From: Bernd Schubert Subject: [PATCH 5 4/4] nfsd: vfs_llseek() with 32 or 64 bit offsets (hashes) Date: Mon, 09 Jan 2012 14:21:58 +0100 Message-ID: <20120109132158.2616029.30467.stgit@localhost.localdomain> References: <20120109132137.2616029.76288.stgit@localhost.localdomain> Mime-Version: 1.0 Content-Type: text/plain; charset="utf-8" Content-Transfer-Encoding: 7bit Cc: linux-fsdevel@vger.kernel.org, yong.fan@whamcloud.com, "J. Bruce Fields" , sandeen@redhat.com, adilger@whamcloud.com To: linux-nfs@vger.kernel.org, linux-ext4@vger.kernel.org Return-path: In-Reply-To: <20120109132137.2616029.76288.stgit@localhost.localdomain> Sender: linux-fsdevel-owner@vger.kernel.org List-Id: linux-ext4.vger.kernel.org Use 32-bit or 64-bit llseek() hashes for directory offsets depending on the NFS version. NFSv2 gets 32-bit hashes only. NOTE: This patch got rather complex as Christoph asked to set the filp->f_mode flag in the open call or immediatly after dentry_open() in nfsd_open() to avoid races. Personally I still do not see a reason for that and in my opinion FMODE_32BITHASH/FMODE_64BITHASH flags could be set nfsd_readdir(), as it follows directly after nfsd_open() without a chance of races. Signed-off-by: Bernd Schubert Acked-by: J. Bruce Fields --- fs/nfsd/vfs.c | 15 +++++++++++++-- fs/nfsd/vfs.h | 2 ++ 2 files changed, 15 insertions(+), 2 deletions(-) diff --git a/fs/nfsd/vfs.c b/fs/nfsd/vfs.c index 20fa252..f162dc3 100644 --- a/fs/nfsd/vfs.c +++ b/fs/nfsd/vfs.c @@ -785,9 +785,15 @@ nfsd_open(struct svc_rqst *rqstp, struct svc_fh *fhp, umode_t type, flags, current_cred()); if (IS_ERR(*filp)) host_err = PTR_ERR(*filp); - else + else { host_err = ima_file_check(*filp, may_flags); + if (may_flags & NFSD_MAY_64BIT_COOKIE) + (*filp)->f_mode |= FMODE_64BITHASH; + else + (*filp)->f_mode |= FMODE_32BITHASH; + } + out_nfserr: err = nfserrno(host_err); out: @@ -2011,8 +2017,13 @@ nfsd_readdir(struct svc_rqst *rqstp, struct svc_fh *fhp, loff_t *offsetp, __be32 err; struct file *file; loff_t offset = *offsetp; + int may_flags = NFSD_MAY_READ; + + /* NFSv2 only supports 32 bit cookies */ + if (rqstp->rq_vers > 2) + may_flags |= NFSD_MAY_64BIT_COOKIE; - err = nfsd_open(rqstp, fhp, S_IFDIR, NFSD_MAY_READ, &file); + err = nfsd_open(rqstp, fhp, S_IFDIR, may_flags, &file); if (err) goto out; diff --git a/fs/nfsd/vfs.h b/fs/nfsd/vfs.h index 1dcd238..ec0611b 100644 --- a/fs/nfsd/vfs.h +++ b/fs/nfsd/vfs.h @@ -27,6 +27,8 @@ #define NFSD_MAY_BYPASS_GSS 0x400 #define NFSD_MAY_READ_IF_EXEC 0x800 +#define NFSD_MAY_64BIT_COOKIE 0x1000 /* 64 bit readdir cookies for >= NFSv3 */ + #define NFSD_MAY_CREATE (NFSD_MAY_EXEC|NFSD_MAY_WRITE) #define NFSD_MAY_REMOVE (NFSD_MAY_EXEC|NFSD_MAY_WRITE|NFSD_MAY_TRUNC)