diff options
Diffstat (limited to 'fs/nfsd/vfs.c')
| -rw-r--r-- | fs/nfsd/vfs.c | 1859 |
1 files changed, 1859 insertions, 0 deletions
diff --git a/fs/nfsd/vfs.c b/fs/nfsd/vfs.c new file mode 100644 index 000000000000..e3e9d217236e --- /dev/null +++ b/fs/nfsd/vfs.c @@ -0,0 +1,1859 @@ +#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 exported, 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> + * Zerocpy NFS support (C) 2002 Hirokazu Takahashi <taka@valinux.co.jp> + */ + +#include <linux/config.h> +#include <linux/string.h> +#include <linux/time.h> +#include <linux/errno.h> +#include <linux/fs.h> +#include <linux/file.h> +#include <linux/mount.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/pagemap.h> +#include <linux/in.h> +#include <linux/module.h> +#include <linux/namei.h> +#include <linux/vfs.h> +#include <linux/delay.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 <linux/dnotify.h> +#ifdef CONFIG_NFSD_V4 +#include <linux/posix_acl.h> +#include <linux/posix_acl_xattr.h> +#include <linux/xattr_acl.h> +#include <linux/xattr.h> +#include <linux/nfs4.h> +#include <linux/nfs4_acl.h> +#include <linux/nfsd_idmap.h> +#include <linux/security.h> +#endif /* CONFIG_NFSD_V4 */ + +#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; + int p_set; + struct file_ra_state p_ra; +}; + +static struct raparms * raparml; +static struct raparms * raparm_cache; + +/* + * Called from nfsd_lookup and encode_dirent. Check if we have crossed + * a mount point. + * Returns -EAGAIN leaving *dpp and *expp unchanged, + * or nfs_ok having possibly changed *dpp and *expp + */ +int +nfsd_cross_mnt(struct svc_rqst *rqstp, struct dentry **dpp, + struct svc_export **expp) +{ + struct svc_export *exp = *expp, *exp2 = NULL; + struct dentry *dentry = *dpp; + struct vfsmount *mnt = mntget(exp->ex_mnt); + struct dentry *mounts = dget(dentry); + int err = nfs_ok; + + while (follow_down(&mnt,&mounts)&&d_mountpoint(mounts)); + + exp2 = exp_get_by_name(exp->ex_client, mnt, mounts, &rqstp->rq_chandle); + if (IS_ERR(exp2)) { + err = PTR_ERR(exp2); + dput(mounts); + mntput(mnt); + goto out; + } + if (exp2 && ((exp->ex_flags & NFSEXP_CROSSMOUNT) || EX_NOHIDE(exp2))) { + /* successfully crossed mount point */ + exp_put(exp); + *expp = exp2; + dput(dentry); + *dpp = mounts; + } else { + if (exp2) exp_put(exp2); + dput(mounts); + } + mntput(mnt); +out: + return err; +} + +/* + * 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_NOHIDE, 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) + return err; + + dparent = fhp->fh_dentry; + exp = fhp->fh_export; + exp_get(exp); + + err = nfserr_acces; + + /* Lookup the name, but don't follow links */ + if (isdotent(name, len)) { + if (len==1) + dentry = dget(dparent); + else if (dparent != exp->ex_dentry) { + dentry = dget_parent(dparent); + } else if (!EX_NOHIDE(exp)) + dentry = dget(dparent); /* .. == . just like at / */ + else { + /* checking mountpoint crossing is very different when stepping up */ + struct svc_export *exp2 = NULL; + struct dentry *dp; + struct vfsmount *mnt = mntget(exp->ex_mnt); + dentry = dget(dparent); + while(dentry == mnt->mnt_root && follow_up(&mnt, &dentry)) + ; + dp = dget_parent(dentry); + dput(dentry); + dentry = dp; + + exp2 = exp_parent(exp->ex_client, mnt, dentry, + &rqstp->rq_chandle); + if (IS_ERR(exp2)) { + err = PTR_ERR(exp2); + dput(dentry); + mntput(mnt); + goto out_nfserr; + } + if (!exp2) { + dput(dentry); + dentry = dget(dparent); + } else { + exp_put(exp); + exp = exp2; + } + mntput(mnt); + } + } 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)) { + if ((err = nfsd_cross_mnt(rqstp, &dentry, &exp))) { + dput(dentry); + goto out_nfserr; + } + } + } + /* + * 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; + dput(dentry); +out: + exp_put(exp); + 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; + + /* NFSv2 does not differentiate between "set-[ac]time-to-now" + * which only requires access, and "set-[ac]time-to-X" which + * requires ownership. + * So if it looks like it might be "set both to the same time which + * is close to now", and if inode_change_ok fails, then we + * convert to "set to now" instead of "set to explicit time" + * + * We only call inode_change_ok as the last test as technically + * it is not an interface that we should be using. It is only + * valid if the filesystem does not define it's own i_op->setattr. + */ +#define BOTH_TIME_SET (ATTR_ATIME_SET | ATTR_MTIME_SET) +#define MAX_TOUCH_TIME_ERROR (30*60) + if ((iap->ia_valid & BOTH_TIME_SET) == BOTH_TIME_SET + && iap->ia_mtime.tv_sec == iap->ia_atime.tv_sec + ) { + /* Looks probable. Now just make sure time is in the right ballpark. + * Solaris, at least, doesn't seem to care what the time request is. + * We require it be within 30 minutes of now. + */ + time_t delta = iap->ia_atime.tv_sec - get_seconds(); + if (delta<0) delta = -delta; + if (delta < MAX_TOUCH_TIME_ERROR && + inode_change_ok(inode, iap) != 0) { + /* 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; + } + } + + /* 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 = break_lease(inode, FMODE_WRITE | O_NONBLOCK); + if (err == -EWOULDBLOCK) + err = -ETIMEDOUT; + if (err) /* ENOMEM or EWOULDBLOCK */ + goto out_nfserr; + + err = get_write_access(inode); + if (err) + goto out_nfserr; + + size_change = 1; + 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) && iap->ia_uid != inode->i_uid) + iap->ia_valid |= ATTR_KILL_SUID; + if ((iap->ia_valid & ATTR_GID) && iap->ia_gid != inode->i_gid) + iap->ia_valid |= ATTR_KILL_SGID; + + /* Change the attributes. */ + + iap->ia_valid |= ATTR_CTIME; + + err = nfserr_notsync; + if (!check_guard || guardtime == inode->i_ctime.tv_sec) { + fh_lock(fhp); + err = notify_change(dentry, iap); + err = nfserrno(err); + fh_unlock(fhp); + } + if (size_change) + 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; +} + +#if defined(CONFIG_NFSD_V4) + +static int +set_nfsv4_acl_one(struct dentry *dentry, struct posix_acl *pacl, char *key) +{ + int len; + size_t buflen; + char *buf = NULL; + int error = 0; + struct inode *inode = dentry->d_inode; + + buflen = posix_acl_xattr_size(pacl->a_count); + buf = kmalloc(buflen, GFP_KERNEL); + error = -ENOMEM; + if (buf == NULL) + goto out; + + len = posix_acl_to_xattr(pacl, buf, buflen); + if (len < 0) { + error = len; + goto out; + } + + error = -EOPNOTSUPP; + if (inode->i_op && inode->i_op->setxattr) { + down(&inode->i_sem); + security_inode_setxattr(dentry, key, buf, len, 0); + error = inode->i_op->setxattr(dentry, key, buf, len, 0); + if (!error) + security_inode_post_setxattr(dentry, key, buf, len, 0); + up(&inode->i_sem); + } +out: + kfree(buf); + return error; +} + +int +nfsd4_set_nfs4_acl(struct svc_rqst *rqstp, struct svc_fh *fhp, + struct nfs4_acl *acl) +{ + int error; + struct dentry *dentry; + struct inode *inode; + struct posix_acl *pacl = NULL, *dpacl = NULL; + unsigned int flags = 0; + + /* Get inode */ + error = fh_verify(rqstp, fhp, 0 /* S_IFREG */, MAY_SATTR); + if (error) + goto out; + + dentry = fhp->fh_dentry; + inode = dentry->d_inode; + if (S_ISDIR(inode->i_mode)) + flags = NFS4_ACL_DIR; + + error = nfs4_acl_nfsv4_to_posix(acl, &pacl, &dpacl, flags); + if (error == -EINVAL) { + error = nfserr_attrnotsupp; + goto out; + } else if (error < 0) + goto out_nfserr; + + if (pacl) { + error = set_nfsv4_acl_one(dentry, pacl, XATTR_NAME_ACL_ACCESS); + if (error < 0) + goto out_nfserr; + } + + if (dpacl) { + error = set_nfsv4_acl_one(dentry, dpacl, XATTR_NAME_ACL_DEFAULT); + if (error < 0) + goto out_nfserr; + } + + error = nfs_ok; + +out: + posix_acl_release(pacl); + posix_acl_release(dpacl); + return (error); +out_nfserr: + error = nfserrno(error); + goto out; +} + +static struct posix_acl * +_get_posix_acl(struct dentry *dentry, char *key) +{ + struct inode *inode = dentry->d_inode; + char *buf = NULL; + int buflen, error = 0; + struct posix_acl *pacl = NULL; + + error = -EOPNOTSUPP; + if (inode->i_op == NULL) + goto out_err; + if (inode->i_op->getxattr == NULL) + goto out_err; + + error = security_inode_getxattr(dentry, key); + if (error) + goto out_err; + + buflen = inode->i_op->getxattr(dentry, key, NULL, 0); + if (buflen <= 0) { + error = buflen < 0 ? buflen : -ENODATA; + goto out_err; + } + + buf = kmalloc(buflen, GFP_KERNEL); + if (buf == NULL) { + error = -ENOMEM; + goto out_err; + } + + error = inode->i_op->getxattr(dentry, key, buf, buflen); + if (error < 0) + goto out_err; + + pacl = posix_acl_from_xattr(buf, buflen); + out: + kfree(buf); + return pacl; + out_err: + pacl = ERR_PTR(error); + goto out; +} + +int +nfsd4_get_nfs4_acl(struct svc_rqst *rqstp, struct dentry *dentry, struct nfs4_acl **acl) +{ + struct inode *inode = dentry->d_inode; + int error = 0; + struct posix_acl *pacl = NULL, *dpacl = NULL; + unsigned int flags = 0; + + pacl = _get_posix_acl(dentry, XATTR_NAME_ACL_ACCESS); + if (IS_ERR(pacl) && PTR_ERR(pacl) == -ENODATA) + pacl = posix_acl_from_mode(inode->i_mode, GFP_KERNEL); + if (IS_ERR(pacl)) { + error = PTR_ERR(pacl); + pacl = NULL; + goto out; + } + + if (S_ISDIR(inode->i_mode)) { + dpacl = _get_posix_acl(dentry, XATTR_NAME_ACL_DEFAULT); + if (IS_ERR(dpacl) && PTR_ERR(dpacl) == -ENODATA) + dpacl = NULL; + else if (IS_ERR(dpacl)) { + error = PTR_ERR(dpacl); + dpacl = NULL; + goto out; + } + flags = NFS4_ACL_DIR; + } + + *acl = nfs4_acl_posix_to_nfsv4(pacl, dpacl, flags); + if (IS_ERR(*acl)) { + error = PTR_ERR(*acl); + *acl = NULL; + } + out: + posix_acl_release(pacl); + posix_acl_release(dpacl); + return error; +} + +#endif /* defined(CONFIG_NFS_V4) */ + +#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, and we make sure to ignore read-only + * filesystem checks + */ + { NFS3_ACCESS_READ, MAY_READ }, + { NFS3_ACCESS_EXECUTE, MAY_EXEC }, + { NFS3_ACCESS_MODIFY, MAY_WRITE|MAY_LOCAL_ACCESS }, + { NFS3_ACCESS_EXTEND, MAY_WRITE|MAY_LOCAL_ACCESS }, + + { 0, 0 } +}; + +int +nfsd_access(struct svc_rqst *rqstp, struct svc_fh *fhp, u32 *access, u32 *supported) +{ + struct accessmap *map; + struct svc_export *export; + struct dentry *dentry; + u32 query, result = 0, sresult = 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; + + sresult |= map->access; + + 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; + if (supported) + *supported = sresult; + + 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 flags = O_RDONLY|O_LARGEFILE, 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 write access to files with the append-only bit set + * or any access when mandatory locking enabled + */ + err = nfserr_perm; + if (IS_APPEND(inode) && (access & MAY_WRITE)) + goto out; + if (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 = break_lease(inode, O_NONBLOCK | ((access & MAY_WRITE) ? FMODE_WRITE : 0)); + if (err == -EWOULDBLOCK) + err = -ETIMEDOUT; + if (err) /* NOMEM or WOULDBLOCK */ + goto out_nfserr; + + if (access & MAY_WRITE) { + flags = O_WRONLY|O_LARGEFILE; + + DQUOT_INIT(inode); + } + *filp = dentry_open(dget(dentry), mntget(fhp->fh_export->ex_mnt), flags); + if (IS_ERR(*filp)) + err = PTR_ERR(*filp); +out_nfserr: + if (err) + err = nfserrno(err); +out: + return err; +} + +/* + * Close a file. + */ +void +nfsd_close(struct file *filp) +{ + fput(filp); +} + +/* + * Sync a file + * As this calls fsync (not fdatasync) there is no need for a write_inode + * after it. + */ +static inline void nfsd_dosync(struct file *filp, struct dentry *dp, + struct file_operations *fop) +{ + struct inode *inode = dp->d_inode; + int (*fsync) (struct file *, struct dentry *, int); + + filemap_fdatawrite(inode->i_mapping); + if (fop && (fsync = fop->fsync)) + fsync(filp, dp, 0); + filemap_fdatawait(inode->i_mapping); +} + + +static void +nfsd_sync(struct file *filp) +{ + struct inode *inode = filp->f_dentry->d_inode; + dprintk("nfsd: sync file %s\n", filp->f_dentry->d_name.name); + down(&inode->i_sem); + nfsd_dosync(filp, filp->f_dentry, filp->f_op); + up(&inode->i_sem); +} + +static void +nfsd_sync_dir(struct dentry *dp) +{ + nfsd_dosync(NULL, dp, dp->d_inode->i_fop); +} + +/* + * Obtain the readahead parameters for the file + * specified by (dev, ino). + */ +static DEFINE_SPINLOCK(ra_lock); + +static inline struct raparms * +nfsd_get_raparms(dev_t dev, ino_t ino) +{ + struct raparms *ra, **rap, **frap = NULL; + int depth = 0; + + spin_lock(&ra_lock); + 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) { + spin_unlock(&ra_lock); + return NULL; + } + rap = frap; + ra = *frap; + ra->p_dev = dev; + ra->p_ino = ino; + ra->p_set = 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]++; + spin_unlock(&ra_lock); + return ra; +} + +/* + * Grab and keep cached pages assosiated with a file in the svc_rqst + * so that they can be passed to the netowork sendmsg/sendpage routines + * directrly. They will be released after the sending has completed. + */ +static int +nfsd_read_actor(read_descriptor_t *desc, struct page *page, unsigned long offset , unsigned long size) +{ + unsigned long count = desc->count; + struct svc_rqst *rqstp = desc->arg.data; + + if (size > count) + size = count; + + if (rqstp->rq_res.page_len == 0) { + get_page(page); + rqstp->rq_respages[rqstp->rq_resused++] = page; + rqstp->rq_res.page_base = offset; + rqstp->rq_res.page_len = size; + } else if (page != rqstp->rq_respages[rqstp->rq_resused-1]) { + get_page(page); + rqstp->rq_respages[rqstp->rq_resused++] = page; + rqstp->rq_res.page_len += size; + } else { + rqstp->rq_res.page_len += size; + } + + desc->count = count - size; + desc->written += size; + return size; +} + +static inline int +nfsd_vfs_read(struct svc_rqst *rqstp, struct svc_fh *fhp, struct file *file, + loff_t offset, struct kvec *vec, int vlen, unsigned long *count) +{ + struct inode *inode; + struct raparms *ra; + mm_segment_t oldfs; + int err; + + err = nfserr_perm; + inode = file->f_dentry->d_inode; +#ifdef MSNFS + if ((fhp->fh_export->ex_flags & NFSEXP_MSNFS) && + (!lock_may_read(inode, offset, *count))) + goto out; +#endif + + /* Get readahead parameters */ + ra = nfsd_get_raparms(inode->i_sb->s_dev, inode->i_ino); + + if (ra && ra->p_set) + file->f_ra = ra->p_ra; + + if (file->f_op->sendfile) { + svc_pushback_unused_pages(rqstp); + err = file->f_op->sendfile(file, &offset, *count, + nfsd_read_actor, rqstp); + } else { + oldfs = get_fs(); + set_fs(KERNEL_DS); + err = vfs_readv(file, (struct iovec __user *)vec, vlen, &offset); + set_fs(oldfs); + } + + /* Write back readahead params */ + if (ra) { + spin_lock(&ra_lock); + ra->p_ra = file->f_ra; + ra->p_set = 1; + ra->p_count--; + spin_unlock(&ra_lock); + } + + if (err >= 0) { + nfsdstats.io_read += err; + *count = err; + err = 0; + dnotify_parent(file->f_dentry, DN_ACCESS); + } else + err = nfserrno(err); +out: + return err; +} + +static inline int +nfsd_vfs_write(struct svc_rqst *rqstp, struct svc_fh *fhp, struct file *file, + loff_t offset, struct kvec *vec, int vlen, + unsigned long cnt, int *stablep) +{ + struct svc_export *exp; + struct dentry *dentry; + struct inode *inode; + mm_segment_t oldfs; + int err = 0; + int stable = *stablep; + + err = nfserr_perm; + +#ifdef MSNFS + if ((fhp->fh_export->ex_flags & NFSEXP_MSNFS) && + (!lock_may_write(file->f_dentry->d_inode, offset, cnt))) + goto out; +#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; + + /* Write the data. */ + oldfs = get_fs(); set_fs(KERNEL_DS); + err = vfs_writev(file, (struct iovec __user *)vec, vlen, &offset); + set_fs(oldfs); + if (err >= 0) { + nfsdstats.io_write += cnt; + dnotify_parent(file->f_dentry, DN_MODIFY); + } + + /* clear setuid/setgid flag after write */ + if (err >= 0 && (inode->i_mode & (S_ISUID | S_ISGID))) { + struct iattr ia; + ia.ia_valid = ATTR_KILL_SUID | ATTR_KILL_SGID; + + down(&inode->i_sem); + notify_change(dentry, &ia); + up(&inode->i_sem); + } + + if (err >= 0 && stable) { + static ino_t last_ino; + static dev_t last_dev; + + /* + * 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_sb->s_dev)) { + dprintk("nfsd: write defer %d\n", current->pid); + msleep(10); + 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_sb->s_dev; + } + + dprintk("nfsd: write complete err=%d\n", err); + if (err >= 0) + err = 0; + else + err = nfserrno(err); +out: + return err; +} + +/* + * 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, struct file *file, + loff_t offset, struct kvec *vec, int vlen, + unsigned long *count) +{ + int err; + + if (file) { + err = nfsd_permission(fhp->fh_export, fhp->fh_dentry, + MAY_READ|MAY_OWNER_OVERRIDE); + if (err) + goto out; + err = nfsd_vfs_read(rqstp, fhp, file, offset, vec, vlen, count); + } else { + err = nfsd_open(rqstp, fhp, S_IFREG, MAY_READ, &file); + if (err) + goto out; + err = nfsd_vfs_read(rqstp, fhp, file, offset, vec, vlen, count); + 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, struct file *file, + loff_t offset, struct kvec *vec, int vlen, unsigned long cnt, + int *stablep) +{ + int err = 0; + + if (file) { + err = nfsd_permission(fhp->fh_export, fhp->fh_dentry, + MAY_WRITE|MAY_OWNER_OVERRIDE); + if (err) + goto out; + err = nfsd_vfs_write(rqstp, fhp, file, offset, vec, vlen, cnt, + stablep); + } else { + err = nfsd_open(rqstp, fhp, S_IFREG, MAY_WRITE, &file); + if (err) + goto out; + + if (cnt) + err = nfsd_vfs_write(rqstp, fhp, file, offset, vec, vlen, + cnt, stablep); + 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, + loff_t offset, unsigned long count) +{ + struct file *file; + int err; + + if ((u64)count > ~(u64)offset) + return nfserr_inval; + + 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 = NULL; + 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 = dget(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, NULL); + 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: + if (dchild && !IS_ERR(dchild)) + dput(dchild); + 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, + int *truncp) +{ + struct dentry *dentry, *dchild = NULL; + 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 if (truncp) { + /* in nfsv4, we need to treat this case a little + * differently. we don't want to truncate the + * file now; this would be wrong if the OPEN + * fails for some other reason. furthermore, + * if the size is nonzero, we should ignore it + * according to spec! + */ + *truncp = (iap->ia_valid & ATTR_SIZE) && !iap->ia_size; + } + else { + iap->ia_valid &= ATTR_SIZE; + goto set_attr; + } + break; + case NFS3_CREATE_EXCLUSIVE: + if ( dchild->d_inode->i_mtime.tv_sec == v_mtime + && dchild->d_inode->i_atime.tv_sec == 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, NULL); + 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; + /* XXX someone who knows this better please fix it for nsec */ + iap->ia_mtime.tv_sec = v_mtime; + iap->ia_atime.tv_sec = v_atime; + iap->ia_mtime.tv_nsec = 0; + iap->ia_atime.tv_nsec = 0; + 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); + if (dchild && !IS_ERR(dchild)) + dput(dchild); + 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; + + touch_atime(fhp->fh_export->ex_mnt, dentry); + /* 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; + umode_t mode; + + 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; + + mode = S_IALLUGO; + /* Only the MODE ATTRibute is even vaguely meaningful */ + if (iap && (iap->ia_valid & ATTR_MODE)) + mode = iap->ia_mode & S_IALLUGO; + + if (unlikely(path[plen] != 0)) { + char *path_alloced = kmalloc(plen+1, GFP_KERNEL); + if (path_alloced == NULL) + err = -ENOMEM; + else { + strncpy(path_alloced, path, plen); + path_alloced[plen] = 0; + err = vfs_symlink(dentry->d_inode, dnew, path_alloced, mode); + kfree(path_alloced); + } + } else + err = vfs_symlink(dentry->d_inode, dnew, path, mode); + + if (!err) { + if (EX_ISSYNC(fhp->fh_export)) + nfsd_sync_dir(dentry); + } else + err = nfserrno(err); + fh_unlock(fhp); + + cerr = fh_compose(resfhp, fhp->fh_export, dnew, fhp); + dput(dnew); + 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, *trap; + 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_sb != tdir->i_sb) + 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 */ + trap = lock_rename(tdentry, fdentry); + 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; + err = -EINVAL; + if (odentry == trap) + goto out_dput_old; + + ndentry = lookup_one_len(tname, tdentry, tlen); + err = PTR_ERR(ndentry); + if (IS_ERR(ndentry)) + goto out_dput_old; + err = -ENOTEMPTY; + if (ndentry == trap) + goto out_dput_new; + +#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); + } + + out_dput_new: + 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); + unlock_rename(tdentry, fdentry); + 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) + type = rdentry->d_inode->i_mode & S_IFMT; + + 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 NFSv3/4 verifier we ignore for now. + */ +int +nfsd_readdir(struct svc_rqst *rqstp, struct svc_fh *fhp, loff_t *offsetp, + struct readdir_cd *cdp, encode_dent_fn func) +{ + int err; + struct file *file; + loff_t offset = *offsetp; + + err = nfsd_open(rqstp, fhp, S_IFDIR, MAY_READ, &file); + if (err) + goto out; + + offset = vfs_llseek(file, offset, 0); + if (offset < 0) { + err = nfserrno((int)offset); + goto out_close; + } + + /* + * 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. + */ + + do { + cdp->err = nfserr_eof; /* will be cleared on successful read */ + err = vfs_readdir(file, (filldir_t) func, cdp); + } while (err >=0 && cdp->err == nfs_ok); + if (err) + err = nfserrno(err); + else + err = cdp->err; + *offsetp = vfs_llseek(file, 0, 1); + + if (err == nfserr_eof || err == nfserr_toosmall) + err = nfs_ok; /* can still be found in ->err */ +out_close: + nfsd_close(file); +out: + return err; +} + +/* + * 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 kstatfs *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 + + /* Normally we reject any write/sattr etc access on a read-only file + * system. But if it is IRIX doing check on write-access for a + * device special file, we ignore rofs. + */ + if (!(acc & MAY_LOCAL_ACCESS)) + 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; + + err = permission(inode, acc & (MAY_READ|MAY_WRITE|MAY_EXEC), NULL); + + /* Allow read access to binaries even when mode 111 */ + if (err == -EACCES && S_ISREG(inode->i_mode) && + acc == (MAY_READ | MAY_OWNER_OVERRIDE)) + err = permission(inode, MAY_EXEC, NULL); + + 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; +} |