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authorLinus Torvalds <torvalds@linux-foundation.org>2017-05-02 16:40:27 -0700
committerLinus Torvalds <torvalds@linux-foundation.org>2017-05-02 16:40:27 -0700
commit8d65b08debc7e62b2c6032d7fe7389d895b92cbc (patch)
tree0c3141b60c3a03cc32742b5750c5e763b9dae489 /drivers/net/ethernet/netronome/nfp/nfpcore/nfp_mutex.c
parent5a0387a8a8efb90ae7fea1e2e5c62de3efa74691 (diff)
parent5d15af6778b8e4ed1fd41b040283af278e7a9a72 (diff)
Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net-next
Pull networking updates from David Millar: "Here are some highlights from the 2065 networking commits that happened this development cycle: 1) XDP support for IXGBE (John Fastabend) and thunderx (Sunil Kowuri) 2) Add a generic XDP driver, so that anyone can test XDP even if they lack a networking device whose driver has explicit XDP support (me). 3) Sparc64 now has an eBPF JIT too (me) 4) Add a BPF program testing framework via BPF_PROG_TEST_RUN (Alexei Starovoitov) 5) Make netfitler network namespace teardown less expensive (Florian Westphal) 6) Add symmetric hashing support to nft_hash (Laura Garcia Liebana) 7) Implement NAPI and GRO in netvsc driver (Stephen Hemminger) 8) Support TC flower offload statistics in mlxsw (Arkadi Sharshevsky) 9) Multiqueue support in stmmac driver (Joao Pinto) 10) Remove TCP timewait recycling, it never really could possibly work well in the real world and timestamp randomization really zaps any hint of usability this feature had (Soheil Hassas Yeganeh) 11) Support level3 vs level4 ECMP route hashing in ipv4 (Nikolay Aleksandrov) 12) Add socket busy poll support to epoll (Sridhar Samudrala) 13) Netlink extended ACK support (Johannes Berg, Pablo Neira Ayuso, and several others) 14) IPSEC hw offload infrastructure (Steffen Klassert)" * git://git.kernel.org/pub/scm/linux/kernel/git/davem/net-next: (2065 commits) tipc: refactor function tipc_sk_recv_stream() tipc: refactor function tipc_sk_recvmsg() net: thunderx: Optimize page recycling for XDP net: thunderx: Support for XDP header adjustment net: thunderx: Add support for XDP_TX net: thunderx: Add support for XDP_DROP net: thunderx: Add basic XDP support net: thunderx: Cleanup receive buffer allocation net: thunderx: Optimize CQE_TX handling net: thunderx: Optimize RBDR descriptor handling net: thunderx: Support for page recycling ipx: call ipxitf_put() in ioctl error path net: sched: add helpers to handle extended actions qed*: Fix issues in the ptp filter config implementation. qede: Fix concurrency issue in PTP Tx path processing. stmmac: Add support for SIMATIC IOT2000 platform net: hns: fix ethtool_get_strings overflow in hns driver tcp: fix wraparound issue in tcp_lp bpf, arm64: fix jit branch offset related to ldimm64 bpf, arm64: implement jiting of BPF_XADD ...
Diffstat (limited to 'drivers/net/ethernet/netronome/nfp/nfpcore/nfp_mutex.c')
-rw-r--r--drivers/net/ethernet/netronome/nfp/nfpcore/nfp_mutex.c345
1 files changed, 345 insertions, 0 deletions
diff --git a/drivers/net/ethernet/netronome/nfp/nfpcore/nfp_mutex.c b/drivers/net/ethernet/netronome/nfp/nfpcore/nfp_mutex.c
new file mode 100644
index 000000000000..8a99c189efa8
--- /dev/null
+++ b/drivers/net/ethernet/netronome/nfp/nfpcore/nfp_mutex.c
@@ -0,0 +1,345 @@
+/*
+ * Copyright (C) 2015-2017 Netronome Systems, Inc.
+ *
+ * This software is dual licensed under the GNU General License Version 2,
+ * June 1991 as shown in the file COPYING in the top-level directory of this
+ * source tree or the BSD 2-Clause License provided below. You have the
+ * option to license this software under the complete terms of either license.
+ *
+ * The BSD 2-Clause License:
+ *
+ * Redistribution and use in source and binary forms, with or
+ * without modification, are permitted provided that the following
+ * conditions are met:
+ *
+ * 1. Redistributions of source code must retain the above
+ * copyright notice, this list of conditions and the following
+ * disclaimer.
+ *
+ * 2. Redistributions in binary form must reproduce the above
+ * copyright notice, this list of conditions and the following
+ * disclaimer in the documentation and/or other materials
+ * provided with the distribution.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
+ * EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
+ * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
+ * NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS
+ * BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN
+ * ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN
+ * CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
+ * SOFTWARE.
+ */
+
+#include <linux/delay.h>
+#include <linux/device.h>
+#include <linux/jiffies.h>
+#include <linux/types.h>
+#include <linux/slab.h>
+#include <linux/wait.h>
+
+#include "nfp_cpp.h"
+#include "nfp6000/nfp6000.h"
+
+struct nfp_cpp_mutex {
+ struct nfp_cpp *cpp;
+ int target;
+ u16 depth;
+ unsigned long long address;
+ u32 key;
+};
+
+static u32 nfp_mutex_locked(u16 interface)
+{
+ return (u32)interface << 16 | 0x000f;
+}
+
+static u32 nfp_mutex_unlocked(u16 interface)
+{
+ return (u32)interface << 16 | 0x0000;
+}
+
+static bool nfp_mutex_is_locked(u32 val)
+{
+ return (val & 0xffff) == 0x000f;
+}
+
+static bool nfp_mutex_is_unlocked(u32 val)
+{
+ return (val & 0xffff) == 0000;
+}
+
+/* If you need more than 65536 recursive locks, please rethink your code. */
+#define NFP_MUTEX_DEPTH_MAX 0xffff
+
+static int
+nfp_cpp_mutex_validate(u16 interface, int *target, unsigned long long address)
+{
+ /* Not permitted on invalid interfaces */
+ if (NFP_CPP_INTERFACE_TYPE_of(interface) ==
+ NFP_CPP_INTERFACE_TYPE_INVALID)
+ return -EINVAL;
+
+ /* Address must be 64-bit aligned */
+ if (address & 7)
+ return -EINVAL;
+
+ if (*target != NFP_CPP_TARGET_MU)
+ return -EINVAL;
+
+ return 0;
+}
+
+/**
+ * nfp_cpp_mutex_init() - Initialize a mutex location
+ * @cpp: NFP CPP handle
+ * @target: NFP CPP target ID (ie NFP_CPP_TARGET_CLS or NFP_CPP_TARGET_MU)
+ * @address: Offset into the address space of the NFP CPP target ID
+ * @key: Unique 32-bit value for this mutex
+ *
+ * The CPP target:address must point to a 64-bit aligned location, and
+ * will initialize 64 bits of data at the location.
+ *
+ * This creates the initial mutex state, as locked by this
+ * nfp_cpp_interface().
+ *
+ * This function should only be called when setting up
+ * the initial lock state upon boot-up of the system.
+ *
+ * Return: 0 on success, or -errno on failure
+ */
+int nfp_cpp_mutex_init(struct nfp_cpp *cpp,
+ int target, unsigned long long address, u32 key)
+{
+ const u32 muw = NFP_CPP_ID(target, 4, 0); /* atomic_write */
+ u16 interface = nfp_cpp_interface(cpp);
+ int err;
+
+ err = nfp_cpp_mutex_validate(interface, &target, address);
+ if (err)
+ return err;
+
+ err = nfp_cpp_writel(cpp, muw, address + 4, key);
+ if (err)
+ return err;
+
+ err = nfp_cpp_writel(cpp, muw, address, nfp_mutex_locked(interface));
+ if (err)
+ return err;
+
+ return 0;
+}
+
+/**
+ * nfp_cpp_mutex_alloc() - Create a mutex handle
+ * @cpp: NFP CPP handle
+ * @target: NFP CPP target ID (ie NFP_CPP_TARGET_CLS or NFP_CPP_TARGET_MU)
+ * @address: Offset into the address space of the NFP CPP target ID
+ * @key: 32-bit unique key (must match the key at this location)
+ *
+ * The CPP target:address must point to a 64-bit aligned location, and
+ * reserve 64 bits of data at the location for use by the handle.
+ *
+ * Only target/address pairs that point to entities that support the
+ * MU Atomic Engine's CmpAndSwap32 command are supported.
+ *
+ * Return: A non-NULL struct nfp_cpp_mutex * on success, NULL on failure.
+ */
+struct nfp_cpp_mutex *nfp_cpp_mutex_alloc(struct nfp_cpp *cpp, int target,
+ unsigned long long address, u32 key)
+{
+ const u32 mur = NFP_CPP_ID(target, 3, 0); /* atomic_read */
+ u16 interface = nfp_cpp_interface(cpp);
+ struct nfp_cpp_mutex *mutex;
+ int err;
+ u32 tmp;
+
+ err = nfp_cpp_mutex_validate(interface, &target, address);
+ if (err)
+ return NULL;
+
+ err = nfp_cpp_readl(cpp, mur, address + 4, &tmp);
+ if (err < 0)
+ return NULL;
+
+ if (tmp != key)
+ return NULL;
+
+ mutex = kzalloc(sizeof(*mutex), GFP_KERNEL);
+ if (!mutex)
+ return NULL;
+
+ mutex->cpp = cpp;
+ mutex->target = target;
+ mutex->address = address;
+ mutex->key = key;
+ mutex->depth = 0;
+
+ return mutex;
+}
+
+/**
+ * nfp_cpp_mutex_free() - Free a mutex handle - does not alter the lock state
+ * @mutex: NFP CPP Mutex handle
+ */
+void nfp_cpp_mutex_free(struct nfp_cpp_mutex *mutex)
+{
+ kfree(mutex);
+}
+
+/**
+ * nfp_cpp_mutex_lock() - Lock a mutex handle, using the NFP MU Atomic Engine
+ * @mutex: NFP CPP Mutex handle
+ *
+ * Return: 0 on success, or -errno on failure
+ */
+int nfp_cpp_mutex_lock(struct nfp_cpp_mutex *mutex)
+{
+ unsigned long warn_at = jiffies + 15 * HZ;
+ unsigned int timeout_ms = 1;
+ int err;
+
+ /* We can't use a waitqueue here, because the unlocker
+ * might be on a separate CPU.
+ *
+ * So just wait for now.
+ */
+ for (;;) {
+ err = nfp_cpp_mutex_trylock(mutex);
+ if (err != -EBUSY)
+ break;
+
+ err = msleep_interruptible(timeout_ms);
+ if (err != 0)
+ return -ERESTARTSYS;
+
+ if (time_is_before_eq_jiffies(warn_at)) {
+ warn_at = jiffies + 60 * HZ;
+ nfp_warn(mutex->cpp,
+ "Warning: waiting for NFP mutex [depth:%hd target:%d addr:%llx key:%08x]\n",
+ mutex->depth,
+ mutex->target, mutex->address, mutex->key);
+ }
+ }
+
+ return err;
+}
+
+/**
+ * nfp_cpp_mutex_unlock() - Unlock a mutex handle, using the MU Atomic Engine
+ * @mutex: NFP CPP Mutex handle
+ *
+ * Return: 0 on success, or -errno on failure
+ */
+int nfp_cpp_mutex_unlock(struct nfp_cpp_mutex *mutex)
+{
+ const u32 muw = NFP_CPP_ID(mutex->target, 4, 0); /* atomic_write */
+ const u32 mur = NFP_CPP_ID(mutex->target, 3, 0); /* atomic_read */
+ struct nfp_cpp *cpp = mutex->cpp;
+ u32 key, value;
+ u16 interface;
+ int err;
+
+ interface = nfp_cpp_interface(cpp);
+
+ if (mutex->depth > 1) {
+ mutex->depth--;
+ return 0;
+ }
+
+ err = nfp_cpp_readl(mutex->cpp, mur, mutex->address + 4, &key);
+ if (err < 0)
+ return err;
+
+ if (key != mutex->key)
+ return -EPERM;
+
+ err = nfp_cpp_readl(mutex->cpp, mur, mutex->address, &value);
+ if (err < 0)
+ return err;
+
+ if (value != nfp_mutex_locked(interface))
+ return -EACCES;
+
+ err = nfp_cpp_writel(cpp, muw, mutex->address,
+ nfp_mutex_unlocked(interface));
+ if (err < 0)
+ return err;
+
+ mutex->depth = 0;
+ return 0;
+}
+
+/**
+ * nfp_cpp_mutex_trylock() - Attempt to lock a mutex handle
+ * @mutex: NFP CPP Mutex handle
+ *
+ * Return: 0 if the lock succeeded, -errno on failure
+ */
+int nfp_cpp_mutex_trylock(struct nfp_cpp_mutex *mutex)
+{
+ const u32 muw = NFP_CPP_ID(mutex->target, 4, 0); /* atomic_write */
+ const u32 mus = NFP_CPP_ID(mutex->target, 5, 3); /* test_set_imm */
+ const u32 mur = NFP_CPP_ID(mutex->target, 3, 0); /* atomic_read */
+ struct nfp_cpp *cpp = mutex->cpp;
+ u32 key, value, tmp;
+ int err;
+
+ if (mutex->depth > 0) {
+ if (mutex->depth == NFP_MUTEX_DEPTH_MAX)
+ return -E2BIG;
+ mutex->depth++;
+ return 0;
+ }
+
+ /* Verify that the lock marker is not damaged */
+ err = nfp_cpp_readl(cpp, mur, mutex->address + 4, &key);
+ if (err < 0)
+ return err;
+
+ if (key != mutex->key)
+ return -EPERM;
+
+ /* Compare against the unlocked state, and if true,
+ * write the interface id into the top 16 bits, and
+ * mark as locked.
+ */
+ value = nfp_mutex_locked(nfp_cpp_interface(cpp));
+
+ /* We use test_set_imm here, as it implies a read
+ * of the current state, and sets the bits in the
+ * bytemask of the command to 1s. Since the mutex
+ * is guaranteed to be 64-bit aligned, the bytemask
+ * of this 32-bit command is ensured to be 8'b00001111,
+ * which implies that the lower 4 bits will be set to
+ * ones regardless of the initial state.
+ *
+ * Since this is a 'Readback' operation, with no Pull
+ * data, we can treat this as a normal Push (read)
+ * atomic, which returns the original value.
+ */
+ err = nfp_cpp_readl(cpp, mus, mutex->address, &tmp);
+ if (err < 0)
+ return err;
+
+ /* Was it unlocked? */
+ if (nfp_mutex_is_unlocked(tmp)) {
+ /* The read value can only be 0x....0000 in the unlocked state.
+ * If there was another contending for this lock, then
+ * the lock state would be 0x....000f
+ */
+
+ /* Write our owner ID into the lock
+ * While not strictly necessary, this helps with
+ * debug and bookkeeping.
+ */
+ err = nfp_cpp_writel(cpp, muw, mutex->address, value);
+ if (err < 0)
+ return err;
+
+ mutex->depth = 1;
+ return 0;
+ }
+
+ return nfp_mutex_is_locked(tmp) ? -EBUSY : -EINVAL;
+}