v3: rebased on 3.5-rc3 kernel v2: dl_recall_lru list is used for delegations collect because it's modified both in unhash_delegation() and nfsd_break_one_deleg().
This patch adds recall_lock hold to nfsd_forget_delegations() to protect nfsd_process_n_delegations() call. Also, looks like it would be better to collect delegations to some local on-stack list, and then unhash collected list. This split allows to simplify locking, because delegation traversing is protected by recall_lock, when delegation unhash is protected by client_mutex. Signed-off-by: Stanislav Kinsbursky <[email protected]> --- fs/nfsd/nfs4state.c | 21 +++++++++++++++++---- 1 files changed, 17 insertions(+), 4 deletions(-) diff --git a/fs/nfsd/nfs4state.c b/fs/nfsd/nfs4state.c index 59b9efc..33eccee 100644 --- a/fs/nfsd/nfs4state.c +++ b/fs/nfsd/nfs4state.c @@ -4579,7 +4579,7 @@ void nfsd_forget_openowners(u64 num) printk(KERN_INFO "NFSD: Forgot %d open owners", count); } -int nfsd_process_n_delegations(u64 num, void (*deleg_func)(struct nfs4_delegation *)) +int nfsd_process_n_delegations(u64 num, struct list_head *list) { int i, count = 0; struct nfs4_file *fp, *fnext; @@ -4588,7 +4588,7 @@ int nfsd_process_n_delegations(u64 num, void (*deleg_func)(struct nfs4_delegatio for (i = 0; i < FILE_HASH_SIZE; i++) { list_for_each_entry_safe(fp, fnext, &file_hashtbl[i], fi_hash) { list_for_each_entry_safe(dp, dnext, &fp->fi_delegations, dl_perfile) { - deleg_func(dp); + list_move(&dp->dl_recall_lru, list); if (++count == num) return count; } @@ -4601,9 +4601,16 @@ int nfsd_process_n_delegations(u64 num, void (*deleg_func)(struct nfs4_delegatio void nfsd_forget_delegations(u64 num) { unsigned int count; + LIST_HEAD(victims); + struct nfs4_delegation *dp, *dnext; + + spin_lock(&recall_lock); + count = nfsd_process_n_delegations(num, &victims); + spin_unlock(&recall_lock); nfs4_lock_state(); - count = nfsd_process_n_delegations(num, unhash_delegation); + list_for_each_entry_safe(dp, dnext, &victims, dl_recall_lru) + unhash_delegation(dp); nfs4_unlock_state(); printk(KERN_INFO "NFSD: Forgot %d delegations", count); @@ -4612,10 +4619,16 @@ void nfsd_forget_delegations(u64 num) void nfsd_recall_delegations(u64 num) { unsigned int count; + LIST_HEAD(victims); + struct nfs4_delegation *dp, *dnext; nfs4_lock_state(); spin_lock(&recall_lock); - count = nfsd_process_n_delegations(num, nfsd_break_one_deleg); + count = nfsd_process_n_delegations(num, &victims); + list_for_each_entry_safe(dp, dnext, &victims, dl_recall_lru) { + list_del(&dp->dl_recall_lru); + nfsd_break_one_deleg(dp); + } spin_unlock(&recall_lock); nfs4_unlock_state(); _______________________________________________ Devel mailing list [email protected] https://openvz.org/mailman/listinfo/devel
