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author | Linus Torvalds <torvalds@linux-foundation.org> | 2020-02-14 14:46:11 -0800 |
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committer | Linus Torvalds <torvalds@linux-foundation.org> | 2020-02-14 14:46:11 -0800 |
commit | 829e6944699530c47739b5ef091f8137526c1494 (patch) | |
tree | a903b04fa029265c16a282e83ba4028f66c3a64a /fs/nfs/delegation.c | |
parent | Merge tag 'ceph-for-5.6-rc2' of https://github.com/ceph/ceph-client (diff) | |
parent | NFSv4: Ensure the delegation cred is pinned when we call delegreturn (diff) | |
download | linux-dev-829e6944699530c47739b5ef091f8137526c1494.tar.xz linux-dev-829e6944699530c47739b5ef091f8137526c1494.zip |
Merge tag 'nfs-for-5.6-2' of git://git.linux-nfs.org/projects/anna/linux-nfs
Pull NFS client bugfixes from Anna Schumaker:
"The only stable fix this time is the DMA scatter-gather list bug fixed
by Chuck.
The rest fix up races and refcounting issues that have been found
during testing.
Stable fix:
- fix DMA scatter-gather list mapping imbalance
The rest:
- fix directory verifier races
- fix races between open and dentry revalidation
- fix revalidation of dentries with delegations
- fix "cachethis" setting for writes
- fix delegation and delegation cred pinning"
* tag 'nfs-for-5.6-2' of git://git.linux-nfs.org/projects/anna/linux-nfs:
NFSv4: Ensure the delegation cred is pinned when we call delegreturn
NFSv4: Ensure the delegation is pinned in nfs_do_return_delegation()
NFSv4.1 make cachethis=no for writes
xprtrdma: Fix DMA scatter-gather list mapping imbalance
NFSv4: Fix revalidation of dentries with delegations
NFSv4: Fix races between open and dentry revalidation
NFS: Fix up directory verifier races
Diffstat (limited to 'fs/nfs/delegation.c')
-rw-r--r-- | fs/nfs/delegation.c | 50 |
1 files changed, 40 insertions, 10 deletions
diff --git a/fs/nfs/delegation.c b/fs/nfs/delegation.c index 4a841071d8a7..1865322de142 100644 --- a/fs/nfs/delegation.c +++ b/fs/nfs/delegation.c @@ -42,13 +42,27 @@ static void nfs_mark_delegation_revoked(struct nfs_delegation *delegation) if (!test_and_set_bit(NFS_DELEGATION_REVOKED, &delegation->flags)) { delegation->stateid.type = NFS4_INVALID_STATEID_TYPE; atomic_long_dec(&nfs_active_delegations); + if (!test_bit(NFS_DELEGATION_RETURNING, &delegation->flags)) + nfs_clear_verifier_delegated(delegation->inode); } } +static struct nfs_delegation *nfs_get_delegation(struct nfs_delegation *delegation) +{ + refcount_inc(&delegation->refcount); + return delegation; +} + +static void nfs_put_delegation(struct nfs_delegation *delegation) +{ + if (refcount_dec_and_test(&delegation->refcount)) + __nfs_free_delegation(delegation); +} + static void nfs_free_delegation(struct nfs_delegation *delegation) { nfs_mark_delegation_revoked(delegation); - __nfs_free_delegation(delegation); + nfs_put_delegation(delegation); } /** @@ -241,13 +255,18 @@ void nfs_inode_reclaim_delegation(struct inode *inode, const struct cred *cred, static int nfs_do_return_delegation(struct inode *inode, struct nfs_delegation *delegation, int issync) { + const struct cred *cred; int res = 0; - if (!test_bit(NFS_DELEGATION_REVOKED, &delegation->flags)) - res = nfs4_proc_delegreturn(inode, - delegation->cred, + if (!test_bit(NFS_DELEGATION_REVOKED, &delegation->flags)) { + spin_lock(&delegation->lock); + cred = get_cred(delegation->cred); + spin_unlock(&delegation->lock); + res = nfs4_proc_delegreturn(inode, cred, &delegation->stateid, issync); + put_cred(cred); + } return res; } @@ -273,9 +292,13 @@ nfs_start_delegation_return_locked(struct nfs_inode *nfsi) if (delegation == NULL) goto out; spin_lock(&delegation->lock); - if (!test_and_set_bit(NFS_DELEGATION_RETURNING, &delegation->flags)) - ret = delegation; + if (!test_and_set_bit(NFS_DELEGATION_RETURNING, &delegation->flags)) { + /* Refcount matched in nfs_end_delegation_return() */ + ret = nfs_get_delegation(delegation); + } spin_unlock(&delegation->lock); + if (ret) + nfs_clear_verifier_delegated(&nfsi->vfs_inode); out: return ret; } @@ -393,6 +416,7 @@ int nfs_inode_set_delegation(struct inode *inode, const struct cred *cred, if (delegation == NULL) return -ENOMEM; nfs4_stateid_copy(&delegation->stateid, stateid); + refcount_set(&delegation->refcount, 1); delegation->type = type; delegation->pagemod_limit = pagemod_limit; delegation->change_attr = inode_peek_iversion_raw(inode); @@ -492,6 +516,8 @@ static int nfs_end_delegation_return(struct inode *inode, struct nfs_delegation err = nfs_do_return_delegation(inode, delegation, issync); out: + /* Refcount matched in nfs_start_delegation_return_locked() */ + nfs_put_delegation(delegation); return err; } @@ -686,9 +712,12 @@ void nfs4_inode_return_delegation_on_close(struct inode *inode) list_empty(&NFS_I(inode)->open_files) && !test_and_set_bit(NFS_DELEGATION_RETURNING, &delegation->flags)) { clear_bit(NFS_DELEGATION_RETURN_IF_CLOSED, &delegation->flags); - ret = delegation; + /* Refcount matched in nfs_end_delegation_return() */ + ret = nfs_get_delegation(delegation); } spin_unlock(&delegation->lock); + if (ret) + nfs_clear_verifier_delegated(inode); } out: rcu_read_unlock(); @@ -1088,10 +1117,11 @@ restart: delegation = nfs_start_delegation_return_locked(NFS_I(inode)); rcu_read_unlock(); if (delegation != NULL) { - delegation = nfs_detach_delegation(NFS_I(inode), - delegation, server); - if (delegation != NULL) + if (nfs_detach_delegation(NFS_I(inode), delegation, + server) != NULL) nfs_free_delegation(delegation); + /* Match nfs_start_delegation_return_locked */ + nfs_put_delegation(delegation); } iput(inode); nfs_sb_deactive(server->super); |