B. After this call _both_ fhp and resfhp need an fh_put
*/
int
nfsd_symlink(struct svc_rqst *rqstp, struct svc_fh *fhp,
char *fname, int flen,
char *path, int plen,
struct svc_fh *resfhp,
struct iattr *iap)
{
struct dentry *dentry, *dnew;
int err, cerr;
err = nfserr_noent;
if (!flen || !plen)
goto out;
err = nfserr_exist;
if (isdotent(fname, flen))
goto out;
err = fh_verify(rqstp, fhp, S_IFDIR, MAY_CREATE);
if (err)
goto out;
fh_lock(fhp);
dentry = fhp->fh_dentry;
dnew = lookup_one_len(fname, dentry, flen);
err = PTR_ERR(dnew);
if (IS_ERR(dnew))
goto out_nfserr;
err = vfs_symlink(dentry->d_inode, dnew, path);
if (!err) {
if (EX_ISSYNC(fhp->fh_export))
nfsd_sync_dir(dentry);
if (iap) {
iap->ia_valid &= ATTR_MODE /* ~(ATTR_MODE|ATTR_UID|ATTR_GID)*/;
if (iap->ia_valid) {
iap->ia_valid |= ATTR_CTIME;
iap->ia_mode = (iap->ia_mode&S_IALLUGO)
| S_IFLNK;
err = notify_change(dnew, iap);
if (!err && EX_ISSYNC(fhp->fh_export))
write_inode_now(dentry->d_inode, 1);
}
}
} else
err = nfserrno(err);
fh_unlock(fhp);
/* Compose the fh so the dentry will be freed ... */
cerr = fh_compose(resfhp, fhp->fh_export, dnew, fhp);
if (err==0) err = cerr;
out:
return err;
out_nfserr:
err = nfserrno(err);
goto out;
}
/*
* Create a hardlink
* N.B. After this call _both_ ffhp and tfhp need an fh_put
*/
int
nfsd_link(struct svc_rqst *rqstp, struct svc_fh *ffhp,
char *name, int len, struct svc_fh *tfhp)
{
struct dentry *ddir, *dnew, *dold;
struct inode *dirp, *dest;
int err;
err = fh_verify(rqstp, ffhp, S_IFDIR, MAY_CREATE);
if (err)
goto out;
err = fh_verify(rqstp, tfhp, -S_IFDIR, MAY_NOP);
if (err)
goto out;
err = nfserr_perm;
if (!len)
goto out;
err = nfserr_exist;
if (isdotent(name, len))
goto out;
fh_lock(ffhp);
ddir = ffhp->fh_dentry;
dirp = ddir->d_inode;
dnew = lookup_one_len(name, ddir, len);
err = PTR_ERR(dnew);
if (IS_ERR(dnew))
goto out_nfserr;
dold = tfhp->fh_dentry;
dest = dold->d_inode;
err = vfs_link(dold, dirp, dnew);
if (!err) {
if (EX_ISSYNC(ffhp->fh_export)) {
nfsd_sync_dir(ddir);
write_inode_now(dest, 1);
}
} else {
if (err == -EXDEV && rqstp->rq_vers == 2)
err = nfserr_acces;
else
err = nfserrno(err);
}
fh_unlock(ffhp);
dput(dnew);
out:
return err;
out_nfserr:
err = nfserrno(err);
goto out;
}
/*
* Rename a file
* N.B. After this call _both_ ffhp and tfhp need an fh_put
*/
int
nfsd_rename(struct svc_rqst *rqstp, struct svc_fh *ffhp, char *fname, int flen,
struct svc_fh *tfhp, char *tname, int tlen)
{
struct dentry *fdentry, *tdentry, *odentry, *ndentry;
struct inode *fdir, *tdir;
int err;
err = fh_verify(rqstp, ffhp, S_IFDIR, MAY_REMOVE);
if (err)
goto out;
err = fh_verify(rqstp, tfhp, S_IFDIR, MAY_CREATE);
if (err)
goto out;
fdentry = ffhp->fh_dentry;
fdir = fdentry->d_inode;
tdentry = tfhp->fh_dentry;
tdir = tdentry->d_inode;
err = (rqstp->rq_vers == 2) ? nfserr_acces : nfserr_xdev;
if (fdir->i_dev != tdir->i_dev)
goto out;
err = nfserr_perm;
if (!flen || isdotent(fname, flen) || !tlen || isdotent(tname, tlen))
goto out;
/* cannot use fh_lock as we need deadlock protective ordering
* so do it by hand */
double_down(&tdir->i_sem, &fdir->i_sem);
ffhp->fh_locked = tfhp->fh_locked = 1;
fill_pre_wcc(ffhp);
fill_pre_wcc(tfhp);
odentry = lookup_one_len(fname, fdentry, flen);
err = PTR_ERR(odentry);
if (IS_ERR(odentry))
goto out_nfserr;
err = -ENOENT;
if (!odentry->d_inode)
goto out_dput_old;
ndentry = lookup_one_len(tname, tdentry, tlen);
err = PTR_ERR(ndentry);
if (IS_ERR(ndentry))
goto out_dput_old;
#ifdef MSNFS
if ((ffhp->fh_export->ex_flags & NFSEXP_MSNFS) &&
((atomic_read(&odentry->d_count) > 1)
|| (atomic_read(&ndentry->d_count) > 1))) {
err = nfserr_perm;
} else
#endif
err = vfs_rename(fdir, odentry, tdir, ndentry);
if (!err && EX_ISSYNC(tfhp->fh_export)) {
nfsd_sync_dir(tdentry);
nfsd_sync_dir(fdentry);
}
dput(ndentry);
out_dput_old:
dput(odentry);
out_nfserr:
if (err)
err = nfserrno(err);
/* we cannot reply on fh_unlock on the two filehandles,
* as that would do the wrong thing if the two directories
* were the same, so again we do it by hand
*/
fill_post_wcc(ffhp);
fill_post_wcc(tfhp);
double_up(&tdir->i_sem, &fdir->i_sem);
ffhp->fh_locked = tfhp->fh_locked = 0;
out:
return err;
}
/*
* Unlink a file or directory
* N.B. After this call fhp needs an fh_put
*/
int
nfsd_unlink(struct svc_rqst *rqstp, struct svc_fh *fhp, int type,
char *fname, int flen)
{
struct dentry *dentry, *rdentry;
struct inode *dirp;
int err;
err = nfserr_acces;
if (!flen || isdotent(fname, flen))
goto out;
err = fh_verify(rqstp, fhp, S_IFDIR, MAY_REMOVE);
if (err)
goto out;
fh_lock(fhp);
dentry = fhp->fh_dentry;
dirp = dentry->d_inode;
rdentry = lookup_one_len(fname, dentry, flen);
err = PTR_ERR(rdentry);
if (IS_ERR(rdentry))
goto out_nfserr;
if (!rdentry->d_inode) {
dput(rdentry);
err = nfserr_noent;
goto out;
}
if (type != S_IFDIR) { /* It's UNLINK */
#ifdef MSNFS
if ((fhp->fh_export->ex_flags & NFSEXP_MSNFS) &&
(atomic_read(&rdentry->d_count) > 1)) {
err = nfserr_perm;
} else
#endif
err = vfs_unlink(dirp, rdentry);
} else { /* It's RMDIR */
err = vfs_rmdir(dirp, rdentry);
}
dput(rdentry);
if (err)
goto out_nfserr;
if (EX_ISSYNC(fhp->fh_export))
nfsd_sync_dir(dentry);
out:
return err;
out_nfserr:
err = nfserrno(err);
goto out;
}
/*
* Read entries from a directory.
* The verifier is an NFSv3 thing we ignore for now.
*/
int
nfsd_readdir(struct svc_rqst *rqstp, struct svc_fh *fhp, loff_t offset,
encode_dent_fn func, u32 *buffer, int *countp, u32 *verf)
{
struct inode *inode;
u32 *p;
int oldlen, eof, err;
struct file file;
struct readdir_cd cd;
err = nfsd_open(rqstp, fhp, S_IFDIR, MAY_READ, &file);
if (err)
goto out;
if (offset > ~(u32) 0)
goto out_close;
err = nfserr_notdir;
if (!file.f_op->readdir)
goto out_close;
file.f_pos = offset;
/* Set up the readdir context */
memset(&cd, 0, sizeof(cd));
cd.rqstp = rqstp;
cd.buffer = buffer;
cd.buflen = *countp; /* count of words */
cd.dirfh = fhp;
/*
* Read the directory entries. This silly loop is necessary because
* readdir() is not guaranteed to fill up the entire buffer, but
* may choose to do less.
*/
inode = file.f_dentry->d_inode;
down(&inode->i_sem);
while (1) {
oldlen = cd.buflen;
/*
dprintk("nfsd: f_op->readdir(%x/%ld @ %d) buflen = %d (%d)\n",
file.f_inode->i_dev, file.f_inode->i_ino,
(int) file.f_pos, (int) oldlen, (int) cd.buflen);
*/
err = file.f_op->readdir(&file, &cd, (filldir_t) func);
if (err < 0)
goto out_nfserr;
if (oldlen == cd.buflen)
break;
if (cd.eob)
break;
}
up(&inode->i_sem);
/* If we didn't fill the buffer completely, we're at EOF */
eof = !cd.eob;
if (cd.offset) {
if (rqstp->rq_vers == 3)
(void)xdr_encode_hyper(cd.offset, file.f_pos);
else
*cd.offset = htonl(file.f_pos);
}
p = cd.buffer;
*p++ = 0; /* no more entries */
*p++ = htonl(eof); /* end of directory */
*countp = (caddr_t) p - (caddr_t) buffer;
dprintk("nfsd: readdir result %d bytes, eof %d offset %d\n",
*countp, eof,
cd.offset? ntohl(*cd.offset) : -1);
err = 0;
out_close:
nfsd_close(&file);
out:
return err;
out_nfserr:
up(&inode->i_sem);
err = nfserrno(err);
goto out_close;
}
/*
* Get file system stats
* N.B. After this call fhp needs an fh_put
*/
int
nfsd_statfs(struct svc_rqst *rqstp, struct svc_fh *fhp, struct statfs *stat)
{
int err = fh_verify(rqstp, fhp, 0, MAY_NOP);
if (!err && vfs_statfs(fhp->fh_dentry->d_inode->i_sb,stat))
err = nfserr_io;
return err;
}
/*
* Check for a user's access permissions to this inode.
*/
int
nfsd_permission(struct svc_export *exp, struct dentry *dentry, int acc)
{
struct inode *inode = dentry->d_inode;
int err;
if (acc == MAY_NOP)
return 0;
#if 0
dprintk("nfsd: permission 0x%x%s%s%s%s%s%s%s mode 0%o%s%s%s\n",
acc,
(acc & MAY_READ)? " read" : "",
(acc & MAY_WRITE)? " write" : "",
(acc & MAY_EXEC)? " exec" : "",
(acc & MAY_SATTR)? " sattr" : "",
(acc & MAY_TRUNC)? " trunc" : "",
(acc & MAY_LOCK)? " lock" : "",
(acc & MAY_OWNER_OVERRIDE)? " owneroverride" : "",
inode->i_mode,
IS_IMMUTABLE(inode)? " immut" : "",
IS_APPEND(inode)? " append" : "",
IS_RDONLY(inode)? " ro" : "");
dprintk(" owner %d/%d user %d/%d\n",
inode->i_uid, inode->i_gid, current->fsuid, current->fsgid);
#endif
/* only care about readonly exports for files and
* directories. links don't have meaningful write access,
* and all else is local to the client
*/
if (S_ISREG(inode->i_mode) || S_ISDIR(inode->i_mode))
if (acc & (MAY_WRITE | MAY_SATTR | MAY_TRUNC)) {
if (EX_RDONLY(exp) || IS_RDONLY(inode))
return nfserr_rofs;
if (/* (acc & MAY_WRITE) && */ IS_IMMUTABLE(inode))
return nfserr_perm;
}
if ((acc & MAY_TRUNC) && IS_APPEND(inode))
return nfserr_perm;
if (acc & MAY_LOCK) {
/* If we cannot rely on authentication in NLM requests,
* just allow locks, otherwise require read permission, or
* ownership
*/
if (exp->ex_flags & NFSEXP_NOAUTHNLM)
return 0;
else
acc = MAY_READ | MAY_OWNER_OVERRIDE;
}
/*
* The file owner always gets access permission for accesses that
* would normally be checked at open time. This is to make
* file access work even when the client has done a fchmod(fd, 0).
*
* However, `cp foo bar' should fail nevertheless when bar is
* readonly. A sensible way to do this might be to reject all
* attempts to truncate a read-only file, because a creat() call
* always implies file truncation.
* ... but this isn't really fair. A process may reasonably call
* ftruncate on an open file descriptor on a file with perm 000.
* We must trust the client to do permission checking - using "ACCESS"
* with NFSv3.
*/
if ((acc & MAY_OWNER_OVERRIDE) &&
inode->i_uid == current->fsuid)
return 0;
acc &= ~ MAY_OWNER_OVERRIDE; /* This bit is no longer needed,
and gets in the way later */
err = permission(inode, acc & (MAY_READ|MAY_WRITE|MAY_EXEC));
/* Allow read access to binaries even when mode 111 */
if (err == -EACCES && S_ISREG(inode->i_mode) && acc == MAY_READ)
err = permission(inode, MAY_EXEC);
return err? nfserrno(err) : 0;
}
void
nfsd_racache_shutdown(void)
{
if (!raparm_cache)
return;
dprintk("nfsd: freeing readahead buffers.\n");
kfree(raparml);
raparm_cache = raparml = NULL;
}
/*
* Initialize readahead param cache
*/
int
nfsd_racache_init(int cache_size)
{
int i;
if (raparm_cache)
return 0;
raparml = kmalloc(sizeof(struct raparms) * cache_size, GFP_KERNEL);
if (raparml != NULL) {
dprintk("nfsd: allocating %d readahead buffers.\n",
cache_size);
memset(raparml, 0, sizeof(struct raparms) * cache_size);
for (i = 0; i < cache_size - 1; i++) {
raparml[i].p_next = raparml + i + 1;
}
raparm_cache = raparml;
} else {
printk(KERN_WARNING
"nfsd: Could not allocate memory read-ahead cache.\n");
return -ENOMEM;
}
nfsdstats.ra_size = cache_size;
return 0;
}
|