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| author | Stanislav Kinsbursky <skinsbursky@parallels.com> | 2012-05-25 18:38:50 +0400 |
|---|---|---|
| committer | J. Bruce Fields <bfields@redhat.com> | 2012-07-25 09:18:27 -0400 |
| commit | a6d88f293ecd1b7444e128777f4a893e7a998852 (patch) | |
| tree | cb8e65d7b24192bc8cdbe2afa4aad506c0e99db7 /fs/nfsd/nfs4state.c | |
| parent | 5559b50acdcdcad7e362882d3261bf934c9436f6 (diff) | |
| download | linux-stable-a6d88f293ecd1b7444e128777f4a893e7a998852.tar.gz linux-stable-a6d88f293ecd1b7444e128777f4a893e7a998852.tar.bz2 linux-stable-a6d88f293ecd1b7444e128777f4a893e7a998852.zip | |
NFSd: fix locking in nfsd_forget_delegations()
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 <skinsbursky@parallels.com>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
Diffstat (limited to 'fs/nfsd/nfs4state.c')
| -rw-r--r-- | fs/nfsd/nfs4state.c | 23 |
1 files changed, 17 insertions, 6 deletions
diff --git a/fs/nfsd/nfs4state.c b/fs/nfsd/nfs4state.c index fe96015fbfcb..d10ad8bc47aa 100644 --- a/fs/nfsd/nfs4state.c +++ b/fs/nfsd/nfs4state.c @@ -4575,7 +4575,7 @@ 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; @@ -4584,7 +4584,7 @@ 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; } @@ -4597,9 +4597,16 @@ 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); @@ -4608,12 +4615,16 @@ 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(); printk(KERN_INFO "NFSD: Recalled %d delegations", count); } |