Return-Path: Received: from mail-yk0-f172.google.com ([209.85.160.172]:35031 "EHLO mail-yk0-f172.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751495AbbHEVNv (ORCPT ); Wed, 5 Aug 2015 17:13:51 -0400 Received: by ykcq64 with SMTP id q64so41666507ykc.2 for ; Wed, 05 Aug 2015 14:13:50 -0700 (PDT) From: Jeff Layton To: bfields@fieldses.org Cc: linux-nfs@vger.kernel.org Subject: [PATCH v2 10/18] nfsd: handle NFSD_MAY_NOT_BREAK_LEASE in open file cache Date: Wed, 5 Aug 2015 17:13:28 -0400 Message-Id: <1438809216-4846-11-git-send-email-jeff.layton@primarydata.com> In-Reply-To: <1438809216-4846-1-git-send-email-jeff.layton@primarydata.com> References: <1438264341-18048-1-git-send-email-jeff.layton@primarydata.com> <1438809216-4846-1-git-send-email-jeff.layton@primarydata.com> Sender: linux-nfs-owner@vger.kernel.org List-ID: The NFSD_MAY_NOT_BREAK_LEASE flag needs special handling. If we open a file in order to do (e.g.) a COMMIT then we don't want to break any leases, but subsequent READ/WRITE operations must break the leases. If we construct a new cache entry with a set of may flags that have NFSD_MAY_NOT_BREAK_LEASE set, then set flags in the cache entry that indicate that subsequent users of this file must break leases before using it if they do not have NFSD_MAY_NOT_BREAK_LEASE set. Note that because NFSD_MAY_READ opens do not break read leases, we must track what sort of lease breaks have been done. If we're breaking leases for read, then we still need to do a lease break for write if it's a R/W open and a writer comes along. Lease breaks for write however imply a read lease break so we can clear both flags in that event. Signed-off-by: Jeff Layton --- fs/nfsd/filecache.c | 40 ++++++++++++++++++++++++++++++++++++---- fs/nfsd/filecache.h | 2 ++ fs/nfsd/vfs.c | 3 ++- fs/nfsd/vfs.h | 1 + 4 files changed, 41 insertions(+), 5 deletions(-) diff --git a/fs/nfsd/filecache.c b/fs/nfsd/filecache.c index 084e56726318..0adcc674441d 100644 --- a/fs/nfsd/filecache.c +++ b/fs/nfsd/filecache.c @@ -68,6 +68,12 @@ nfsd_file_alloc(struct knfsd_fh *fh, unsigned int may, unsigned int hashval) nf->nf_hashval = hashval; atomic_set(&nf->nf_ref, 1); nf->nf_may = NFSD_FILE_MAY_MASK & may; + if (may & NFSD_MAY_NOT_BREAK_LEASE) { + if (may & NFSD_MAY_WRITE) + __set_bit(NFSD_FILE_BREAK_WRITE, &nf->nf_flags); + if (may & NFSD_MAY_READ) + __set_bit(NFSD_FILE_BREAK_READ, &nf->nf_flags); + } } return nf; } @@ -269,8 +275,6 @@ nfsd_file_acquire(struct svc_rqst *rqstp, struct svc_fh *fhp, struct knfsd_fh *fh = &fhp->fh_handle; unsigned int hashval = file_hashval(fh); - /* Mask off any extraneous bits */ - may_flags &= NFSD_FILE_MAY_MASK; retry: rcu_read_lock(); nf = nfsd_file_find_locked(fh, may_flags, hashval); @@ -311,7 +315,7 @@ wait_for_construction: * MAY flags are equal. Otherwise, we put the reference and try * again. */ - if (may_flags != nf->nf_may) { + if ((may_flags & NFSD_FILE_MAY_MASK) != nf->nf_may) { nfsd_file_put(nf); goto retry; } @@ -319,6 +323,18 @@ wait_for_construction: /* try to take over construction for this file */ if (test_and_set_bit(NFSD_FILE_PENDING, &nf->nf_flags)) goto wait_for_construction; + + /* sync up the BREAK_* flags with our may_flags */ + if (may_flags & NFSD_MAY_NOT_BREAK_LEASE) { + if (may_flags & NFSD_MAY_WRITE) + set_bit(NFSD_FILE_BREAK_WRITE, &nf->nf_flags); + if (may_flags & NFSD_MAY_READ) + set_bit(NFSD_FILE_BREAK_READ, &nf->nf_flags); + } else { + clear_bit(NFSD_FILE_BREAK_WRITE, &nf->nf_flags); + clear_bit(NFSD_FILE_BREAK_READ, &nf->nf_flags); + } + goto open_file; } @@ -330,7 +346,23 @@ wait_for_construction: status = fh_verify(rqstp, fhp, S_IFREG, may_flags); if (status == nfs_ok) status = nfsd_permission(rqstp, fhp->fh_export, fhp->fh_dentry, - may_flags|NFSD_MAY_OWNER_OVERRIDE); + may_flags|NFSD_MAY_OWNER_OVERRIDE); + + if (status == nfs_ok && !(may_flags & NFSD_MAY_NOT_BREAK_LEASE)) { + bool write = (may_flags & NFSD_MAY_WRITE); + + if (test_bit(NFSD_FILE_BREAK_READ, &nf->nf_flags) || + (test_bit(NFSD_FILE_BREAK_WRITE, &nf->nf_flags) && write)) { + status = nfserrno(nfsd_open_break_lease( + file_inode(nf->nf_file), may_flags)); + if (status == nfs_ok) { + clear_bit(NFSD_FILE_BREAK_READ, &nf->nf_flags); + if (write) + clear_bit(NFSD_FILE_BREAK_WRITE, + &nf->nf_flags); + } + } + } out: if (status == nfs_ok) *pnf = nf; diff --git a/fs/nfsd/filecache.h b/fs/nfsd/filecache.h index 98976f71caa8..b8a59d615729 100644 --- a/fs/nfsd/filecache.h +++ b/fs/nfsd/filecache.h @@ -31,6 +31,8 @@ struct nfsd_file { unsigned long nf_time; #define NFSD_FILE_HASHED (0) #define NFSD_FILE_PENDING (1) +#define NFSD_FILE_BREAK_READ (2) +#define NFSD_FILE_BREAK_WRITE (3) unsigned long nf_flags; struct knfsd_fh nf_handle; unsigned int nf_hashval; diff --git a/fs/nfsd/vfs.c b/fs/nfsd/vfs.c index fd688c86af66..79a881589ca7 100644 --- a/fs/nfsd/vfs.c +++ b/fs/nfsd/vfs.c @@ -618,7 +618,8 @@ nfsd_access(struct svc_rqst *rqstp, struct svc_fh *fhp, u32 *access, u32 *suppor } #endif /* CONFIG_NFSD_V3 */ -static int nfsd_open_break_lease(struct inode *inode, int access) +int +nfsd_open_break_lease(struct inode *inode, int access) { unsigned int mode; diff --git a/fs/nfsd/vfs.h b/fs/nfsd/vfs.h index 78b5527cba93..a3ec59830297 100644 --- a/fs/nfsd/vfs.h +++ b/fs/nfsd/vfs.h @@ -69,6 +69,7 @@ __be32 do_nfsd_create(struct svc_rqst *, struct svc_fh *, __be32 nfsd_commit(struct svc_rqst *, struct svc_fh *, loff_t, unsigned long); #endif /* CONFIG_NFSD_V3 */ +int nfsd_open_break_lease(struct inode *, int); __be32 nfsd_open(struct svc_rqst *, struct svc_fh *, umode_t, int, struct file **); struct raparms; -- 2.4.3