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| author | Trond Myklebust <trond.myklebust@hammerspace.com> | 2018-09-29 16:00:43 -0400 |
|---|---|---|
| committer | Trond Myklebust <trond.myklebust@hammerspace.com> | 2018-09-30 15:35:18 -0400 |
| commit | 571ed1fd2390f74e4c1f46994f753fb0d29285e4 (patch) | |
| tree | 3fd3225e218bf4e050e402e0aa7f100dca3e19e4 /net/sunrpc/auth_gss | |
| parent | 0c1c19f46efaff427fbf26007954bd090daaf15e (diff) | |
| download | linux-571ed1fd2390f74e4c1f46994f753fb0d29285e4.tar.gz linux-571ed1fd2390f74e4c1f46994f753fb0d29285e4.tar.bz2 linux-571ed1fd2390f74e4c1f46994f753fb0d29285e4.zip | |
SUNRPC: Replace krb5_seq_lock with a lockless scheme
Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>
Diffstat (limited to 'net/sunrpc/auth_gss')
| -rw-r--r-- | net/sunrpc/auth_gss/gss_krb5_seal.c | 37 | ||||
| -rw-r--r-- | net/sunrpc/auth_gss/gss_krb5_wrap.c | 8 |
2 files changed, 28 insertions, 17 deletions
diff --git a/net/sunrpc/auth_gss/gss_krb5_seal.c b/net/sunrpc/auth_gss/gss_krb5_seal.c index eaad9bc7a0bd..0ffb797b92e5 100644 --- a/net/sunrpc/auth_gss/gss_krb5_seal.c +++ b/net/sunrpc/auth_gss/gss_krb5_seal.c @@ -68,8 +68,6 @@ # define RPCDBG_FACILITY RPCDBG_AUTH #endif -DEFINE_SPINLOCK(krb5_seq_lock); - static void * setup_token(struct krb5_ctx *ctx, struct xdr_netobj *token) { @@ -124,6 +122,30 @@ setup_token_v2(struct krb5_ctx *ctx, struct xdr_netobj *token) return krb5_hdr; } +u32 +gss_seq_send_fetch_and_inc(struct krb5_ctx *ctx) +{ + u32 old, seq_send = READ_ONCE(ctx->seq_send); + + do { + old = seq_send; + seq_send = cmpxchg(&ctx->seq_send, old, old + 1); + } while (old != seq_send); + return seq_send; +} + +u64 +gss_seq_send64_fetch_and_inc(struct krb5_ctx *ctx) +{ + u64 old, seq_send = READ_ONCE(ctx->seq_send); + + do { + old = seq_send; + seq_send = cmpxchg(&ctx->seq_send64, old, old + 1); + } while (old != seq_send); + return seq_send; +} + static u32 gss_get_mic_v1(struct krb5_ctx *ctx, struct xdr_buf *text, struct xdr_netobj *token) @@ -154,9 +176,7 @@ gss_get_mic_v1(struct krb5_ctx *ctx, struct xdr_buf *text, memcpy(ptr + GSS_KRB5_TOK_HDR_LEN, md5cksum.data, md5cksum.len); - spin_lock(&krb5_seq_lock); - seq_send = ctx->seq_send++; - spin_unlock(&krb5_seq_lock); + seq_send = gss_seq_send_fetch_and_inc(ctx); if (krb5_make_seq_num(ctx, ctx->seq, ctx->initiate ? 0 : 0xff, seq_send, ptr + GSS_KRB5_TOK_HDR_LEN, ptr + 8)) @@ -174,7 +194,6 @@ gss_get_mic_v2(struct krb5_ctx *ctx, struct xdr_buf *text, .data = cksumdata}; void *krb5_hdr; s32 now; - u64 seq_send; u8 *cksumkey; unsigned int cksum_usage; __be64 seq_send_be64; @@ -185,11 +204,7 @@ gss_get_mic_v2(struct krb5_ctx *ctx, struct xdr_buf *text, /* Set up the sequence number. Now 64-bits in clear * text and w/o direction indicator */ - spin_lock(&krb5_seq_lock); - seq_send = ctx->seq_send64++; - spin_unlock(&krb5_seq_lock); - - seq_send_be64 = cpu_to_be64(seq_send); + seq_send_be64 = cpu_to_be64(gss_seq_send64_fetch_and_inc(ctx)); memcpy(krb5_hdr + 8, (char *) &seq_send_be64, 8); if (ctx->initiate) { diff --git a/net/sunrpc/auth_gss/gss_krb5_wrap.c b/net/sunrpc/auth_gss/gss_krb5_wrap.c index 39a2e672900b..41cb294cd071 100644 --- a/net/sunrpc/auth_gss/gss_krb5_wrap.c +++ b/net/sunrpc/auth_gss/gss_krb5_wrap.c @@ -228,9 +228,7 @@ gss_wrap_kerberos_v1(struct krb5_ctx *kctx, int offset, memcpy(ptr + GSS_KRB5_TOK_HDR_LEN, md5cksum.data, md5cksum.len); - spin_lock(&krb5_seq_lock); - seq_send = kctx->seq_send++; - spin_unlock(&krb5_seq_lock); + seq_send = gss_seq_send_fetch_and_inc(kctx); /* XXX would probably be more efficient to compute checksum * and encrypt at the same time: */ @@ -477,9 +475,7 @@ gss_wrap_kerberos_v2(struct krb5_ctx *kctx, u32 offset, *be16ptr++ = 0; be64ptr = (__be64 *)be16ptr; - spin_lock(&krb5_seq_lock); - *be64ptr = cpu_to_be64(kctx->seq_send64++); - spin_unlock(&krb5_seq_lock); + *be64ptr = cpu_to_be64(gss_seq_send64_fetch_and_inc(kctx)); err = (*kctx->gk5e->encrypt_v2)(kctx, offset, buf, pages); if (err) |