diff options
Diffstat (limited to 'fs/nfsd/vfs.c')
-rw-r--r-- | fs/nfsd/vfs.c | 97 |
1 files changed, 60 insertions, 37 deletions
diff --git a/fs/nfsd/vfs.c b/fs/nfsd/vfs.c index ca13236..26c6fdb 100644 --- a/fs/nfsd/vfs.c +++ b/fs/nfsd/vfs.c @@ -332,6 +332,37 @@ nfsd_sanitize_attrs(struct inode *inode, struct iattr *iap) } } +static __be32 +nfsd_get_write_access(struct svc_rqst *rqstp, struct svc_fh *fhp, + struct iattr *iap) +{ + struct inode *inode = d_inode(fhp->fh_dentry); + int host_err; + + if (iap->ia_size < inode->i_size) { + __be32 err; + + err = nfsd_permission(rqstp, fhp->fh_export, fhp->fh_dentry, + NFSD_MAY_TRUNC | NFSD_MAY_OWNER_OVERRIDE); + if (err) + return err; + } + + host_err = get_write_access(inode); + if (host_err) + goto out_nfserrno; + + host_err = locks_verify_truncate(inode, NULL, iap->ia_size); + if (host_err) + goto out_put_write_access; + return 0; + +out_put_write_access: + put_write_access(inode); +out_nfserrno: + return nfserrno(host_err); +} + /* * Set various file attributes. After this call fhp needs an fh_put. */ @@ -346,6 +377,7 @@ nfsd_setattr(struct svc_rqst *rqstp, struct svc_fh *fhp, struct iattr *iap, __be32 err; int host_err; bool get_write_count; + int size_change = 0; if (iap->ia_valid & (ATTR_ATIME | ATTR_MTIME | ATTR_SIZE)) accmode |= NFSD_MAY_WRITE|NFSD_MAY_OWNER_OVERRIDE; @@ -358,11 +390,11 @@ nfsd_setattr(struct svc_rqst *rqstp, struct svc_fh *fhp, struct iattr *iap, /* Get inode */ err = fh_verify(rqstp, fhp, ftype, accmode); if (err) - return err; + goto out; if (get_write_count) { host_err = fh_want_write(fhp); if (host_err) - goto out_host_err; + return nfserrno(host_err); } dentry = fhp->fh_dentry; @@ -373,59 +405,50 @@ nfsd_setattr(struct svc_rqst *rqstp, struct svc_fh *fhp, struct iattr *iap, iap->ia_valid &= ~ATTR_MODE; if (!iap->ia_valid) - return 0; + goto out; nfsd_sanitize_attrs(inode, iap); - if (check_guard && guardtime != inode->i_ctime.tv_sec) - return nfserr_notsync; - /* * The size case is special, it changes the file in addition to the - * attributes, and file systems don't expect it to be mixed with - * "random" attribute changes. We thus split out the size change - * into a separate call for vfs_truncate, and do the rest as a - * a separate setattr call. + * attributes. */ if (iap->ia_valid & ATTR_SIZE) { - struct path path = { - .mnt = fhp->fh_export->ex_path.mnt, - .dentry = dentry, - }; - bool implicit_mtime = false; + err = nfsd_get_write_access(rqstp, fhp, iap); + if (err) + goto out; + size_change = 1; /* - * vfs_truncate implicity updates the mtime IFF the file size - * actually changes. Avoid the additional seattr call below if - * the only other attribute that the client sends is the mtime. + * RFC5661, Section 18.30.4: + * Changing the size of a file with SETATTR indirectly + * changes the time_modify and change attributes. + * + * (and similar for the older RFCs) */ - if (iap->ia_size != i_size_read(inode) && - ((iap->ia_valid & ~(ATTR_SIZE | ATTR_MTIME)) == 0)) - implicit_mtime = true; - - host_err = vfs_truncate(&path, iap->ia_size); - if (host_err) - goto out_host_err; - - iap->ia_valid &= ~ATTR_SIZE; - if (implicit_mtime) - iap->ia_valid &= ~ATTR_MTIME; - if (!iap->ia_valid) - goto done; + if (iap->ia_size != i_size_read(inode)) + iap->ia_valid |= ATTR_MTIME; } iap->ia_valid |= ATTR_CTIME; + if (check_guard && guardtime != inode->i_ctime.tv_sec) { + err = nfserr_notsync; + goto out_put_write_access; + } + fh_lock(fhp); host_err = notify_change(dentry, iap, NULL); fh_unlock(fhp); - if (host_err) - goto out_host_err; + err = nfserrno(host_err); -done: - host_err = commit_metadata(fhp); -out_host_err: - return nfserrno(host_err); +out_put_write_access: + if (size_change) + put_write_access(inode); + if (!err) + err = nfserrno(commit_metadata(fhp)); +out: + return err; } #if defined(CONFIG_NFSD_V4) |