Return-Path: Received: from frankvm.xs4all.nl ([83.163.148.79]:46139 "EHLO janus.localdomain" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S1754944Ab1G1Sok (ORCPT ); Thu, 28 Jul 2011 14:44:40 -0400 From: Frank van Maarseveen To: linux-nfs@vger.kernel.org Subject: [PATCH 2/2] Support a per-mount NLM grace period. Date: Thu, 28 Jul 2011 20:44:20 +0200 Message-Id: <1311878660-24482-3-git-send-email-frankvm@frankvm.com> In-Reply-To: <1311878660-24482-1-git-send-email-frankvm@frankvm.com> References: <1311878660-24482-1-git-send-email-frankvm@frankvm.com> Sender: linux-nfs-owner@vger.kernel.org List-ID: Content-Type: text/plain MIME-Version: 1.0 This implements /proc/fs/nfsd/relock_filesystem, complementing /proc/fs/nfsd/unlock_filesystem using an identical syntax. When a mountpoint pathname is written to the first then an NLM grace period will start for files referring to its super block. Signed-off-by: Frank van Maarseveen --- fs/lockd/grace.c | 86 +++++++++++++++++++++++++++++++++++++++++++++++++-- fs/lockd/svc.c | 1 + fs/lockd/svclock.c | 8 ++-- fs/lockd/svcshare.c | 4 +- fs/nfsd/nfs4proc.c | 12 ++++--- fs/nfsd/nfs4state.c | 14 ++++---- fs/nfsd/nfsctl.c | 26 +++++++++++++-- include/linux/fs.h | 4 ++- 8 files changed, 130 insertions(+), 25 deletions(-) diff --git a/fs/lockd/grace.c b/fs/lockd/grace.c index 183cc1f..6ddb806 100644 --- a/fs/lockd/grace.c +++ b/fs/lockd/grace.c @@ -4,8 +4,18 @@ #include #include +#include +#include +#include + +struct sb_in_grace { + struct list_head sbg_link; + struct vfsmount *sbg_mnt; + u64 sbg_timeout; +}; static LIST_HEAD(grace_list); +static LIST_HEAD(sb_grace_list); static DEFINE_SPINLOCK(grace_lock); /** @@ -46,14 +56,84 @@ void locks_end_grace(struct lock_manager *lm) EXPORT_SYMBOL_GPL(locks_end_grace); /** + * locks_start_sb_grace + * @path: reference to superblock of FS to enter grace. + * + * This function is a filesystem specific version of locks_start_grace() + */ +int locks_start_sb_grace(struct path *path) +{ + struct sb_in_grace *sbg; + + sbg = kzalloc(sizeof(*sbg), GFP_KERNEL); + if (!sbg) + return -ENOMEM; + mntget(path->mnt); + sbg->sbg_mnt = path->mnt; + sbg->sbg_timeout = get_jiffies_64() + nlmsvc_grace_period(); + spin_lock(&grace_lock); + list_add_tail(&sbg->sbg_link, &sb_grace_list); + spin_unlock(&grace_lock); + return 0; +} +EXPORT_SYMBOL_GPL(locks_start_sb_grace); + +/** + * locks_end_sb_grace + * @path: reference to superblock of FS to leave grace. + * + * This function is a filesystem specific version of locks_end_grace() + * When @path is NULL then all filesystem specific grace periods end. + */ +void locks_end_sb_grace(struct path *path) +{ + struct sb_in_grace *sbg, *next; + struct super_block *sb = path ? path->mnt->mnt_sb : NULL; + + spin_lock(&grace_lock); + list_for_each_entry_safe(sbg, next, &sb_grace_list, sbg_link) { + if (!sb || sb == sbg->sbg_mnt->mnt_sb) { + list_del(&sbg->sbg_link); + mntput(sbg->sbg_mnt); + kfree(sbg); + } + } + spin_unlock(&grace_lock); +} +EXPORT_SYMBOL_GPL(locks_end_sb_grace); + +/** * locks_in_grace + * @sb: super block for checking filesystem specific grace time. * * Lock managers call this function to determine when it is OK for them * to answer ordinary lock requests, and when they should accept only - * lock reclaims. + * lock reclaims. @sb can be NULL to test for a global grace period. */ -int locks_in_grace(void) +int locks_in_grace(struct super_block *sb) { - return !list_empty(&grace_list); + struct sb_in_grace *sbg, *next; + int in_grace; + u64 now; + + if (!list_empty(&grace_list)) + return true; + in_grace = false; + now = get_jiffies_64(); + spin_lock(&grace_lock); + list_for_each_entry_safe(sbg, next, &sb_grace_list, sbg_link) { + if (time_after64(now, sbg->sbg_timeout)) { + list_del(&sbg->sbg_link); + mntput(sbg->sbg_mnt); + kfree(sbg); + continue; + } + if (sb == sbg->sbg_mnt->mnt_sb) { + in_grace = true; + break; + } + } + spin_unlock(&grace_lock); + return in_grace; } EXPORT_SYMBOL_GPL(locks_in_grace); diff --git a/fs/lockd/svc.c b/fs/lockd/svc.c index 0efbbfc..9c53971 100644 --- a/fs/lockd/svc.c +++ b/fs/lockd/svc.c @@ -186,6 +186,7 @@ lockd(void *vrqstp) flush_signals(current); cancel_delayed_work_sync(&grace_period_end); locks_end_grace(&lockd_manager); + locks_end_sb_grace(NULL); if (nlmsvc_ops) nlmsvc_invalidate_all(); nlm_shutdown_hosts(); diff --git a/fs/lockd/svclock.c b/fs/lockd/svclock.c index ab62c57..95c85d7 100644 --- a/fs/lockd/svclock.c +++ b/fs/lockd/svclock.c @@ -419,11 +419,11 @@ nlmsvc_lock(struct svc_rqst *rqstp, struct nlm_file *file, goto out; } - if (locks_in_grace() && !reclaim) { + if (locks_in_grace(file->f_file->f_path.dentry->d_sb) && !reclaim) { ret = nlm_lck_denied_grace_period; goto out; } - if (reclaim && !locks_in_grace()) { + if (reclaim && !locks_in_grace(file->f_file->f_path.dentry->d_sb)) { ret = nlm_lck_denied_grace_period; goto out; } @@ -531,7 +531,7 @@ nlmsvc_testlock(struct svc_rqst *rqstp, struct nlm_file *file, goto out; } - if (locks_in_grace()) { + if (locks_in_grace(file->f_file->f_path.dentry->d_sb)) { ret = nlm_lck_denied_grace_period; goto out; } @@ -617,7 +617,7 @@ nlmsvc_cancel_blocked(struct nlm_file *file, struct nlm_lock *lock) (long long)lock->fl.fl_start, (long long)lock->fl.fl_end); - if (locks_in_grace()) + if (locks_in_grace(file->f_file->f_path.dentry->d_sb)) return nlm_lck_denied_grace_period; mutex_lock(&file->f_mutex); diff --git a/fs/lockd/svcshare.c b/fs/lockd/svcshare.c index ccad267..10c7415 100644 --- a/fs/lockd/svcshare.c +++ b/fs/lockd/svcshare.c @@ -32,7 +32,7 @@ nlmsvc_share_file(struct nlm_host *host, struct nlm_file *file, u8 *ohdata; /* Don't accept new share requests during grace period */ - if (locks_in_grace() && !argp->reclaim) + if (locks_in_grace(file->f_file->f_path.dentry->d_sb) && !argp->reclaim) return nlm_lck_denied_grace_period; for (share = file->f_shares; share; share = share->s_next) { @@ -76,7 +76,7 @@ nlmsvc_unshare_file(struct nlm_host *host, struct nlm_file *file, struct xdr_netobj *oh = &argp->lock.oh; /* Don't accept unshare requests during grace period */ - if (locks_in_grace()) + if (locks_in_grace(file->f_file->f_path.dentry->d_sb)) return nlm_lck_denied_grace_period; for (shpp = &file->f_shares; (share = *shpp) != NULL; diff --git a/fs/nfsd/nfs4proc.c b/fs/nfsd/nfs4proc.c index e248b9e..fa325df 100644 --- a/fs/nfsd/nfs4proc.c +++ b/fs/nfsd/nfs4proc.c @@ -330,10 +330,12 @@ nfsd4_open(struct svc_rqst *rqstp, struct nfsd4_compound_state *cstate, /* Openowner is now set, so sequence id will get bumped. Now we need * these checks before we do any creates: */ status = nfserr_grace; - if (locks_in_grace() && open->op_claim_type != NFS4_OPEN_CLAIM_PREVIOUS) + if (locks_in_grace(cstate->current_fh.fh_dentry->d_sb) + && open->op_claim_type != NFS4_OPEN_CLAIM_PREVIOUS) goto out; status = nfserr_no_grace; - if (open->op_claim_type == NFS4_OPEN_CLAIM_PREVIOUS && !locks_in_grace()) + if (open->op_claim_type == NFS4_OPEN_CLAIM_PREVIOUS + && !locks_in_grace(cstate->current_fh.fh_dentry->d_sb)) goto out; switch (open->op_claim_type) { @@ -715,7 +717,7 @@ nfsd4_remove(struct svc_rqst *rqstp, struct nfsd4_compound_state *cstate, { __be32 status; - if (locks_in_grace()) + if (locks_in_grace(cstate->current_fh.fh_dentry->d_sb)) return nfserr_grace; status = nfsd_unlink(rqstp, &cstate->current_fh, 0, remove->rm_name, remove->rm_namelen); @@ -736,8 +738,8 @@ nfsd4_rename(struct svc_rqst *rqstp, struct nfsd4_compound_state *cstate, if (!cstate->save_fh.fh_dentry) return status; - if (locks_in_grace() && !(cstate->save_fh.fh_export->ex_flags - & NFSEXP_NOSUBTREECHECK)) + if (locks_in_grace(cstate->save_fh.fh_dentry->d_sb) + && !(cstate->save_fh.fh_export->ex_flags & NFSEXP_NOSUBTREECHECK)) return nfserr_grace; status = nfsd_rename(rqstp, &cstate->save_fh, rename->rn_sname, rename->rn_snamelen, &cstate->current_fh, diff --git a/fs/nfsd/nfs4state.c b/fs/nfsd/nfs4state.c index 741e03a..5f3f3cc 100644 --- a/fs/nfsd/nfs4state.c +++ b/fs/nfsd/nfs4state.c @@ -2779,7 +2779,7 @@ nfs4_open_delegation(struct svc_fh *fh, struct nfsd4_open *open, struct nfs4_sta case NFS4_OPEN_CLAIM_NULL: /* Let's not give out any delegations till everyone's * had the chance to reclaim theirs.... */ - if (locks_in_grace()) + if (locks_in_grace(fh->fh_dentry->d_sb)) goto out; if (!cb_up || !sop->so_confirmed) goto out; @@ -2972,7 +2972,7 @@ nfs4_laundromat(void) nfs4_lock_state(); dprintk("NFSD: laundromat service - starting\n"); - if (locks_in_grace()) + if (locks_in_grace(NULL)) nfsd4_end_grace(); INIT_LIST_HEAD(&reaplist); spin_lock(&client_lock); @@ -3117,7 +3117,7 @@ check_special_stateids(svc_fh *current_fh, stateid_t *stateid, int flags) { if (ONE_STATEID(stateid) && (flags & RD_STATE)) return nfs_ok; - else if (locks_in_grace()) { + else if (locks_in_grace(current_fh->fh_dentry->d_sb)) { /* Answer in remaining cases depends on existence of * conflicting state; so we must wait out the grace period. */ return nfserr_grace; @@ -3136,7 +3136,7 @@ check_special_stateids(svc_fh *current_fh, stateid_t *stateid, int flags) static inline int grace_disallows_io(struct inode *inode) { - return locks_in_grace() && mandatory_lock(inode); + return locks_in_grace(inode->i_sb) && mandatory_lock(inode); } static int check_stateid_generation(stateid_t *in, stateid_t *ref, int flags) @@ -4058,10 +4058,10 @@ nfsd4_lock(struct svc_rqst *rqstp, struct nfsd4_compound_state *cstate, /* lock->lk_replay_owner and lock_stp have been created or found */ status = nfserr_grace; - if (locks_in_grace() && !lock->lk_reclaim) + if (locks_in_grace(cstate->current_fh.fh_dentry->d_sb) && !lock->lk_reclaim) goto out; status = nfserr_no_grace; - if (lock->lk_reclaim && !locks_in_grace()) + if (lock->lk_reclaim && !locks_in_grace(cstate->current_fh.fh_dentry->d_sb)) goto out; locks_init_lock(&file_lock); @@ -4166,7 +4166,7 @@ nfsd4_lockt(struct svc_rqst *rqstp, struct nfsd4_compound_state *cstate, int error; __be32 status; - if (locks_in_grace()) + if (locks_in_grace(cstate->current_fh.fh_dentry->d_sb)) return nfserr_grace; if (check_lock_length(lockt->lt_offset, lockt->lt_length)) diff --git a/fs/nfsd/nfsctl.c b/fs/nfsd/nfsctl.c index c771614..af992ef 100644 --- a/fs/nfsd/nfsctl.c +++ b/fs/nfsd/nfsctl.c @@ -29,6 +29,7 @@ enum { NFSD_Fh, NFSD_FO_UnlockIP, NFSD_FO_UnlockFS, + NFSD_FO_RelockFS, NFSD_Threads, NFSD_Pool_Threads, NFSD_Pool_Stats, @@ -53,6 +54,7 @@ enum { static ssize_t write_filehandle(struct file *file, char *buf, size_t size); static ssize_t write_unlock_ip(struct file *file, char *buf, size_t size); static ssize_t write_unlock_fs(struct file *file, char *buf, size_t size); +static ssize_t write_relock_fs(struct file *file, char *buf, size_t size); static ssize_t write_threads(struct file *file, char *buf, size_t size); static ssize_t write_pool_threads(struct file *file, char *buf, size_t size); static ssize_t write_versions(struct file *file, char *buf, size_t size); @@ -68,6 +70,7 @@ static ssize_t (*write_op[])(struct file *, char *, size_t) = { [NFSD_Fh] = write_filehandle, [NFSD_FO_UnlockIP] = write_unlock_ip, [NFSD_FO_UnlockFS] = write_unlock_fs, + [NFSD_FO_RelockFS] = write_relock_fs, [NFSD_Threads] = write_threads, [NFSD_Pool_Threads] = write_pool_threads, [NFSD_Versions] = write_versions, @@ -229,7 +232,7 @@ static ssize_t write_unlock_ip(struct file *file, char *buf, size_t size) } /** - * write_unlock_fs - Release all locks on a local file system + * start_stop_fs_locking - Drop all locks or enter grace period for a FS * * Experimental. * @@ -242,7 +245,7 @@ static ssize_t write_unlock_ip(struct file *file, char *buf, size_t size) * returns one if one or more locks were not released * On error: return code is negative errno value */ -static ssize_t write_unlock_fs(struct file *file, char *buf, size_t size) +static ssize_t start_stop_fs_locking(struct file *file, char *buf, size_t size, int start) { struct path path; char *fo_path; @@ -272,12 +275,27 @@ static ssize_t write_unlock_fs(struct file *file, char *buf, size_t size) * 2. Is that directory a mount point, or * 3. Is that directory the root of an exported file system? */ - error = nlmsvc_unlock_all_by_sb(path.mnt->mnt_sb); + if (start) + error = locks_start_sb_grace(&path); + else { + locks_end_sb_grace(&path); // drop sb reference + error = nlmsvc_unlock_all_by_sb(path.mnt->mnt_sb); + } path_put(&path); return error; } +static ssize_t write_unlock_fs(struct file *file, char *buf, size_t size) +{ + return start_stop_fs_locking(file, buf, size, false); +} + +static ssize_t write_relock_fs(struct file *file, char *buf, size_t size) +{ + return start_stop_fs_locking(file, buf, size, true); +} + /** * write_filehandle - Get a variable-length NFS file handle by path * @@ -1070,6 +1088,8 @@ static int nfsd_fill_super(struct super_block * sb, void * data, int silent) &transaction_ops, S_IWUSR|S_IRUSR}, [NFSD_FO_UnlockFS] = {"unlock_filesystem", &transaction_ops, S_IWUSR|S_IRUSR}, + [NFSD_FO_RelockFS] = {"relock_filesystem", + &transaction_ops, S_IWUSR|S_IRUSR}, [NFSD_Fh] = {"filehandle", &transaction_ops, S_IWUSR|S_IRUSR}, [NFSD_Threads] = {"threads", &transaction_ops, S_IWUSR|S_IRUSR}, [NFSD_Pool_Threads] = {"pool_threads", &transaction_ops, S_IWUSR|S_IRUSR}, diff --git a/include/linux/fs.h b/include/linux/fs.h index f23bcb7..752f6b8 100644 --- a/include/linux/fs.h +++ b/include/linux/fs.h @@ -1086,7 +1086,9 @@ struct lock_manager { void locks_start_grace(struct lock_manager *); void locks_end_grace(struct lock_manager *); -int locks_in_grace(void); +int locks_start_sb_grace(struct path *); +void locks_end_sb_grace(struct path *); +int locks_in_grace(struct super_block *); /* that will die - we need it for nfs_lock_info */ #include -- 1.7.4.4