* Re: [PATCH] net/core: Fix seeking in /proc/net/dev
From: Eric Dumazet @ 2012-04-06 17:43 UTC (permalink / raw)
To: David Miller; +Cc: john, netdev, linux-kernel, mihai.maruseac
In-Reply-To: <20120406.131800.651812823796333479.davem@davemloft.net>
On Fri, 2012-04-06 at 13:18 -0400, David Miller wrote:
> Eric Dumazet already fixed this the other day.
> --
John, take a look at
http://git.kernel.org/?p=linux/kernel/git/davem/net.git;a=commit;h=2def16ae6b0c77571200f18ba4be049b03d75579
Thanks
^ permalink raw reply
* Re: [PATCH net-next V2] tcp: Fix bug when gap in rcv sequence is filled
From: chetan loke @ 2012-04-06 18:06 UTC (permalink / raw)
To: Vijay Subramanian; +Cc: netdev, davem, ncardwell, ilpo.jarvinen
In-Reply-To: <1333733810-2381-1-git-send-email-subramanian.vijay@gmail.com>
On Fri, Apr 6, 2012 at 1:36 PM, Vijay Subramanian
<subramanian.vijay@gmail.com> wrote:
> + int requeued = 0; /*1 if an skb is requeued to receive_queue*/
Vijay - minor change: missing leading/trailing space in the comment.
checkpatch.pl ?
Chetan
^ permalink raw reply
* Re: ipv6: tunnel: hang when destroying ipv6 tunnel
From: Jim Garlick @ 2012-04-06 18:09 UTC (permalink / raw)
To: Tetsuo Handa
Cc: levinsasha928@gmail.com, ericvh@gmail.com, oleg@redhat.com,
eric.dumazet@gmail.com, davem@davemloft.net, kuznet@ms2.inr.ac.ru,
jmorris@namei.org, yoshfuji@linux-ipv6.org, kaber@trash.net,
netdev@vger.kernel.org, linux-kernel@vger.kernel.org,
davej@redhat.com
In-Reply-To: <201204062044.EJE13062.OLMQtSVFHOFOJF@I-love.SAKURA.ne.jp>
Hi Tetsuo,
I am sorry if my patch is causing you grief!
On Fri, Apr 06, 2012 at 04:44:37AM -0700, Tetsuo Handa wrote:
> Tetsuo Handa wrote:
> > Most suspicious change is net/9p/client.c because it is changing handling of
> > ERESTARTSYS case.
> >
> > --- linux-3.3.1/net/9p/client.c
> > +++ linux-next/net/9p/client.c
> > @@ -740,10 +740,18 @@
> > c->status = Disconnected;
> > goto reterr;
> > }
> > +again:
> > /* Wait for the response */
> > err = wait_event_interruptible(*req->wq,
> > req->status >= REQ_STATUS_RCVD);
> >
> > + if ((err == -ERESTARTSYS) && (c->status == Connected)
> > + && (type == P9_TFLUSH)) {
> > + sigpending = 1;
> > + clear_thread_flag(TIF_SIGPENDING);
> > + goto again;
> > + }
> > +
>
> I think this loop is bad with regard to response to SIGKILL.
> If wait_event_interruptible() was interrupted by SIGKILL, it will
> spin until req->status >= REQ_STATUS_RCVD becomes true.
> Rather,
>
> if ((c->status == Connected) && (type == P9_TFLUSH))
> err = wait_event_killable(*req->wq,
> req->status >= REQ_STATUS_RCVD);
> else
> err = wait_event_interruptible(*req->wq,
> req->status >= REQ_STATUS_RCVD);
>
> would be safer.
Does that work? What prevents p9_client_rpc() from recursing via
p9_client_flush() on receipt of SIGKILL?
> > error:
> > /*
> > * Fid is not valid even after a failed clunk
> > + * If interrupted, retry once then give up and
> > + * leak fid until umount.
> > */
> > - p9_fid_destroy(fid);
> > + if (err == -ERESTARTSYS) {
> > + if (retries++ == 0)
> > + goto again;
>
> I think it is possible that the process is interrupted again upon retrying.
> I suspect the handling of err == -ERESTARTSYS case when retries != 0.
> It is returning without calling p9_fid_destroy(), which will be
> unexpected behaviour for the various callers.
Yes but in the unlikely event that this happens, the effect is a small
memory leak for the duration of the mount. On the other hand if the
fid is destroyed without successfully informing the server, then
subsequent operations that involve new file references will fail
when that fid number is reused, and the mount becomes unusable.
> > + } else
> > + p9_fid_destroy(fid);
> > return err;
> > }
> > EXPORT_SYMBOL(p9_client_clunk);
Regards,
Jim
^ permalink raw reply
* Re: [RFC] net/hsr: Add support for IEC 62439-3 High-availability Seamless Redundancy
From: Stephen Hemminger @ 2012-04-06 18:19 UTC (permalink / raw)
To: Ben Hutchings
Cc: Arvid Brodin, David Miller, netdev, balferreira, arvid.brodin
In-Reply-To: <1333731991.3282.17.camel@deadeye>
On Fri, 6 Apr 2012 18:06:31 +0100
Ben Hutchings <bhutchings@solarflare.com> wrote:
> On Fri, 2012-04-06 at 17:51 +0200, Arvid Brodin wrote:
> > David Miller wrote:
> > > From: Stephen Hemminger <shemminger@vyatta.com>
> > > Date: Wed, 4 Apr 2012 16:55:59 -0700
> > >
> > >> That isn't so bad, doing a memcpy versus a structure copy.
> > >
> > > GCC is going to inline the memcpy and thus we'll still do the
> > > unaligned accesses. This change therefore won't fix the problem.
> >
> > Well, it does work for me, with gcc-4.2.2-compiled linux-2.6.37 running
> > on an AVR32 board.
> >
> > Just out of curiosity, what's the mechanism behind this inline
> > assignment that turns the memcpy into an unaligned access? If gcc is
> > "smart" enough to detect a bunch of char * accesses and turn them
> > into unaligned 32-bit accesses, isn't that a bug in gcc?
>
> If I remember correctly, casting a char* pointer to foo* where the
> original pointer isn't properly aligned for type foo results in
> undefined behaviour. And that is what icmp_hdr() is doing, so there is
> no requirement that the compiler does anything reasonable with the
> result. Removing that cast (using skb_transport_header() instead of
> icmp_hdr()) should avoid that.
>
> (We do generally assume, however, that if the processor can handle
> unaligned accesses in a useful way then the compiler will be reasonable
> and not break them.)
>
> Ben.
>
> > Or will this only happen on archs which __HAVE_ARCH_MEMCPY? (But looking
> > at a couple of arch/xxx/lib/string.c, these too seem to take alignment
> > into account.)
> >
>
Since icmp_hdr is 64 bits you might be able to use get_unaligned64
in some way.
^ permalink raw reply
* Re: [PATCH] net/core: Fix seeking in /proc/net/dev
From: John Keeping @ 2012-04-06 18:19 UTC (permalink / raw)
To: Eric Dumazet; +Cc: David Miller, netdev, linux-kernel, mihai.maruseac
In-Reply-To: <1333734192.3007.5.camel@edumazet-glaptop>
On 06.04.2012 17:43, Eric Dumazet wrote:
> On Fri, 2012-04-06 at 13:18 -0400, David Miller wrote:
>> Eric Dumazet already fixed this the other day.
>> --
>
>
> http://git.kernel.org/?p=linux/kernel/git/davem/net.git;a=commit;h=2def16ae6b0c77571200f18ba4be049b03d75579
This does indeed fix the same bug. That will teach me not to check the
appropriate maintainer's tree before sending a patch!
Sorry for the noise,
John
^ permalink raw reply
* Re: [PATCH net-next V2] tcp: Fix bug when gap in rcv sequence is filled
From: Vijay Subramanian @ 2012-04-06 18:27 UTC (permalink / raw)
To: chetan loke; +Cc: netdev, davem, ncardwell, ilpo.jarvinen
In-Reply-To: <CAAsGZS4w=2_e9O=cRK6r+gxirohhSPHpgkNpWw_ZvC-+Q-pHkA@mail.gmail.com>
>> + int requeued = 0; /*1 if an skb is requeued to receive_queue*/
>
> Vijay - minor change: missing leading/trailing space in the comment.
> checkpatch.pl ?
Thanks for the reviews Chetan. checkpatch.pl reported no errors and no
warnings however.
I will wait for additional feedback from TCP folks and send version V3
if needed.
Thanks,
Vijay
^ permalink raw reply
* Re: Expose ltr/obff interface by sysfs
From: Konrad Rzeszutek Wilk @ 2012-04-06 18:39 UTC (permalink / raw)
To: Hao, Xudong
Cc: e1000-devel@lists.sourceforge.net, linux-pci@vger.kernel.org,
Jesse Barnes, netdev@vger.kernel.org
In-Reply-To: <403610A45A2B5242BD291EDAE8B37D300FD0A434@SHSMSX102.ccr.corp.intel.com>
On Fri, Apr 06, 2012 at 02:43:59AM +0000, Hao, Xudong wrote:
> Hi,
>
> I'm working on virtualization Xen/KVM. I saw there are ltr/obff enabling/disabling function in pci.c, but no called till now. I want to know if anybody(driver developer) are working for using it? Can driver change the LTR latency value dynamically?
>
> /*
> LTR(Latency tolerance reporting) allows devices to send messages to the root complex indicating their latency tolerance for snooped & unsnooped memory transactions.
> OBFF (optimized buffer flush/fill), where supported, can help improve energy efficiency by giving devices information about when interrupts and other activity will have a reduced power impact.
> */
>
> One way to control ltr/obff is used by driver, however, I'm considering that in virtualization, how guest OS driver control them. I have an idea that expose an inode interface by sysfs, like "reset" inode implemented in pci-sysfs.c, so that system user/administrator can enable/disable ltr/obff or set latency value on userspace, but not limited on driver. Comments?
So right now the driver inside the guest can probably see it, but can't change them.
(As those requests end up being filtered).
But there is nothing wrong with your changing those values from within the host.
But a better question is - why should this be done - especially from the guest which
has a limited view of the machine? The machine might be running a lot of other
requests so the OBFF inside the guest could be invalid.
>
> < pls CC me when reply this mail, thanks >
>
> Best Regards,
> Xudong Hao
>
> --
> To unsubscribe from this list: send the line "unsubscribe linux-pci" in
> the body of a message to majordomo@vger.kernel.org
> More majordomo info at http://vger.kernel.org/majordomo-info.html
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^ permalink raw reply
* [REGRESSION][PATCH v1] bpf jit: Let the arm jit handle negative memory references
From: Jan Seiffert @ 2012-04-06 18:57 UTC (permalink / raw)
To: netdev
Cc: linux-kernel, Eric Dumazet, David S. Miller, Mircea Gherzan,
Russell King
In-Reply-To: <4F75CA89.4010709@googlemail.com>
The arm jit has the same problem as the other two jits.
It only tests for negative absolute memory references, and if it sees
one bails out to let the interpreter handle the filter program.
But this fails if the X register contains a negative memory reference
and is used for an indirect load.
This is only caught at runtime, where the filter will always drop
the packet.
Filter which work fine with the interpreter do not work with the jit.
So this patch tries to fix it for the arm jit.
First we add the prototype of bpf_internal_load_pointer_neg_helper to
filter.h, since the arm jit has no assembler component, instead it has
to be used from C.
Then the helper functions are prepared to either handle known positive
offsets, known negative offsets, or any offset and test at runtime.
Finally the compiler is modified to emit calls to the right function,
depending if either the offset is known, or not.
This fixes the case of a negative X register and allows to lift
the restriction that bpf programs with negative offsets can't
be jited.
Signed-off-by: Jan Seiffert <kaffeemonster@googlemail.com>
---
The arm jit structure is a little bit different then the other jits, esp.
it does not use assembler load helper. So i had to put the prototype for
bpf_internal_load_pointer_neg_helper somewhere.
This is a v1 to keep the ball rolling.
Testing would also be cool, -ENOHARDWARE.
arch/arm/net/bpf_jit_32.c | 149 ++++++++++++++++++++++++++++++++-------------
include/linux/filter.h | 6 ++
net/core/filter.c | 4 +
3 files changed, 117 insertions(+), 42 deletions(-)
diff --git a/arch/arm/net/bpf_jit_32.c b/arch/arm/net/bpf_jit_32.c
index 62135849..19d60af 100644
--- a/arch/arm/net/bpf_jit_32.c
+++ b/arch/arm/net/bpf_jit_32.c
@@ -18,6 +18,7 @@
#include <linux/slab.h>
#include <asm/cacheflush.h>
#include <asm/hwcap.h>
+#include <asm/unaligned.h>
#include "bpf_jit_32.h"
@@ -71,7 +72,7 @@ struct jit_ctx {
int bpf_jit_enable __read_mostly;
-static u64 jit_get_skb_b(struct sk_buff *skb, unsigned offset)
+static u64 jit_get_skb_b_pos(struct sk_buff *skb, unsigned offset)
{
u8 ret;
int err;
@@ -81,7 +82,7 @@ static u64 jit_get_skb_b(struct sk_buff *skb, unsigned offset)
return (u64)err << 32 | ret;
}
-static u64 jit_get_skb_h(struct sk_buff *skb, unsigned offset)
+static u64 jit_get_skb_h_pos(struct sk_buff *skb, unsigned offset)
{
u16 ret;
int err;
@@ -91,7 +92,7 @@ static u64 jit_get_skb_h(struct sk_buff *skb, unsigned offset)
return (u64)err << 32 | ntohs(ret);
}
-static u64 jit_get_skb_w(struct sk_buff *skb, unsigned offset)
+static u64 jit_get_skb_w_pos(struct sk_buff *skb, unsigned offset)
{
u32 ret;
int err;
@@ -101,6 +102,60 @@ static u64 jit_get_skb_w(struct sk_buff *skb, unsigned offset)
return (u64)err << 32 | ntohl(ret);
}
+static u64 jit_get_skb_b_neg(struct sk_buff *skb, unsigned offset)
+{
+ u8 *ptr;
+
+ ptr = bpf_internal_load_pointer_neg_helper(skb, offset, 1);
+ if (!ptr)
+ return (u64)1 << 32;
+ return *ptr;
+}
+
+static u64 jit_get_skb_h_neg(struct sk_buff *skb, unsigned offset)
+{
+ u16 *ptr;
+
+ ptr = bpf_internal_load_pointer_neg_helper(skb, offset, 2);
+ if (!ptr)
+ return (u64)1 << 32;
+ return get_unaligned_be16(ptr);
+}
+
+static u64 jit_get_skb_w_neg(struct sk_buff *skb, unsigned offset)
+{
+ u32 *ptr;
+
+ ptr = bpf_internal_load_pointer_neg_helper(skb, offset, 4);
+ if (!ptr)
+ return (u64)1 << 32;
+ return get_unaligned_be32(ptr);
+}
+
+static u64 jit_get_skb_b_any(struct sk_buff *skb, unsigned offset)
+{
+ if ((int)offset >= 0)
+ return jit_get_skb_b_pos(skb, offset);
+ else
+ return jit_get_skb_b_neg(skb, offset);
+}
+
+static u64 jit_get_skb_h_any(struct sk_buff *skb, unsigned offset)
+{
+ if ((int)offset >= 0)
+ return jit_get_skb_h_pos(skb, offset);
+ else
+ return jit_get_skb_h_neg(skb, offset);
+}
+
+static u64 jit_get_skb_w_any(struct sk_buff *skb, unsigned offset)
+{
+ if ((int)offset >= 0)
+ return jit_get_skb_w_pos(skb, offset);
+ else
+ return jit_get_skb_w_neg(skb, offset);
+}
+
/*
* Wrapper that handles both OABI and EABI and assures Thumb2 interworking
* (where the assembly routines like __aeabi_uidiv could cause problems).
@@ -458,7 +513,10 @@ static inline void update_on_xread(struct jit_ctx *ctx)
static int build_body(struct jit_ctx *ctx)
{
- void *load_func[] = {jit_get_skb_b, jit_get_skb_h, jit_get_skb_w};
+ void *load_func_any[] = {jit_get_skb_b_any, jit_get_skb_h_any, jit_get_skb_w_any};
+ void *load_func_pos[] = {jit_get_skb_b_pos, jit_get_skb_h_pos, jit_get_skb_w_pos};
+ void *load_func_neg[] = {jit_get_skb_b_neg, jit_get_skb_h_neg, jit_get_skb_w_neg};
+ void **load_func;
const struct sk_filter *prog = ctx->skf;
const struct sock_filter *inst;
unsigned i, load_order, off, condt;
@@ -498,36 +556,38 @@ static int build_body(struct jit_ctx *ctx)
case BPF_S_LD_B_ABS:
load_order = 0;
load:
- /* the interpreter will deal with the negative K */
- if ((int)k < 0)
- return -ENOTSUPP;
emit_mov_i(r_off, k, ctx);
-load_common:
- ctx->seen |= SEEN_DATA | SEEN_CALL;
-
- if (load_order > 0) {
- emit(ARM_SUB_I(r_scratch, r_skb_hl,
- 1 << load_order), ctx);
- emit(ARM_CMP_R(r_scratch, r_off), ctx);
- condt = ARM_COND_HS;
- } else {
- emit(ARM_CMP_R(r_skb_hl, r_off), ctx);
- condt = ARM_COND_HI;
- }
- _emit(condt, ARM_ADD_R(r_scratch, r_off, r_skb_data),
- ctx);
-
- if (load_order == 0)
- _emit(condt, ARM_LDRB_I(r_A, r_scratch, 0),
+ /* deal with negative K */
+ if (k >= 0) {
+ load_func = load_func_pos;
+ if (load_order > 0) {
+ emit(ARM_SUB_I(r_scratch, r_skb_hl,
+ 1 << load_order), ctx);
+ emit(ARM_CMP_R(r_scratch, r_off), ctx);
+ condt = ARM_COND_HS;
+ } else {
+ emit(ARM_CMP_R(r_skb_hl, r_off), ctx);
+ condt = ARM_COND_HI;
+ }
+
+ _emit(condt, ARM_ADD_R(r_scratch, r_off, r_skb_data),
ctx);
- else if (load_order == 1)
- emit_load_be16(condt, r_A, r_scratch, ctx);
- else if (load_order == 2)
- emit_load_be32(condt, r_A, r_scratch, ctx);
- _emit(condt, ARM_B(b_imm(i + 1, ctx)), ctx);
+ if (load_order == 0)
+ _emit(condt, ARM_LDRB_I(r_A, r_scratch, 0),
+ ctx);
+ else if (load_order == 1)
+ emit_load_be16(condt, r_A, r_scratch, ctx);
+ else if (load_order == 2)
+ emit_load_be32(condt, r_A, r_scratch, ctx);
+ _emit(condt, ARM_B(b_imm(i + 1, ctx)), ctx);
+ } else {
+ load_func = load_func_neg;
+ }
+load_common:
+ ctx->seen |= SEEN_DATA | SEEN_CALL;
/* the slowpath */
emit_mov_i(ARM_R3, (u32)load_func[load_order], ctx);
emit(ARM_MOV_R(ARM_R0, r_skb), ctx);
@@ -547,7 +607,9 @@ load_common:
case BPF_S_LD_B_IND:
load_order = 0;
load_ind:
+ load_func = load_func_any;
OP_IMM3(ARM_ADD, r_off, r_X, k, ctx);
+ load_func = load_func_any;
goto load_common;
case BPF_S_LDX_IMM:
ctx->seen |= SEEN_X;
@@ -565,25 +627,28 @@ load_ind:
case BPF_S_LDX_B_MSH:
/* x = ((*(frame + k)) & 0xf) << 2; */
ctx->seen |= SEEN_X | SEEN_DATA | SEEN_CALL;
- /* the interpreter should deal with the negative K */
- if (k < 0)
- return -1;
/* offset in r1: we might have to take the slow path */
emit_mov_i(r_off, k, ctx);
- emit(ARM_CMP_R(r_skb_hl, r_off), ctx);
+ /* deal with negative K */
+ if (k >= 0) {
+ load_func = load_func_pos;
+ emit(ARM_CMP_R(r_skb_hl, r_off), ctx);
- /* load in r0: common with the slowpath */
- _emit(ARM_COND_HI, ARM_LDRB_R(ARM_R0, r_skb_data,
- ARM_R1), ctx);
- /*
- * emit_mov_i() might generate one or two instructions,
- * the same holds for emit_blx_r()
- */
- _emit(ARM_COND_HI, ARM_B(b_imm(i + 1, ctx) - 2), ctx);
+ /* load in r0: common with the slowpath */
+ _emit(ARM_COND_HI, ARM_LDRB_R(ARM_R0, r_skb_data,
+ ARM_R1), ctx);
+ /*
+ * emit_mov_i() might generate one or two instructions,
+ * the same holds for emit_blx_r()
+ */
+ _emit(ARM_COND_HI, ARM_B(b_imm(i + 1, ctx) - 2), ctx);
+ } else {
+ load_func = load_func_neg;
+ }
emit(ARM_MOV_R(ARM_R0, r_skb), ctx);
/* r_off is r1 */
- emit_mov_i(ARM_R3, (u32)jit_get_skb_b, ctx);
+ emit_mov_i(ARM_R3, (u32)load_func[0], ctx);
emit_blx_r(ARM_R3, ctx);
/* check the return value of skb_copy_bits */
emit(ARM_CMP_I(ARM_R1, 0), ctx);
diff --git a/include/linux/filter.h b/include/linux/filter.h
index 8eeb205..78cd56d 100644
--- a/include/linux/filter.h
+++ b/include/linux/filter.h
@@ -161,6 +161,12 @@ extern int sk_chk_filter(struct sock_filter *filter, unsigned int flen);
extern void bpf_jit_compile(struct sk_filter *fp);
extern void bpf_jit_free(struct sk_filter *fp);
#define SK_RUN_FILTER(FILTER, SKB) (*FILTER->bpf_func)(SKB, FILTER->insns)
+/*
+ * Only Exported for the bpf jit load helper.
+ * Do not call from anywhere else!
+ */
+extern void *bpf_internal_load_pointer_neg_helper(const struct sk_buff *skb,
+ int k, unsigned int size);
#else
static inline void bpf_jit_compile(struct sk_filter *fp)
{
diff --git a/net/core/filter.c b/net/core/filter.c
index 6f755cc..9cbaecb 100644
--- a/net/core/filter.c
+++ b/net/core/filter.c
@@ -42,6 +42,10 @@
/* No hurry in this branch
*
* Exported for the bpf jit load helper.
+ *
+ * CAUTION ! :
+ * If its prototype is ever changed, check arch/{*}/net/{*}.S files,
+ * since it is called from BPF assembly code.
*/
void *bpf_internal_load_pointer_neg_helper(const struct sk_buff *skb, int k, unsigned int size)
{
^ permalink raw reply related
* Re: [PATCH v17 01/15] Add PR_{GET,SET}_NO_NEW_PRIVS to prevent execve from granting privs
From: Andrew Morton @ 2012-04-06 19:49 UTC (permalink / raw)
To: Will Drewry
Cc: linux-kernel, linux-security-module, linux-arch, linux-doc,
kernel-hardening, netdev, x86, arnd, davem, hpa, mingo, oleg,
peterz, rdunlap, mcgrathr, tglx, luto, eparis, serge.hallyn, djm,
scarybeasts, indan, pmoore, corbet, eric.dumazet, markus, coreyb,
keescook, jmorris, Andy Lutomirski
In-Reply-To: <1333051320-30872-2-git-send-email-wad@chromium.org>
On Thu, 29 Mar 2012 15:01:46 -0500
Will Drewry <wad@chromium.org> wrote:
> From: Andy Lutomirski <luto@amacapital.net>
>
> With this set, a lot of dangerous operations (chroot, unshare, etc)
> become a lot less dangerous because there is no possibility of
> subverting privileged binaries.
>
> This patch completely breaks apparmor. Someone who understands (and
> uses) apparmor should fix it or at least give me a hint.
So [patch 2/15] fixes all this up?
I guess we should join the two patches into one, to avoid a silly
breakage window. That means that John loses a brownie point, but we
can mention him in the changelog, include his signed-off-by:
> Signed-off-by: Andy Lutomirski <luto@amacapital.net>
Several of these patches are missing your signed-off-by:. They should
all have your SOB, because you sent them.
Documentation/SubmittingPatches explains this.
I'm trying to find a way to merge all this code without reviewing it ;)
Alas, this is against my rules. Given the length of time for which
this patchset has been floating around, I'm a little surprised by the
lack of acked-by's and reviewed-by's. Have you been gathering them all
up? Are the networking guys all happy about this patchset?
^ permalink raw reply
* Re: [PATCH v17 01/15] Add PR_{GET,SET}_NO_NEW_PRIVS to prevent execve from granting privs
From: Andy Lutomirski @ 2012-04-06 19:55 UTC (permalink / raw)
To: Andrew Morton
Cc: Will Drewry, linux-kernel, linux-security-module, linux-arch,
linux-doc, kernel-hardening, netdev, x86, arnd, davem, hpa, mingo,
oleg, peterz, rdunlap, mcgrathr, tglx, luto, eparis, serge.hallyn,
djm, scarybeasts, indan, pmoore, corbet, eric.dumazet, markus,
coreyb, keescook, jmorris
In-Reply-To: <20120406124921.5754e941.akpm@linux-foundation.org>
On Fri, Apr 6, 2012 at 12:49 PM, Andrew Morton
<akpm@linux-foundation.org> wrote:
> On Thu, 29 Mar 2012 15:01:46 -0500
> Will Drewry <wad@chromium.org> wrote:
>
>> From: Andy Lutomirski <luto@amacapital.net>
>>
>> With this set, a lot of dangerous operations (chroot, unshare, etc)
>> become a lot less dangerous because there is no possibility of
>> subverting privileged binaries.
>>
>> This patch completely breaks apparmor. Someone who understands (and
>> uses) apparmor should fix it or at least give me a hint.
>
> So [patch 2/15] fixes all this up?
>
> I guess we should join the two patches into one, to avoid a silly
> breakage window. That means that John loses a brownie point, but we
> can mention him in the changelog, include his signed-off-by:
Or just fix the commit message. It no longer completely breaks
AppArmor. It just causes execve to fail when PR_SET_NO_NEW_PRIVS is
set and AppArmor is in use.
--Andy
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^ permalink raw reply
* Re: [PATCH v17 01/15] Add PR_{GET,SET}_NO_NEW_PRIVS to prevent execve from granting privs
From: Andrew Morton @ 2012-04-06 19:55 UTC (permalink / raw)
To: Will Drewry
Cc: linux-kernel-u79uwXL29TY76Z2rM5mHXA,
linux-security-module-u79uwXL29TY76Z2rM5mHXA,
linux-arch-u79uwXL29TY76Z2rM5mHXA,
linux-doc-u79uwXL29TY76Z2rM5mHXA,
kernel-hardening-ZwoEplunGu1jrUoiu81ncdBPR1lH4CV8,
netdev-u79uwXL29TY76Z2rM5mHXA, x86-DgEjT+Ai2ygdnm+yROfE0A,
arnd-r2nGTMty4D4, davem-fT/PcQaiUtIeIZ0/mPfg9Q,
hpa-YMNOUZJC4hwAvxtiuMwx3w, mingo-H+wXaHxf7aLQT0dZR+AlfA,
oleg-H+wXaHxf7aLQT0dZR+AlfA, peterz-wEGCiKHe2LqWVfeAwA7xHQ,
rdunlap-/UHa2rfvQTnk1uMJSBkQmQ, mcgrathr-F7+t8E8rja9g9hUCZPvPmw,
tglx-hfZtesqFncYOwBW4kG4KsQ, luto-3s7WtUTddSA,
eparis-H+wXaHxf7aLQT0dZR+AlfA,
serge.hallyn-Z7WLFzj8eWMS+FvcfC7Uqw, djm-ilwOsaqNJrtAfugRpC6u6w,
scarybeasts-Re5JQEeQqe8AvxtiuMwx3w, indan-1J6HnF7K7zE,
pmoore-H+wXaHxf7aLQT0dZR+AlfA, corbet-T1hC0tSOHrs,
eric.dumazet-Re5JQEeQqe8AvxtiuMwx3w,
markus-F7+t8E8rja9g9hUCZPvPmw,
coreyb-23VcF4HTsmIX0ybBhKVfKdBPR1lH4CV8,
keescook-F7+t8E8rja9g9hUCZPvPmw, jmorris-gx6/JNMH7DfYtjvyW6yDsg,
Andy Lutomirski, linux-man-u79uwXL29TY76Z2rM5mHXA
In-Reply-To: <1333051320-30872-2-git-send-email-wad-F7+t8E8rja9g9hUCZPvPmw@public.gmane.org>
On Thu, 29 Mar 2012 15:01:46 -0500
Will Drewry <wad-F7+t8E8rja9g9hUCZPvPmw@public.gmane.org> wrote:
> From: Andy Lutomirski <luto-kltTT9wpgjJwATOyAt5JVQ@public.gmane.org>
>
> With this set, a lot of dangerous operations (chroot, unshare, etc)
> become a lot less dangerous because there is no possibility of
> subverting privileged binaries.
The changelog doesn't explain the semantics of the new syscall.
There's a comment way-down-there which I guess suffices, if you hunt
for it.
And the changelog doesn't explain why this is being added. Presumably
seccomp_filter wants/needs this feature but whowhatwherewhenwhy? Spell
it all out, please.
The new syscall mode will be documented in the prctl manpage. Please
cc linux-man-u79uwXL29TY76Z2rM5mHXA@public.gmane.org and work with Michael on getting this
done?
>
> ...
>
--
To unsubscribe from this list: send the line "unsubscribe linux-man" in
the body of a message to majordomo-u79uwXL29TY76Z2rM5mHXA@public.gmane.org
More majordomo info at http://vger.kernel.org/majordomo-info.html
^ permalink raw reply
* Re: [PATCH v17 01/15] Add PR_{GET,SET}_NO_NEW_PRIVS to prevent execve from granting privs
From: Andrew Lutomirski @ 2012-04-06 20:01 UTC (permalink / raw)
To: Andrew Morton
Cc: Will Drewry, linux-kernel, linux-security-module, linux-arch,
linux-doc, kernel-hardening, netdev, x86, arnd, davem, hpa, mingo,
oleg, peterz, rdunlap, mcgrathr, tglx, eparis, serge.hallyn, djm,
scarybeasts, indan, pmoore, corbet, eric.dumazet, markus, coreyb,
keescook, jmorris, Andy Lutomirski, linux-man
In-Reply-To: <20120406125517.77133b4e.akpm@linux-foundation.org>
On Fri, Apr 6, 2012 at 12:55 PM, Andrew Morton
<akpm@linux-foundation.org> wrote:
> On Thu, 29 Mar 2012 15:01:46 -0500
> Will Drewry <wad@chromium.org> wrote:
>
>> From: Andy Lutomirski <luto@amacapital.net>
>>
>> With this set, a lot of dangerous operations (chroot, unshare, etc)
>> become a lot less dangerous because there is no possibility of
>> subverting privileged binaries.
>
> The changelog doesn't explain the semantics of the new syscall.
> There's a comment way-down-there which I guess suffices, if you hunt
> for it.
>
> And the changelog doesn't explain why this is being added. Presumably
> seccomp_filter wants/needs this feature but whowhatwherewhenwhy? Spell
> it all out, please.
>
> The new syscall mode will be documented in the prctl manpage. Please
> cc linux-man@vger.kernel.org and work with Michael on getting this
> done?
This has been bugging me for awhile. Is there any interest in moving
the manpages into the kernel source tree? Then there could be a
general requirement that new APIs get documented when they're written.
(There are plenty of barely- or incompletely-documented syscalls.
futex and relatives come to mind.)
--Andy
^ permalink raw reply
* Re: [PATCH v17 07/15] asm/syscall.h: add syscall_get_arch
From: Andrew Morton @ 2012-04-06 20:05 UTC (permalink / raw)
To: Will Drewry
Cc: linux-kernel, linux-security-module, linux-arch, linux-doc,
kernel-hardening, netdev, x86, arnd, davem, hpa, mingo, oleg,
peterz, rdunlap, mcgrathr, tglx, luto, eparis, serge.hallyn, djm,
scarybeasts, indan, pmoore, corbet, eric.dumazet, markus, coreyb,
keescook, jmorris
In-Reply-To: <1333051320-30872-8-git-send-email-wad@chromium.org>
On Thu, 29 Mar 2012 15:01:52 -0500
Will Drewry <wad@chromium.org> wrote:
> Adds a stub for a function that will return the AUDIT_ARCH_*
> value appropriate to the supplied task based on the system
> call convention.
>
> For audit's use, the value can generally be hard-coded at the
> audit-site. However, for other functionality not inlined into
> syscall entry/exit, this makes that information available.
> seccomp_filter is the first planned consumer and, as such,
> the comment indicates a tie to HAVE_ARCH_SECCOMP_FILTER. That
Should be "CONFIG_HAVE_ARCH_SECCOMP_FILTER", I hope.
> is probably an unneeded detail.
>
> ...
>
> --- a/include/asm-generic/syscall.h
> +++ b/include/asm-generic/syscall.h
> @@ -142,4 +142,18 @@ void syscall_set_arguments(struct task_struct *task, struct pt_regs *regs,
> unsigned int i, unsigned int n,
> const unsigned long *args);
>
> +/**
> + * syscall_get_arch - return the AUDIT_ARCH for the current system call
> + * @task: task of interest, must be in system call entry tracing
> + * @regs: task_pt_regs() of @task
> + *
> + * Returns the AUDIT_ARCH_* based on the system call convention in use.
> + *
> + * It's only valid to call this when @task is stopped on entry to a system
> + * call, due to %TIF_SYSCALL_TRACE, %TIF_SYSCALL_AUDIT, or %TIF_SECCOMP.
> + *
> + * Note, at present this function is only required with
> + * CONFIG_HAVE_ARCH_SECCOMP_FILTER.
> + */
> +int syscall_get_arch(struct task_struct *task, struct pt_regs *regs);
> #endif /* _ASM_SYSCALL_H */
So architectures which permit CONFIG_HAVE_ARCH_SECCOMP_FILTER must
provide an implementation of this.
^ permalink raw reply
* Is this intended design, or a bug? Missing event for gateway being deleted
From: Stian Skjelstad @ 2012-04-06 20:04 UTC (permalink / raw)
To: netdev
I'm sorry if this has been discussed before, but my google searches didn't
give me any good hints so:
I'm using rtnetlink for a project and I noticed a non-consistent behavior.
When I tear down (the last) ip address, the default gateway is removed,
but it is not announced on the netlink socket. This can also be verified
using "ip monitor". This is tested with linux kernel version 3.2.6 on ARM.
# ip monitor &
# ip addr add 10.0.0.2/8 dev eth0
2: eth0 inet 10.0.0.2/8 scope global eth0
local 10.0.0.2 dev eth0 table local proto kernel scope host src 10.0.0.2
10.0.0.0/8 dev eth0 proto kernel scope link src 10.0.0.2
broadcast 10.0.0.0 dev eth0 table local proto kernel scope link src
10.0.0.2
broadcast 10.255.255.255 dev eth0 table local proto kernel scope link
src 10.0.0.2
# ip route add via 10.0.1.22
default via 10.0.1.2 dev eth0
# ip addr del 10.0.0.2/8 dev eth0
Deleted 2: eth0 inet 10.0.0.2/8 scope global eth0
Deleted 10.0.0.0/8 dev eth0 proto kernel scope link src 10.0.0.2
Deleted broadcast 10.255.255.255 dev eth0 table local proto kernel
scope link src 10.0.0.2
Deleted broadcast 10.0.0.0 dev eth0 table local proto kernel scope link
src 10.0.0.2
Deleted local 10.0.0.2 dev eth0 table local proto kernel scope host
src 10.0.0.2
(No Deleted default via line here)
Stian Skjelstad
^ permalink raw reply
* Re: [PATCH v17 08/15] seccomp: add system call filtering using BPF
From: Andrew Morton @ 2012-04-06 20:23 UTC (permalink / raw)
To: Will Drewry
Cc: linux-kernel, linux-security-module, linux-arch, linux-doc,
kernel-hardening, netdev, x86, arnd, davem, hpa, mingo, oleg,
peterz, rdunlap, mcgrathr, tglx, luto, eparis, serge.hallyn, djm,
scarybeasts, indan, pmoore, corbet, eric.dumazet, markus, coreyb,
keescook, jmorris
In-Reply-To: <1333051320-30872-9-git-send-email-wad@chromium.org>
On Thu, 29 Mar 2012 15:01:53 -0500
Will Drewry <wad@chromium.org> wrote:
> [This patch depends on luto@mit.edu's no_new_privs patch:
> https://lkml.org/lkml/2012/1/30/264
> included in this series for ease of consumption.
> ]
>
> This patch adds support for seccomp mode 2. Mode 2 introduces the
> ability for unprivileged processes to install system call filtering
> policy expressed in terms of a Berkeley Packet Filter (BPF) program.
> This program will be evaluated in the kernel for each system call
> the task makes and computes a result based on data in the format
> of struct seccomp_data.
>
> A filter program may be installed by calling:
> struct sock_fprog fprog = { ... };
> ...
> prctl(PR_SET_SECCOMP, SECCOMP_MODE_FILTER, &fprog);
>
> The return value of the filter program determines if the system call is
> allowed to proceed or denied. If the first filter program installed
> allows prctl(2) calls, then the above call may be made repeatedly
> by a task to further reduce its access to the kernel. All attached
> programs must be evaluated before a system call will be allowed to
> proceed.
>
> Filter programs will be inherited across fork/clone and execve.
> However, if the task attaching the filter is unprivileged
> (!CAP_SYS_ADMIN) the no_new_privs bit will be set on the task. This
> ensures that unprivileged tasks cannot attach filters that affect
> privileged tasks (e.g., setuid binary).
>
> There are a number of benefits to this approach. A few of which are
> as follows:
> - BPF has been exposed to userland for a long time
> - BPF optimization (and JIT'ing) are well understood
> - Userland already knows its ABI: system call numbers and desired
> arguments
> - No time-of-check-time-of-use vulnerable data accesses are possible.
> - system call arguments are loaded on access only to minimize copying
> required for system call policy decisions.
>
> Mode 2 support is restricted to architectures that enable
> HAVE_ARCH_SECCOMP_FILTER. In this patch, the primary dependency is on
> syscall_get_arguments(). The full desired scope of this feature will
> add a few minor additional requirements expressed later in this series.
> Based on discussion, SECCOMP_RET_ERRNO and SECCOMP_RET_TRACE seem to be
> the desired additional functionality.
>
> No architectures are enabled in this patch.
>
>
> ...
>
> +/**
> + * struct seccomp_filter - container for seccomp BPF programs
> + *
> + * @usage: reference count to manage the object liftime.
i found a bug
> + * get/put helpers should be used when accessing an instance
> + * outside of a lifetime-guarded section. In general, this
> + * is only needed for handling filters shared across tasks.
> + * @prev: points to a previously installed, or inherited, filter
> + * @len: the number of instructions in the program
> + * @insns: the BPF program instructions to evaluate
> + *
> + * seccomp_filter objects are organized in a tree linked via the @prev
> + * pointer. For any task, it appears to be a singly-linked list starting
> + * with current->seccomp.filter, the most recently attached or inherited filter.
> + * However, multiple filters may share a @prev node, by way of fork(), which
> + * results in a unidirectional tree existing in memory. This is similar to
> + * how namespaces work.
> + *
> + * seccomp_filter objects should never be modified after being attached
> + * to a task_struct (other than @usage).
> + */
> +struct seccomp_filter {
> + atomic_t usage;
> + struct seccomp_filter *prev;
> + unsigned short len; /* Instruction count */
> + struct sock_filter insns[];
> +};
> +
> +/* Limit any path through the tree to 256KB worth of instructions. */
> +#define MAX_INSNS_PER_PATH ((1 << 18) / sizeof(struct sock_filter))
> +
> +static void seccomp_filter_log_failure(int syscall)
> +{
> + int compat = 0;
> +#ifdef CONFIG_COMPAT
> + compat = is_compat_task();
> +#endif
hm, I'm surprised that we don't have a zero-returning implementation of
is_compat_task() when CONFIG_COMPAT=n. Seems silly. Blames Arnd.
> + pr_info("%s[%d]: %ssystem call %d blocked at 0x%lx\n",
> + current->comm, task_pid_nr(current),
> + (compat ? "compat " : ""),
> + syscall, KSTK_EIP(current));
> +}
> +
> +/**
> + * get_u32 - returns a u32 offset into data
> + * @data: a unsigned 64 bit value
> + * @index: 0 or 1 to return the first or second 32-bits
> + *
> + * This inline exists to hide the length of unsigned long.
> + * If a 32-bit unsigned long is passed in, it will be extended
> + * and the top 32-bits will be 0. If it is a 64-bit unsigned
> + * long, then whatever data is resident will be properly returned.
> + */
> +static inline u32 get_u32(u64 data, int index)
> +{
> + return ((u32 *)&data)[index];
> +}
This seems utterly broken on big-endian machines. If so: fix. If not:
add comment explaining why?
>
> ...
>
> +/**
> + * seccomp_chk_filter - verify seccomp filter code
> + * @filter: filter to verify
> + * @flen: length of filter
> + *
> + * Takes a previously checked filter (by sk_chk_filter) and
> + * redirects all filter code that loads struct sk_buff data
> + * and related data through seccomp_bpf_load. It also
> + * enforces length and alignment checking of those loads.
> + *
> + * Returns 0 if the rule set is legal or -EINVAL if not.
> + */
> +static int seccomp_chk_filter(struct sock_filter *filter, unsigned int flen)
> +{
> + int pc;
> + for (pc = 0; pc < flen; pc++) {
> + struct sock_filter *ftest = &filter[pc];
> + u16 code = ftest->code;
> + u32 k = ftest->k;
> + switch (code) {
It's conventional to have a blank line between end-of-locals and
start-of-code.
> + case BPF_S_LD_W_ABS:
> + ftest->code = BPF_S_ANC_SECCOMP_LD_W;
> + /* 32-bit aligned and not out of bounds. */
> + if (k >= sizeof(struct seccomp_data) || k & 3)
> + return -EINVAL;
>
> ...
>
> +static u32 seccomp_run_filters(int syscall)
> +{
> + struct seccomp_filter *f;
> + u32 ret = SECCOMP_RET_KILL;
> + /*
> + * All filters are evaluated in order of youngest to oldest. The lowest
> + * BPF return value always takes priority.
> + */
The youngest-first design surprised me. It wasn't mentioned at all in
the changelog. Thinking about it, I guess it just doesn't matter. But
some description of the reasons for and implications of this decision
for the uninitiated would be welcome.
> + for (f = current->seccomp.filter; f; f = f->prev) {
> + ret = sk_run_filter(NULL, f->insns);
> + if (ret != SECCOMP_RET_ALLOW)
> + break;
> + }
> + return ret;
> +}
> +
> +/**
> + * seccomp_attach_filter: Attaches a seccomp filter to current.
> + * @fprog: BPF program to install
> + *
> + * Returns 0 on success or an errno on failure.
> + */
> +static long seccomp_attach_filter(struct sock_fprog *fprog)
> +{
> + struct seccomp_filter *filter;
> + unsigned long fp_size = fprog->len * sizeof(struct sock_filter);
> + unsigned long total_insns = fprog->len;
> + long ret;
> +
> + if (fprog->len == 0 || fprog->len > BPF_MAXINSNS)
> + return -EINVAL;
> +
> + for (filter = current->seccomp.filter; filter; filter = filter->prev)
> + total_insns += filter->len + 4; /* include a 4 instr penalty */
So tasks don't share filters? We copy them by value at fork? Do we do
this at vfork() too?
> + if (total_insns > MAX_INSNS_PER_PATH)
> + return -ENOMEM;
> +
> + /*
> + * Installing a seccomp filter requires that the task have
> + * CAP_SYS_ADMIN in its namespace or be running with no_new_privs.
> + * This avoids scenarios where unprivileged tasks can affect the
> + * behavior of privileged children.
> + */
> + if (!current->no_new_privs &&
> + security_capable_noaudit(current_cred(), current_user_ns(),
> + CAP_SYS_ADMIN) != 0)
> + return -EACCES;
> +
> + /* Allocate a new seccomp_filter */
> + filter = kzalloc(sizeof(struct seccomp_filter) + fp_size, GFP_KERNEL);
I think this gives userspace an easy way of causing page allocation
failure warnings, by permitting large kmalloc() attempts. Add
__GFP_NOWARN?
> + if (!filter)
> + return -ENOMEM;
> + atomic_set(&filter->usage, 1);
> + filter->len = fprog->len;
> +
> + /* Copy the instructions from fprog. */
> + ret = -EFAULT;
> + if (copy_from_user(filter->insns, fprog->filter, fp_size))
> + goto fail;
> +
> + /* Check and rewrite the fprog via the skb checker */
> + ret = sk_chk_filter(filter->insns, filter->len);
> + if (ret)
> + goto fail;
> +
> + /* Check and rewrite the fprog for seccomp use */
> + ret = seccomp_chk_filter(filter->insns, filter->len);
"check" is spelled "check"!
> + if (ret)
> + goto fail;
> +
> + /*
> + * If there is an existing filter, make it the prev and don't drop its
> + * task reference.
> + */
> + filter->prev = current->seccomp.filter;
> + current->seccomp.filter = filter;
> + return 0;
> +fail:
> + kfree(filter);
> + return ret;
> +}
> +
>
> ...
>
> +/* put_seccomp_filter - decrements the ref count of tsk->seccomp.filter */
> +void put_seccomp_filter(struct task_struct *tsk)
> +{
> + struct seccomp_filter *orig = tsk->seccomp.filter;
> + /* Clean up single-reference branches iteratively. */
> + while (orig && atomic_dec_and_test(&orig->usage)) {
> + struct seccomp_filter *freeme = orig;
> + orig = orig->prev;
> + kfree(freeme);
> + }
> +}
So if one of the filters in the list has an elevated refcount, we bail
out on the remainder of the list. Seems odd.
> +#endif /* CONFIG_SECCOMP_FILTER */
>
> ...
>
^ permalink raw reply
* Re: [PATCH v17 01/15] Add PR_{GET,SET}_NO_NEW_PRIVS to prevent execve from granting privs
From: Jonathan Corbet @ 2012-04-06 20:28 UTC (permalink / raw)
To: Andrew Lutomirski
Cc: Andrew Morton, Will Drewry, linux-kernel, linux-security-module,
linux-arch, linux-doc, kernel-hardening, netdev, x86, arnd, davem,
hpa, mingo, oleg, peterz, rdunlap, mcgrathr, tglx, eparis,
serge.hallyn, djm, scarybeasts, indan, pmoore, eric.dumazet,
markus, coreyb, keescook, jmorris, Andy Lutomirski, linux-man
In-Reply-To: <CAObL_7EYb62o=a0ekzcDx=0TuN55A7aTYhLJbMNu2r8F0V77EA@mail.gmail.com>
On Fri, 6 Apr 2012 13:01:17 -0700
Andrew Lutomirski <luto@mit.edu> wrote:
> This has been bugging me for awhile. Is there any interest in moving
> the manpages into the kernel source tree? Then there could be a
> general requirement that new APIs get documented when they're written.
Man page (or other documentation) requirements for patch acceptance are a
regular kernel summit feature. People seem to think it's a good idea, but
actual enforcement of such requirements always seems to be lacking. Lots
of people have kind of given up trying. I don't really see that adding
the man pages to the tree would help, but I could be wrong...
jon
^ permalink raw reply
* Re: [PATCH v17 01/15] Add PR_{GET,SET}_NO_NEW_PRIVS to prevent execve from granting privs
From: Andrew Lutomirski @ 2012-04-06 20:37 UTC (permalink / raw)
To: Jonathan Corbet
Cc: Andrew Morton, Will Drewry, linux-kernel, linux-security-module,
linux-arch, linux-doc, kernel-hardening, netdev, x86, arnd, davem,
hpa, mingo, oleg, peterz, rdunlap, mcgrathr, tglx, eparis,
serge.hallyn, djm, scarybeasts, indan, pmoore, eric.dumazet,
markus, coreyb, keescook, jmorris, Andy Lutomirski, linux-man
In-Reply-To: <20120406142824.61d8ca3b@lwn.net>
On Fri, Apr 6, 2012 at 1:28 PM, Jonathan Corbet <corbet@lwn.net> wrote:
> On Fri, 6 Apr 2012 13:01:17 -0700
> Andrew Lutomirski <luto@mit.edu> wrote:
>
>> This has been bugging me for awhile. Is there any interest in moving
>> the manpages into the kernel source tree? Then there could be a
>> general requirement that new APIs get documented when they're written.
>
> Man page (or other documentation) requirements for patch acceptance are a
> regular kernel summit feature. People seem to think it's a good idea, but
> actual enforcement of such requirements always seems to be lacking. Lots
> of people have kind of given up trying. I don't really see that adding
> the man pages to the tree would help, but I could be wrong...
>
If it's in the source, then I can send it with git format-patch. If
it's out of tree, I have to find the tree, clone the tree, figure out
how to submit, and send separate emails. And then whoever checks that
I documented it has to figure out where I sent it and how to read it
and then try to decide which documentation submission matches which
patch submission.
(Also, if it's in-tree, then I can build the docs from a kernel tree
and have the latest ones. That could be nice.)
--Andy
^ permalink raw reply
* [PATCH 6/6] tilegx network driver: initial support
From: Chris Metcalf @ 2012-04-06 20:42 UTC (permalink / raw)
To: linux-kernel, netdev
In-Reply-To: <201204062059.q36KxjEO011317@farm-0027.internal.tilera.com>
This change adds support for the tilegx network driver based on the
GXIO IORPC support in the tilegx software stack, using the on-chip
mPIPE packet processing engine.
Signed-off-by: Chris Metcalf <cmetcalf@tilera.com>
---
drivers/net/ethernet/tile/Kconfig | 1 +
drivers/net/ethernet/tile/Makefile | 4 +-
drivers/net/ethernet/tile/tilegx.c | 2045 ++++++++++++++++++++++++++++++++++++
3 files changed, 2048 insertions(+), 2 deletions(-)
create mode 100644 drivers/net/ethernet/tile/tilegx.c
diff --git a/drivers/net/ethernet/tile/Kconfig b/drivers/net/ethernet/tile/Kconfig
index 2d9218f..9184b61 100644
--- a/drivers/net/ethernet/tile/Kconfig
+++ b/drivers/net/ethernet/tile/Kconfig
@@ -7,6 +7,7 @@ config TILE_NET
depends on TILE
default y
select CRC32
+ select TILE_GXIO_MPIPE if TILEGX
---help---
This is a standard Linux network device driver for the
on-chip Tilera Gigabit Ethernet and XAUI interfaces.
diff --git a/drivers/net/ethernet/tile/Makefile b/drivers/net/ethernet/tile/Makefile
index f634f14..0ef9eef 100644
--- a/drivers/net/ethernet/tile/Makefile
+++ b/drivers/net/ethernet/tile/Makefile
@@ -4,7 +4,7 @@
obj-$(CONFIG_TILE_NET) += tile_net.o
ifdef CONFIG_TILEGX
-tile_net-objs := tilegx.o mpipe.o iorpc_mpipe.o dma_queue.o
+tile_net-y := tilegx.o
else
-tile_net-objs := tilepro.o
+tile_net-y := tilepro.o
endif
diff --git a/drivers/net/ethernet/tile/tilegx.c b/drivers/net/ethernet/tile/tilegx.c
new file mode 100644
index 0000000..cca63e8
--- /dev/null
+++ b/drivers/net/ethernet/tile/tilegx.c
@@ -0,0 +1,2045 @@
+/*
+ * Copyright 2011 Tilera Corporation. All Rights Reserved.
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public License
+ * as published by the Free Software Foundation, version 2.
+ *
+ * This program is distributed in the hope that it will be useful, but
+ * WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY OR FITNESS FOR A PARTICULAR PURPOSE, GOOD TITLE or
+ * NON INFRINGEMENT. See the GNU General Public License for
+ * more details.
+ */
+
+#include <linux/module.h>
+#include <linux/init.h>
+#include <linux/moduleparam.h>
+#include <linux/sched.h>
+#include <linux/kernel.h> /* printk() */
+#include <linux/slab.h> /* kmalloc() */
+#include <linux/errno.h> /* error codes */
+#include <linux/types.h> /* size_t */
+#include <linux/interrupt.h>
+#include <linux/in.h>
+#include <linux/irq.h>
+#include <linux/netdevice.h> /* struct device, and other headers */
+#include <linux/etherdevice.h> /* eth_type_trans */
+#include <linux/skbuff.h>
+#include <linux/ioctl.h>
+#include <linux/cdev.h>
+#include <linux/hugetlb.h>
+#include <linux/in6.h>
+#include <linux/timer.h>
+#include <linux/io.h>
+#include <linux/ctype.h>
+#include <asm/checksum.h>
+#include <asm/homecache.h>
+
+#include <gxio/mpipe.h>
+
+/* For TSO */
+#include <linux/ip.h>
+#include <linux/tcp.h>
+
+
+#include <arch/sim.h>
+
+
+/* #define USE_SIM_PRINTF */
+
+#ifdef USE_SIM_PRINTF
+
+static __attribute__((unused, format (printf, 1, 2))) void
+sim_printf(const char *format, ...)
+{
+ char *str;
+ char buf[1024];
+
+ va_list args;
+ va_start(args, format);
+ (void)vsnprintf(buf, sizeof(buf), format, args);
+ va_end(args);
+
+ /* NOTE: Copied from "sim_print()". */
+ for (str = buf; *str != '\0'; str++) {
+ __insn_mtspr(SPR_SIM_CONTROL, SIM_CONTROL_PUTC |
+ (*str << _SIM_CONTROL_OPERATOR_BITS));
+ }
+ __insn_mtspr(SPR_SIM_CONTROL, SIM_CONTROL_PUTC |
+ (SIM_PUTC_FLUSH_BINARY << _SIM_CONTROL_OPERATOR_BITS));
+}
+
+
+/* HACK: Allow use of "sim_printf()" instead of "printk()". */
+#define printk sim_printf
+
+#endif
+
+
+/* First, "tile_net_init_module()" initializes each network cpu to
+ * handle incoming packets, and initializes all the network devices.
+ *
+ * Then, "ifconfig DEVICE up" calls "tile_net_open()", which will
+ * turn on packet processing, if needed.
+ *
+ * If "ifconfig DEVICE down" is called, it uses "tile_net_stop()" to
+ * stop egress, and possibly turn off packet processing.
+ *
+ * We start out with the ingress IRQ enabled on each CPU. When it
+ * fires, it is automatically disabled, and we call "napi_schedule()".
+ * This will cause "tile_net_poll()" to be called, which will pull
+ * packets from the netio queue, filtering them out, or passing them
+ * to "netif_receive_skb()". If our budget is exhausted, we will
+ * return, knowing we will be called again later. Otherwise, we
+ * reenable the ingress IRQ, and call "napi_complete()".
+ *
+ *
+ * NOTE: Failing to free completions for an arbitrarily long time
+ * (which is defined to be illegal) does in fact cause bizarre problems.
+ *
+ * NOTE: The egress code can be interrupted by the interrupt handler.
+ */
+
+
+/* HACK: Define to support GSO.
+ * ISSUE: This may actually hurt performance of the TCP blaster.
+ */
+#undef TILE_NET_GSO
+
+/* HACK: Define to support TSO. */
+#define TILE_NET_TSO
+
+/* Use 3000 to enable the Linux Traffic Control (QoS) layer, else 0. */
+#define TILE_NET_TX_QUEUE_LEN 0
+
+/* Define to dump packets (prints out the whole packet on tx and rx). */
+#undef TILE_NET_DUMP_PACKETS
+
+/* Define to use "round robin" distribution. */
+#undef TILE_NET_ROUND_ROBIN
+
+/* Default transmit lockup timeout period, in jiffies. */
+#define TILE_NET_TIMEOUT (5 * HZ)
+
+/* The number of distinct channels. */
+#define TILE_NET_CHANNELS (MPIPE_NUM_SGMII_MACS + MPIPE_NUM_LOOPBACK_CHANNELS)
+
+/* The max number of distinct devices ("xgbe" shares the "gbe" channels). */
+#define TILE_NET_DEVS (TILE_NET_CHANNELS + MPIPE_NUM_XAUI_MACS)
+
+/* Maximum number of idescs to handle per "poll". */
+#define TILE_NET_BATCH 128
+
+/* Maximum number of packets to handle per "poll". */
+#define TILE_NET_WEIGHT 64
+
+/* Number of entries in each iqueue. */
+#define IQUEUE_ENTRIES 512
+
+/* Number of entries in each equeue. */
+#define EQUEUE_ENTRIES 2048
+
+/* Total header bytes per equeue slot. Must be big enough for 2 bytes
+ * of NET_IP_ALIGN alignment, plus 14 bytes (?) of L2 header, plus up to
+ * 60 bytes of actual TCP header. We round up to align to cache lines.
+ */
+#define HEADER_BYTES 128
+
+/* Maximum completions per cpu per device (must be a power of two).
+ * ISSUE: What is the right number here?
+ */
+#define TILE_NET_MAX_COMPS 64
+
+
+#define ROUND_UP(n, align) (((n) + (align) - 1) & -(align))
+
+
+#define MAX_FRAGS (65536 / PAGE_SIZE + 2 + 1)
+
+
+MODULE_AUTHOR("Tilera");
+MODULE_LICENSE("GPL");
+
+
+
+/* A "packet fragment" (a chunk of memory). */
+struct frag {
+ void *buf;
+ size_t length;
+};
+
+
+/* Statistics counters for a specific cpu and device. */
+struct tile_net_stats_t {
+ u32 rx_packets;
+ u32 rx_bytes;
+ u32 tx_packets;
+ u32 tx_bytes;
+};
+
+
+/* A single completion. */
+struct tile_net_comp {
+ /* The "complete_count" when the completion will be complete. */
+ s64 when;
+ /* The buffer to be freed when the completion is complete. */
+ struct sk_buff *skb;
+};
+
+
+/* The completions for a given cpu and device. */
+struct tile_net_comps {
+ /* The completions. */
+ struct tile_net_comp comp_queue[TILE_NET_MAX_COMPS];
+ /* The number of completions used. */
+ unsigned long comp_next;
+ /* The number of completions freed. */
+ unsigned long comp_last;
+};
+
+
+/* Info for a specific cpu.
+ *
+ * ISSUE: Should "comps" be per channel instead of per dev?
+ */
+struct tile_net_info_t {
+ /* The NAPI struct. */
+ struct napi_struct napi;
+ /* Packet queue. */
+ gxio_mpipe_iqueue_t iqueue;
+ /* Our cpu. */
+ int my_cpu;
+ /* True if iqueue is valid. */
+ bool has_iqueue;
+ /* NAPI flags. */
+ bool napi_added;
+ bool napi_enabled;
+ /* Number of small sk_buffs which must still be provided. */
+ unsigned int num_needed_small_buffers;
+ /* Number of large sk_buffs which must still be provided. */
+ unsigned int num_needed_large_buffers;
+ /* A timer for handling egress completions. */
+ struct timer_list egress_timer;
+ /* True if "egress_timer" is scheduled. */
+ bool egress_timer_scheduled;
+ /* Comps for each device. */
+ struct tile_net_comps *comps_for_dev[TILE_NET_DEVS];
+ /* Stats for each device. */
+ struct tile_net_stats_t stats_for_dev[TILE_NET_DEVS];
+};
+
+
+/* Info for a specific device. */
+struct tile_net_priv {
+ /* Our network device. */
+ struct net_device *dev;
+ /* Our "devno". */
+ int devno;
+ /* The primary link. */
+ gxio_mpipe_link_t link;
+ /* The primary channel, if open, else -1. */
+ int channel;
+ /* The "loopify" egress link, if needed. */
+ gxio_mpipe_link_t loopify_link;
+ /* The "loopify" egress channel, if open, else -1. */
+ int loopify_channel;
+ /* Total stats. */
+ struct net_device_stats stats;
+ /* The (lazy) "equeue". */
+ gxio_mpipe_equeue_t *equeue;
+ /* The (lazy) headers for TSO. */
+ unsigned char *headers;
+};
+
+
+/* The actual devices. */
+static struct net_device *tile_net_devs[TILE_NET_DEVS];
+
+/* The device for a given channel. HACK: We use "32", not
+ * TILE_NET_CHANNELS, because it is fairly subtle that the 5 bit
+ * "idesc.channel" field never exceeds TILE_NET_CHANNELS.
+ */
+static struct net_device *tile_net_devs_for_channel[32];
+
+/* A mutex for "tile_net_devs_for_channel". */
+static struct mutex tile_net_devs_mutex;
+
+/* The per-cpu info. */
+static DEFINE_PER_CPU(struct tile_net_info_t, per_cpu_info);
+
+/* Access to "per_cpu_info". */
+static struct tile_net_info_t *infos[NR_CPUS];
+
+/* The "context" for all devices. */
+static gxio_mpipe_context_t context;
+
+/* The small/large "buffer stacks". */
+static int small_buffer_stack = -1;
+static int large_buffer_stack = -1;
+
+/* The buckets. */
+static int first_bucket = -1;
+static int num_buckets = 1;
+
+/* The ingress irq. */
+static int ingress_irq = -1;
+
+
+/* True if "network_cpus" was specified. */
+static bool network_cpus_used;
+
+/* The actual cpus in "network_cpus". */
+static struct cpumask network_cpus_map;
+
+
+/* If "loopify=LINK" was specified, this is "LINK". */
+static char loopify_link_name[16];
+
+
+
+#ifdef TILE_NET_DUMP_PACKETS
+/* Dump a packet. */
+static void dump_packet(unsigned char *data, unsigned long length, char *s)
+{
+ unsigned long i;
+ static unsigned int count;
+ char buf[128];
+
+ pr_info("Dumping %s packet of 0x%lx bytes at %p [%d]\n",
+ s, length, data, count++);
+
+ pr_info("\n");
+
+ for (i = 0; i < length; i++) {
+ if ((i & 0xf) == 0)
+ sprintf(buf, "%8.8lx:", i);
+ sprintf(buf + strlen(buf), " %02x", data[i]);
+ if ((i & 0xf) == 0xf || i == length - 1)
+ pr_info("%s\n", buf);
+ }
+
+ pr_info("\n");
+}
+#endif
+
+
+/* Convert a "buffer ptr" into a "buffer cpa". */
+static inline void *buf_to_cpa(void *buf)
+{
+ return (void *)__pa(buf);
+}
+
+
+/* Convert a "buffer cpa" into a "buffer ptr". */
+static inline void *cpa_to_buf(void *cpa)
+{
+ return (void *)__va(cpa);
+}
+
+
+
+/* Allocate and push a buffer. */
+static bool tile_net_provide_buffer(bool small)
+{
+ int stack = small ? small_buffer_stack : large_buffer_stack;
+
+ /* Buffers must be aligned. */
+ const unsigned long align = 128;
+
+ /* Note that "dev_alloc_skb()" adds NET_SKB_PAD more bytes,
+ * and also "reserves" that many bytes.
+ */
+ int len = sizeof(struct sk_buff **) + align + (small ? 128 : 1664);
+
+ /* Allocate (or fail). */
+ struct sk_buff *skb = dev_alloc_skb(len);
+ if (skb == NULL)
+ return false;
+
+ /* Make room for a back-pointer to 'skb'. */
+ skb_reserve(skb, sizeof(struct sk_buff **));
+
+ /* Make sure we are aligned. */
+ skb_reserve(skb, -(long)skb->data & (align - 1));
+
+ /* Save a back-pointer to 'skb'. */
+ *(struct sk_buff **)(skb->data - sizeof(struct sk_buff **)) = skb;
+
+ /* Make sure "skb" and the back-pointer have been flushed. */
+ __insn_mf();
+
+ gxio_mpipe_push_buffer(&context, stack, buf_to_cpa(skb->data));
+
+ return true;
+}
+
+
+/* Provide linux buffers to mPIPE. */
+static void tile_net_provide_needed_buffers(struct tile_net_info_t *info)
+{
+ while (info->num_needed_small_buffers != 0) {
+ if (!tile_net_provide_buffer(true))
+ goto oops;
+ info->num_needed_small_buffers--;
+ }
+
+ while (info->num_needed_large_buffers != 0) {
+ if (!tile_net_provide_buffer(false))
+ goto oops;
+ info->num_needed_large_buffers--;
+ }
+
+ return;
+
+oops:
+
+ /* Add a description to the page allocation failure dump. */
+ pr_notice("Tile %d still needs some buffers\n", info->my_cpu);
+}
+
+
+/* Handle a packet. Return true if "processed", false if "filtered". */
+static bool tile_net_handle_packet(struct tile_net_info_t *info,
+ gxio_mpipe_idesc_t *idesc)
+{
+ /* NOTE: This can be NULL during shutdown. */
+ struct net_device *dev = tile_net_devs_for_channel[idesc->channel];
+
+ void *va;
+
+ uint8_t l2_offset = gxio_mpipe_idesc_get_l2_offset(idesc);
+
+ void *buf;
+ unsigned long len;
+
+ int filter = 0;
+
+ /* Drop packets for which no buffer was available.
+ * NOTE: This happens under heavy load.
+ */
+ if (idesc->be) {
+ gxio_mpipe_iqueue_consume(&info->iqueue, idesc);
+ if (net_ratelimit())
+ pr_info("Dropping packet (insufficient buffers).\n");
+ return false;
+ }
+
+ /* Get the raw buffer VA. */
+ va = cpa_to_buf(gxio_mpipe_idesc_get_va(idesc));
+
+ /* Get the actual packet start/length. */
+ buf = va + l2_offset;
+ len = gxio_mpipe_idesc_get_l2_length(idesc);
+
+ /* Point "va" at the raw buffer. */
+ va -= NET_IP_ALIGN;
+
+#ifdef TILE_NET_DUMP_PACKETS
+ dump_packet(buf, len, "rx");
+#endif /* TILE_NET_DUMP_PACKETS */
+
+ if (dev != NULL) {
+ /* ISSUE: Is this needed? */
+ dev->last_rx = jiffies;
+ }
+
+ if (dev == NULL || !(dev->flags & IFF_UP)) {
+ /* Filter packets received before we're up. */
+ filter = 1;
+ } else if (!(dev->flags & IFF_PROMISC)) {
+ /* ISSUE: "eth_type_trans()" implies that "IFF_PROMISC"
+ * is set for "all silly devices", however, it appears
+ * to NOT be set for us, so this code here DOES run.
+ * FIXME: The classifier will soon detect "multicast".
+ */
+ if (!is_multicast_ether_addr(buf)) {
+ /* Filter packets not for our address. */
+ const u8 *mine = dev->dev_addr;
+ filter = compare_ether_addr(mine, buf);
+ }
+ }
+
+ if (filter) {
+
+ /* ISSUE: Update "drop" statistics? */
+
+ gxio_mpipe_iqueue_drop(&info->iqueue, idesc);
+
+ } else {
+
+ struct tile_net_priv *priv = netdev_priv(dev);
+ struct tile_net_stats_t *stats =
+ &info->stats_for_dev[priv->devno];
+
+ /* Acquire the associated "skb". */
+ struct sk_buff **skb_ptr = va - sizeof(*skb_ptr);
+ struct sk_buff *skb = *skb_ptr;
+
+ /* Paranoia. */
+ if (skb->data != va)
+ panic("Corrupt linux buffer! "
+ "buf=%p, skb=%p, skb->data=%p\n",
+ buf, skb, skb->data);
+
+ /* Skip headroom, and any custom header. */
+ skb_reserve(skb, NET_IP_ALIGN + l2_offset);
+
+ /* Encode the actual packet length. */
+ skb_put(skb, len);
+
+ /* NOTE: This call also sets "skb->dev = dev".
+ * ISSUE: The classifier provides us with "eth_type"
+ * (aka "eth->h_proto"), which is basically the value
+ * returned by "eth_type_trans()".
+ * Note that "eth_type_trans()" computes "skb->pkt_type",
+ * which would be useful for the "filter" check above,
+ * if we had a (modifiable) "skb" to work with.
+ */
+ skb->protocol = eth_type_trans(skb, dev);
+
+ /* Acknowledge "good" hardware checksums. */
+ if (idesc->cs && idesc->csum_seed_val == 0xFFFF)
+ skb->ip_summed = CHECKSUM_UNNECESSARY;
+
+ netif_receive_skb(skb);
+
+ /* Update stats. */
+ stats->rx_packets++;
+ stats->rx_bytes += len;
+
+ /* Need a new buffer. */
+ if (idesc->size == GXIO_MPIPE_BUFFER_SIZE_128)
+ info->num_needed_small_buffers++;
+ else
+ info->num_needed_large_buffers++;
+ }
+
+ gxio_mpipe_iqueue_consume(&info->iqueue, idesc);
+
+ return !filter;
+}
+
+
+/* Handle some packets for the current CPU.
+ *
+ * This function handles up to TILE_NET_BATCH idescs per call.
+ *
+ * ISSUE: Since we do not provide new buffers until this function is
+ * complete, we must initially provide enough buffers for each network
+ * cpu to fill its iqueue and also its batched idescs.
+ *
+ * ISSUE: The "rotting packet" race condition occurs if a packet
+ * arrives after the queue appears to be empty, and before the
+ * hypervisor interrupt is re-enabled.
+ */
+static int tile_net_poll(struct napi_struct *napi, int budget)
+{
+ struct tile_net_info_t *info = &__get_cpu_var(per_cpu_info);
+
+ unsigned int work = 0;
+
+ gxio_mpipe_idesc_t *idesc;
+ int i, n;
+
+ /* Process packets. */
+ while ((n = gxio_mpipe_iqueue_try_peek(&info->iqueue, &idesc)) > 0) {
+ for (i = 0; i < n; i++) {
+ if (i == TILE_NET_BATCH)
+ goto done;
+ if (tile_net_handle_packet(info, idesc + i)) {
+ if (++work >= budget)
+ goto done;
+ }
+ }
+ }
+
+ /* There are no packets left. */
+ napi_complete(&info->napi);
+
+ /* Re-enable hypervisor interrupts. */
+ gxio_mpipe_enable_notif_ring_interrupt(&context, info->iqueue.ring);
+
+ /* HACK: Avoid the "rotting packet" problem. */
+ if (gxio_mpipe_iqueue_try_peek(&info->iqueue, &idesc) > 0)
+ napi_schedule(&info->napi);
+
+ /* ISSUE: Handle completions? */
+
+done:
+
+ tile_net_provide_needed_buffers(info);
+
+ return work;
+}
+
+
+/* Handle an ingress interrupt on the current cpu. */
+static irqreturn_t tile_net_handle_ingress_irq(int irq, void *unused)
+{
+ struct tile_net_info_t *info = &__get_cpu_var(per_cpu_info);
+ napi_schedule(&info->napi);
+ return IRQ_HANDLED;
+}
+
+
+/* Free some completions. This must be called with interrupts blocked. */
+static void tile_net_free_comps(struct net_device *dev,
+ struct tile_net_comps *comps,
+ int limit, bool force_update)
+{
+ struct tile_net_priv *priv = netdev_priv(dev);
+
+ gxio_mpipe_equeue_t *equeue = priv->equeue;
+
+ int n = 0;
+ while (comps->comp_last < comps->comp_next) {
+ unsigned int cid = comps->comp_last % TILE_NET_MAX_COMPS;
+ struct tile_net_comp *comp = &comps->comp_queue[cid];
+ if (!gxio_mpipe_equeue_is_complete(equeue, comp->when,
+ force_update || n == 0))
+ return;
+ dev_kfree_skb_irq(comp->skb);
+ comps->comp_last++;
+ if (++n == limit)
+ return;
+ }
+}
+
+
+/* Make sure the egress timer is scheduled.
+ *
+ * Note that we use "schedule if not scheduled" logic instead of the more
+ * obvious "reschedule" logic, because "reschedule" is fairly expensive.
+ */
+static void tile_net_schedule_egress_timer(struct tile_net_info_t *info)
+{
+ if (!info->egress_timer_scheduled) {
+ mod_timer_pinned(&info->egress_timer, jiffies + 1);
+ info->egress_timer_scheduled = true;
+ }
+}
+
+
+/* The "function" for "info->egress_timer".
+ *
+ * This timer will reschedule itself as long as there are any pending
+ * completions expected for this tile.
+ */
+static void tile_net_handle_egress_timer(unsigned long arg)
+{
+ struct tile_net_info_t *info = (struct tile_net_info_t *)arg;
+
+ unsigned int k;
+
+ bool pending = false;
+
+ unsigned long irqflags;
+
+ local_irq_save(irqflags);
+
+ /* The timer is no longer scheduled. */
+ info->egress_timer_scheduled = false;
+
+ /* Free all possible comps for this tile. */
+ for (k = 0; k < TILE_NET_DEVS; k++) {
+ struct tile_net_comps *comps = info->comps_for_dev[k];
+ if (comps->comp_last >= comps->comp_next)
+ continue;
+ tile_net_free_comps(tile_net_devs[k], comps, -1, true);
+ pending = pending || (comps->comp_last < comps->comp_next);
+ }
+
+ /* Reschedule timer if needed. */
+ if (pending)
+ tile_net_schedule_egress_timer(info);
+
+ local_irq_restore(irqflags);
+}
+
+
+/* Prepare each CPU. */
+static void tile_net_prepare_cpu(void *unused)
+{
+ struct tile_net_info_t *info = &__get_cpu_var(per_cpu_info);
+
+ int my_cpu = smp_processor_id();
+
+ info->has_iqueue = false;
+
+ info->my_cpu = my_cpu;
+
+ /* Initialize the egress timer. */
+ init_timer(&info->egress_timer);
+ info->egress_timer.data = (long)info;
+ info->egress_timer.function = tile_net_handle_egress_timer;
+
+ infos[my_cpu] = info;
+}
+
+
+/* Helper function for "tile_net_update()". */
+static void tile_net_update_cpu(void *count_ptr)
+{
+ long count = *(long *)count_ptr;
+
+ struct tile_net_info_t *info = &__get_cpu_var(per_cpu_info);
+
+ if (info->has_iqueue) {
+ if (count != 0) {
+ if (!info->napi_added) {
+ /* FIXME: HACK: We use one of the devices.
+ * ISSUE: We never call "netif_napi_del()".
+ */
+ netif_napi_add(tile_net_devs[0], &info->napi,
+ tile_net_poll, TILE_NET_WEIGHT);
+ info->napi_added = true;
+ }
+ if (!info->napi_enabled) {
+ napi_enable(&info->napi);
+ info->napi_enabled = true;
+ }
+ enable_percpu_irq(ingress_irq, 0);
+ } else {
+ disable_percpu_irq(ingress_irq);
+ if (info->napi_enabled) {
+ napi_disable(&info->napi);
+ info->napi_enabled = false;
+ }
+ /* FIXME: Drain the iqueue. */
+ }
+ }
+}
+
+
+/* Helper function for tile_net_open() and tile_net_stop(). */
+static int tile_net_update(void)
+{
+ int channel;
+ long count = 0;
+ int cpu;
+
+ /* HACK: This is too big for the linux stack. */
+ static gxio_mpipe_rules_t rules;
+
+ gxio_mpipe_rules_init(&rules, &context);
+
+ /* TODO: Add support for "dmac" splitting? */
+ for (channel = 0; channel < TILE_NET_DEVS; channel++) {
+ if (tile_net_devs_for_channel[channel] == NULL)
+ continue;
+ if (count++ == 0) {
+ gxio_mpipe_rules_begin(&rules, first_bucket,
+ num_buckets, NULL);
+ gxio_mpipe_rules_set_headroom(&rules, NET_IP_ALIGN);
+ }
+ gxio_mpipe_rules_add_channel(&rules, channel);
+ }
+
+ /* NOTE: This can happen if there is no classifier.
+ * ISSUE: Can anything else cause it to happen?
+ */
+ if (gxio_mpipe_rules_commit(&rules) != 0) {
+ pr_warning("Failed to update classifier rules!\n");
+ return -EIO;
+ }
+
+ /* Update all cpus, sequentially (to protect "netif_napi_add()"). */
+ for_each_online_cpu(cpu)
+ smp_call_function_single(cpu, tile_net_update_cpu, &count, 1);
+
+ /* HACK: Allow packets to flow. */
+ if (count != 0)
+ sim_enable_mpipe_links(0, -1);
+
+ return 0;
+}
+
+
+/* Helper function for "tile_net_init_cpus()". */
+static void tile_net_init_stacks(int network_cpus_count)
+{
+ int err;
+ int i;
+
+ gxio_mpipe_buffer_size_enum_t small_buf_size =
+ GXIO_MPIPE_BUFFER_SIZE_128;
+ gxio_mpipe_buffer_size_enum_t large_buf_size =
+ GXIO_MPIPE_BUFFER_SIZE_1664;
+
+ int num_buffers;
+
+ size_t stack_bytes;
+
+ pte_t pte = { 0 };
+
+ void *mem;
+
+ num_buffers =
+ network_cpus_count * (IQUEUE_ENTRIES + TILE_NET_BATCH);
+
+ /* Compute stack bytes, honoring the 64KB minimum alignment. */
+ stack_bytes = ROUND_UP(gxio_mpipe_calc_buffer_stack_bytes(num_buffers),
+ 64 * 1024);
+ if (stack_bytes > HPAGE_SIZE)
+ panic("Cannot allocate %d physically contiguous buffers.",
+ num_buffers);
+
+#if 0
+ sim_printf("Using %d buffers for %d network cpus.\n",
+ num_buffers, network_cpus_count);
+#endif
+
+ /* Allocate two buffer stacks. */
+ small_buffer_stack = gxio_mpipe_alloc_buffer_stacks(&context, 2, 0, 0);
+ if (small_buffer_stack < 0)
+ panic("Failure in 'gxio_mpipe_alloc_buffer_stacks()'");
+ large_buffer_stack = small_buffer_stack + 1;
+
+ /* Allocate the small memory stack. */
+ mem = alloc_pages_exact(stack_bytes, GFP_KERNEL);
+ if (mem == NULL)
+ panic("Could not allocate buffer memory!");
+ err = gxio_mpipe_init_buffer_stack(&context, small_buffer_stack,
+ small_buf_size,
+ mem, stack_bytes, 0);
+ if (err != 0)
+ panic("Error %d in 'gxio_mpipe_init_buffer_stack()'.", err);
+
+ /* Allocate the large buffer stack. */
+ mem = alloc_pages_exact(stack_bytes, GFP_KERNEL);
+ if (mem == NULL)
+ panic("Could not allocate buffer memory!");
+ err = gxio_mpipe_init_buffer_stack(&context, large_buffer_stack,
+ large_buf_size,
+ mem, stack_bytes, 0);
+ if (err != 0)
+ panic("Error %d in 'gxio_mpipe_init_buffer_stack()'.", err);
+
+ /* Pin all the client memory. */
+ pte = pte_set_home(pte, PAGE_HOME_HASH);
+ err = gxio_mpipe_register_client_memory(&context, small_buffer_stack,
+ pte, 0);
+ if (err != 0)
+ panic("Error %d in 'gxio_mpipe_register_buffer_memory()'.",
+ err);
+ err = gxio_mpipe_register_client_memory(&context, large_buffer_stack,
+ pte, 0);
+ if (err != 0)
+ panic("Error %d in 'gxio_mpipe_register_buffer_memory()'.",
+ err);
+
+ /* Provide initial buffers. */
+ for (i = 0; i < num_buffers; i++) {
+ if (!tile_net_provide_buffer(true))
+ panic("Cannot provide initial buffers!");
+ }
+ for (i = 0; i < num_buffers; i++) {
+ if (!tile_net_provide_buffer(false))
+ panic("Cannot provide initial buffers!");
+ }
+}
+
+
+/* Actually initialize the mPIPE state. */
+static int tile_net_init_cpus(void)
+{
+ int network_cpus_count;
+
+ int ring;
+ int group;
+
+ int next_ring;
+
+ int cpu;
+
+ int i;
+
+#ifdef TILE_NET_ROUND_ROBIN
+ gxio_mpipe_bucket_mode_t mode = GXIO_MPIPE_BUCKET_ROUND_ROBIN;
+#else
+ /* Use random rebalancing. */
+ gxio_mpipe_bucket_mode_t mode = GXIO_MPIPE_BUCKET_STICKY_FLOW_LOCALITY;
+#endif
+
+ if (!hash_default) {
+ pr_warning("Networking requires hash_default!\n");
+ goto fail;
+ }
+
+ if (gxio_mpipe_init(&context, 0) != 0) {
+ pr_warning("Failed to initialize mPIPE!\n");
+ goto fail;
+ }
+
+ if (!network_cpus_used)
+ network_cpus_map = cpu_online_map;
+
+#ifdef CONFIG_DATAPLANE
+ /* Remove dataplane cpus. */
+ cpus_andnot(network_cpus_map, network_cpus_map, dataplane_map);
+#endif
+
+ network_cpus_count = cpus_weight(network_cpus_map);
+
+ /* ISSUE: Handle failures more gracefully. */
+ tile_net_init_stacks(network_cpus_count);
+
+ /* Allocate one NotifRing for each network cpu. */
+ ring = gxio_mpipe_alloc_notif_rings(&context, network_cpus_count,
+ 0, 0);
+ if (ring < 0) {
+ pr_warning("Failed to allocate notif rings.\n");
+ goto fail;
+ }
+
+ /* ISSUE: Handle failures below more cleanly. */
+
+ /* Init NotifRings. */
+ next_ring = ring;
+
+ for_each_online_cpu(cpu) {
+
+ size_t notif_ring_size =
+ IQUEUE_ENTRIES * sizeof(gxio_mpipe_idesc_t);
+
+ int order;
+ struct page *page;
+ void *addr;
+
+ struct tile_net_info_t *info = infos[cpu];
+
+ size_t comps_size =
+ TILE_NET_DEVS * sizeof(struct tile_net_comps);
+
+ /* Allocate the "comps". */
+ order = get_order(comps_size);
+ page = homecache_alloc_pages(GFP_KERNEL, order, cpu);
+ if (page == NULL)
+ panic("Failed to allocate comps memory.");
+ addr = pfn_to_kaddr(page_to_pfn(page));
+ /* ISSUE: Is this needed? */
+ memset(addr, 0, comps_size);
+ for (i = 0; i < TILE_NET_DEVS; i++)
+ info->comps_for_dev[i] =
+ addr + i * sizeof(struct tile_net_comps);
+
+ /* Only network cpus can receive packets. */
+ if (!cpu_isset(cpu, network_cpus_map))
+ continue;
+
+ /* Allocate the actual idescs array. */
+ order = get_order(notif_ring_size);
+ page = homecache_alloc_pages(GFP_KERNEL, order, cpu);
+ if (page == NULL)
+ panic("Failed to allocate iqueue memory.");
+ addr = pfn_to_kaddr(page_to_pfn(page));
+
+ if (gxio_mpipe_iqueue_init(&info->iqueue, &context, next_ring,
+ addr, notif_ring_size, 0) != 0)
+ panic("Failure in 'gxio_mpipe_iqueue_init()'.");
+
+ info->has_iqueue = true;
+
+ next_ring++;
+ }
+
+ /* Allocate one NotifGroup. */
+ group = gxio_mpipe_alloc_notif_groups(&context, 1, 0, 0);
+ if (group < 0)
+ panic("Failure in 'gxio_mpipe_alloc_notif_groups()'.");
+
+#ifndef TILE_NET_ROUND_ROBIN
+ if (network_cpus_count > 4)
+ num_buckets = 256;
+ else if (network_cpus_count > 1)
+ num_buckets = 16;
+#endif
+
+ /* Allocate some buckets. */
+ first_bucket = gxio_mpipe_alloc_buckets(&context, num_buckets, 0, 0);
+ if (first_bucket < 0)
+ panic("Failure in 'gxio_mpipe_alloc_buckets()'.");
+
+ /* Init group and buckets. */
+ if (gxio_mpipe_init_notif_group_and_buckets(&context, group, ring,
+ network_cpus_count,
+ first_bucket, num_buckets,
+ mode) != 0)
+ panic("Fail in 'gxio_mpipe_init_notif_group_and_buckets().");
+
+
+ /* Create an irq and register it. */
+ ingress_irq = create_irq();
+ if (ingress_irq < 0)
+ panic("Failed to create irq for ingress.");
+ tile_irq_activate(ingress_irq, TILE_IRQ_PERCPU);
+ BUG_ON(request_irq(ingress_irq, tile_net_handle_ingress_irq,
+ 0, NULL, NULL) != 0);
+
+ for_each_online_cpu(cpu) {
+
+ struct tile_net_info_t *info = infos[cpu];
+
+ int ring = info->iqueue.ring;
+
+ if (!info->has_iqueue)
+ continue;
+
+ gxio_mpipe_request_notif_ring_interrupt(&context,
+ cpu_x(cpu), cpu_y(cpu),
+ 1, ingress_irq, ring);
+ }
+
+ return 0;
+
+fail:
+ return -EIO;
+}
+
+
+/* Create persistent egress info for a given channel.
+ *
+ * Note that this may be shared between, say, "gbe0" and "xgbe0".
+ */
+static int tile_net_init_egress(struct tile_net_priv *priv)
+{
+ int channel =
+ ((priv->loopify_channel >= 0) ?
+ priv->loopify_channel : priv->channel);
+
+ size_t headers_order;
+ struct page *headers_page;
+ unsigned char* headers;
+
+ size_t edescs_size;
+ int edescs_order;
+ struct page *edescs_page;
+ gxio_mpipe_edesc_t* edescs;
+
+ int equeue_order;
+ struct page *equeue_page;
+ gxio_mpipe_equeue_t* equeue;
+ int edma;
+
+ /* Allocate memory for the "headers".
+ * ISSUE: Defer this until TSO is actually needed?
+ */
+ headers_order = get_order(EQUEUE_ENTRIES * HEADER_BYTES);
+ headers_page = alloc_pages(GFP_KERNEL, headers_order);
+ if (headers_page == NULL) {
+ pr_warning("Could not allocate memory for TSO headers.\n");
+ goto fail;
+ }
+ headers = pfn_to_kaddr(page_to_pfn(headers_page));
+
+ /* Allocate memory for the "edescs". */
+ edescs_size = EQUEUE_ENTRIES * sizeof(*edescs);
+ edescs_order = get_order(edescs_size);
+ edescs_page = alloc_pages(GFP_KERNEL, edescs_order);
+ if (edescs_page == NULL) {
+ pr_warning("Could not allocate memory for eDMA ring.\n");
+ goto fail_headers;
+ }
+ edescs = pfn_to_kaddr(page_to_pfn(edescs_page));
+
+ /* Allocate memory for the "equeue". */
+ equeue_order = get_order(sizeof(*equeue));
+ equeue_page = alloc_pages(GFP_KERNEL, equeue_order);
+ if (equeue_page == NULL) {
+ pr_warning("Could not allocate memory for equeue info.\n");
+ goto fail_edescs;
+ }
+ equeue = pfn_to_kaddr(page_to_pfn(equeue_page));
+
+ /* Allocate an edma ring. */
+ edma = gxio_mpipe_alloc_edma_rings(&context, 1, 0, 0);
+ if (edma < 0) {
+ pr_warning("Could not allocate edma ring.\n");
+ goto fail_equeue;
+ }
+
+ /* Initialize the equeue. This should not fail. */
+ if (gxio_mpipe_equeue_init(equeue, &context, edma, channel,
+ edescs, edescs_size, 0) != 0)
+ panic("Failure in 'gxio_mpipe_equeue_init()'.");
+
+ /* Done. */
+ priv->equeue = equeue;
+ priv->headers = headers;
+ return 0;
+
+fail_equeue:
+ __free_pages(equeue_page, equeue_order);
+
+fail_edescs:
+ __free_pages(edescs_page, edescs_order);
+
+fail_headers:
+ __free_pages(headers_page, headers_order);
+
+fail:
+ return -EIO;
+}
+
+
+/* Help the kernel activate the given network interface. */
+static int tile_net_open(struct net_device *dev)
+{
+ struct tile_net_priv *priv = netdev_priv(dev);
+
+ /* Determine if this is the "loopify" device. */
+ bool loopify = !strcmp(dev->name, loopify_link_name);
+
+ int result;
+
+ mutex_lock(&tile_net_devs_mutex);
+
+ if (ingress_irq < 0) {
+ result = tile_net_init_cpus();
+ if (result != 0)
+ goto fail;
+ }
+
+ if (priv->channel < 0) {
+ const char* ln = loopify ? "loop0" : dev->name;
+ if (gxio_mpipe_link_open(&priv->link, &context, ln, 0) < 0) {
+ netdev_err(dev, "Failed to open '%s'.\n", ln);
+ result = -EIO;
+ goto fail;
+ }
+ priv->channel = gxio_mpipe_link_channel(&priv->link);
+ BUG_ON(priv->channel < 0 || priv->channel >= 32);
+ }
+
+ if (loopify && priv->loopify_channel < 0) {
+ if (gxio_mpipe_link_open(&priv->loopify_link,
+ &context, "loop1", 0) < 0) {
+ netdev_err(dev, "Failed to open 'loop1'.\n");
+ result = -EIO;
+ goto fail;
+ }
+ priv->loopify_channel =
+ gxio_mpipe_link_channel(&priv->loopify_link);
+ BUG_ON(priv->loopify_channel < 0);
+ }
+
+ /* Initialize egress info (if needed). */
+ if (priv->equeue == NULL) {
+ result = tile_net_init_egress(priv);
+ if (result != 0)
+ goto fail;
+ }
+
+ tile_net_devs_for_channel[priv->channel] = dev;
+
+ result = tile_net_update();
+ if (result != 0)
+ goto fail_channel;
+
+ mutex_unlock(&tile_net_devs_mutex);
+
+ /* Start our transmit queue. */
+ netif_start_queue(dev);
+
+ netif_carrier_on(dev);
+
+ return 0;
+
+fail_channel:
+ tile_net_devs_for_channel[priv->channel] = NULL;
+
+fail:
+ if (priv->loopify_channel >= 0) {
+ if (gxio_mpipe_link_close(&priv->loopify_link) != 0)
+ pr_warning("Failed to close loopify link!\n");
+ else
+ priv->loopify_channel = -1;
+ }
+ if (priv->channel >= 0) {
+ if (gxio_mpipe_link_close(&priv->link) != 0)
+ pr_warning("Failed to close link!\n");
+ else
+ priv->channel = -1;
+ }
+
+ mutex_unlock(&tile_net_devs_mutex);
+ return result;
+}
+
+
+
+/* Help the kernel deactivate the given network interface. */
+static int tile_net_stop(struct net_device *dev)
+{
+ struct tile_net_priv *priv = netdev_priv(dev);
+
+ /* Stop our transmit queue. */
+ netif_stop_queue(dev);
+
+ mutex_lock(&tile_net_devs_mutex);
+
+ tile_net_devs_for_channel[priv->channel] = NULL;
+
+ (void)tile_net_update();
+
+ if (priv->loopify_channel >= 0) {
+ if (gxio_mpipe_link_close(&priv->loopify_link) != 0)
+ pr_warning("Failed to close loopify link!\n");
+ priv->loopify_channel = -1;
+ }
+
+ if (priv->channel >= 0) {
+ if (gxio_mpipe_link_close(&priv->link) != 0)
+ pr_warning("Failed to close link!\n");
+ priv->channel = -1;
+ }
+
+ mutex_unlock(&tile_net_devs_mutex);
+
+ return 0;
+}
+
+
+/* Determine the VA for a fragment. */
+static inline void *tile_net_frag_buf(skb_frag_t *f)
+{
+ unsigned long pfn = page_to_pfn(skb_frag_page(f));
+ return pfn_to_kaddr(pfn) + f->page_offset;
+}
+
+
+/* This function takes "skb", consisting of a header template and a
+ * (presumably) huge payload, and egresses it as one or more segments
+ * (aka packets), each consisting of a (possibly modified) copy of the
+ * header plus a piece of the payload, via "tcp segmentation offload".
+ *
+ * Usually, "data" will contain the header template, of size "sh_len",
+ * and "sh->frags" will contain "skb->data_len" bytes of payload, and
+ * there will be "sh->gso_segs" segments.
+ *
+ * Sometimes, if "sendfile()" requires copying, we will be called with
+ * "data" containing the header and payload, with "frags" being empty.
+ *
+ * Sometimes, for example when using NFS over TCP, a single segment can
+ * span 3 fragments. This requires special care below.
+ *
+ * See "emulate_large_send_offload()" for some reference code, which
+ * does not handle checksumming.
+ */
+static int tile_net_tx_tso(struct sk_buff *skb, struct net_device *dev)
+{
+ struct tile_net_priv *priv = netdev_priv(dev);
+
+ gxio_mpipe_equeue_t *equeue = priv->equeue;
+
+ struct tile_net_info_t *info = &__get_cpu_var(per_cpu_info);
+
+ struct tile_net_stats_t *stats;
+
+ unsigned int len = skb->len;
+ unsigned char *data = skb->data;
+
+ /* The ip header follows the ethernet header. */
+ struct iphdr *ih = ip_hdr(skb);
+ unsigned int ih_len = ih->ihl * 4;
+
+ /* Note that "nh == iph", by definition. */
+ unsigned char *nh = skb_network_header(skb);
+ unsigned int eh_len = nh - data;
+
+ /* The tcp header follows the ip header. */
+ struct tcphdr *th = (struct tcphdr *)(nh + ih_len);
+ unsigned int th_len = th->doff * 4;
+
+ /* The total number of header bytes. */
+ unsigned int sh_len = eh_len + ih_len + th_len;
+
+ /* Help compute "jh->check". */
+ unsigned int isum_hack =
+ ((0xFFFF - ih->check) +
+ (0xFFFF - ih->tot_len) +
+ (0xFFFF - ih->id));
+
+ /* Help compute "uh->check". */
+ unsigned int tsum_hack = th->check + (0xFFFF ^ htons(len));
+
+ struct skb_shared_info *sh = skb_shinfo(skb);
+
+ /* The maximum payload size. */
+ unsigned int gso_size = sh->gso_size;
+
+ /* The size of the initial segments (including header). */
+ unsigned int mtu = sh_len + gso_size;
+
+ /* The size of the final segment (including header). */
+ unsigned int mtu2 = len - ((sh->gso_segs - 1) * gso_size);
+
+ /* Track tx stats. */
+ unsigned int tx_packets = 0;
+ unsigned int tx_bytes = 0;
+
+ /* Which segment are we on. */
+ unsigned int segment;
+
+ /* Get the initial ip "id". */
+ u16 id = ntohs(ih->id);
+
+ /* Get the initial tcp "seq". */
+ u32 seq = ntohl(th->seq);
+
+ /* The id of the current fragment (or -1). */
+ long f_id;
+
+ /* The size of the current fragment (or -1). */
+ long f_size;
+
+ /* The bytes used from the current fragment (or -1). */
+ long f_used;
+
+ /* The size of the current piece of payload. */
+ long n;
+
+ /* Prepare checksum info. */
+ unsigned int csum_start = skb_checksum_start_offset(skb);
+
+ /* The header/payload edesc's. */
+ gxio_mpipe_edesc_t edesc_head = { { 0 } };
+ gxio_mpipe_edesc_t edesc_body = { { 0 } };
+
+ /* Total number of edescs needed. */
+ unsigned int num_edescs = 0;
+
+ unsigned long irqflags;
+
+ /* First reserved egress slot. */
+ s64 slot;
+
+ struct tile_net_comps *comps;
+
+ int cid;
+
+ /* Empty packets (etc) would cause trouble below. */
+ BUG_ON(skb->data_len == 0);
+ BUG_ON(sh->nr_frags == 0);
+ BUG_ON(sh->gso_segs == 0);
+
+ /* We assume the frags contain the entire payload. */
+ BUG_ON(skb_headlen(skb) != sh_len);
+ BUG_ON(len != sh_len + skb->data_len);
+
+ /* Implicitly verify "gso_segs" and "gso_size". */
+ BUG_ON(mtu2 > mtu);
+
+ /* We only have HEADER_BYTES for each header. */
+ BUG_ON(NET_IP_ALIGN + sh_len > HEADER_BYTES);
+
+ /* Paranoia. */
+ BUG_ON(skb->protocol != htons(ETH_P_IP));
+ BUG_ON(ih->protocol != IPPROTO_TCP);
+ BUG_ON(skb->ip_summed != CHECKSUM_PARTIAL);
+ BUG_ON(csum_start != eh_len + ih_len);
+
+ /* NOTE: ".hwb = 0", so ".size" is unused.
+ * NOTE: ".stack_idx" determines the TLB.
+ */
+
+ /* Prepare to egress the headers. */
+ edesc_head.csum = 1;
+ edesc_head.csum_start = csum_start;
+ edesc_head.csum_dest = csum_start + skb->csum_offset;
+ edesc_head.xfer_size = sh_len;
+ edesc_head.stack_idx = large_buffer_stack;
+
+ /* Prepare to egress the body. */
+ edesc_body.stack_idx = large_buffer_stack;
+
+ /* Reset. */
+ f_id = f_size = f_used = -1;
+
+ /* Determine how many edesc's are needed. */
+ for (segment = 0; segment < sh->gso_segs; segment++) {
+
+ /* Detect the final segment. */
+ bool final = (segment == sh->gso_segs - 1);
+
+ /* The segment size (including header). */
+ unsigned int s_len = final ? mtu2 : mtu;
+
+ /* The size of the payload. */
+ unsigned int p_len = s_len - sh_len;
+
+ /* The bytes used from the payload. */
+ unsigned int p_used = 0;
+
+ /* One edesc for the header. */
+ num_edescs++;
+
+ /* One edesc for each piece of the payload. */
+ while (p_used < p_len) {
+
+ /* Advance as needed. */
+ while (f_used >= f_size) {
+ f_id++;
+ f_size = sh->frags[f_id].size;
+ f_used = 0;
+ }
+
+ /* Use bytes from the current fragment. */
+ n = p_len - p_used;
+ if (n > f_size - f_used)
+ n = f_size - f_used;
+ f_used += n;
+ p_used += n;
+
+ num_edescs++;
+ }
+ }
+
+ /* Verify all fragments consumed. */
+ BUG_ON(f_id + 1 != sh->nr_frags);
+ BUG_ON(f_used != f_size);
+
+ local_irq_save(irqflags);
+
+ /* Reserve slots, or return NETDEV_TX_BUSY if "full". */
+ slot = gxio_mpipe_equeue_try_reserve(equeue, num_edescs);
+ if (slot < 0) {
+ if (net_ratelimit())
+ pr_info("Egress blocked on '%s'!\n", dev->name);
+ local_irq_restore(irqflags);
+ return NETDEV_TX_BUSY;
+ }
+
+ /* Reset. */
+ f_id = f_size = f_used = -1;
+
+ /* Prepare all the headers. */
+ for (segment = 0; segment < sh->gso_segs; segment++) {
+
+ /* Detect the final segment. */
+ bool final = (segment == sh->gso_segs - 1);
+
+ /* The segment size (including header). */
+ unsigned int s_len = final ? mtu2 : mtu;
+
+ /* The size of the payload. */
+ unsigned int p_len = s_len - sh_len;
+
+ /* The bytes used from the payload. */
+ unsigned int p_used = 0;
+
+ /* Access the header memory for this segment. */
+ unsigned int bn = slot % EQUEUE_ENTRIES;
+ unsigned char *buf =
+ priv->headers + bn * HEADER_BYTES + NET_IP_ALIGN;
+
+ /* The soon-to-be copied "ip" header. */
+ struct iphdr *jh = (struct iphdr *)(buf + eh_len);
+
+ /* The soon-to-be copied "tcp" header. */
+ struct tcphdr *uh = (struct tcphdr *)(buf + eh_len + ih_len);
+
+ unsigned int jsum, usum;
+
+ /* Copy the header. */
+ memcpy(buf, data, sh_len);
+
+ /* The packet size, not including ethernet header. */
+ jh->tot_len = htons(s_len - eh_len);
+
+ /* Update the ip "id". */
+ jh->id = htons(id);
+
+ /* Compute the "ip checksum". */
+ jsum = isum_hack + htons(s_len - eh_len) + htons(id);
+ jsum = __insn_v2sadu(jsum, 0);
+ jsum = __insn_v2sadu(jsum, 0);
+ jsum = (0xFFFF ^ jsum);
+ jh->check = jsum;
+
+ /* Update the tcp "seq". */
+ uh->seq = htonl(seq);
+
+ /* Update some flags. */
+ if (!final)
+ uh->fin = uh->psh = 0;
+
+ /* Compute the tcp pseudo-header checksum. */
+ usum = tsum_hack + htons(s_len);
+ usum = __insn_v2sadu(usum, 0);
+ usum = __insn_v2sadu(usum, 0);
+ uh->check = usum;
+
+ /* Skip past the header. */
+ slot++;
+
+ /* Skip past the payload. */
+ while (p_used < p_len) {
+
+ /* Advance as needed. */
+ while (f_used >= f_size) {
+ f_id++;
+ f_size = sh->frags[f_id].size;
+ f_used = 0;
+ }
+
+ /* Use bytes from the current fragment. */
+ n = p_len - p_used;
+ if (n > f_size - f_used)
+ n = f_size - f_used;
+ f_used += n;
+ p_used += n;
+
+ slot++;
+ }
+
+ id++;
+ seq += p_len;
+ }
+
+ /* Reset "slot". */
+ slot -= num_edescs;
+
+ /* Flush the headers. */
+ __insn_mf();
+
+ /* Reset. */
+ f_id = f_size = f_used = -1;
+
+ /* Egress all the edescs. */
+ for (segment = 0; segment < sh->gso_segs; segment++) {
+
+ /* Detect the final segment. */
+ bool final = (segment == sh->gso_segs - 1);
+
+ /* The segment size (including header). */
+ unsigned int s_len = final ? mtu2 : mtu;
+
+ /* The size of the payload. */
+ unsigned int p_len = s_len - sh_len;
+
+ /* The bytes used from the payload. */
+ unsigned int p_used = 0;
+
+ /* Access the header memory for this segment. */
+ unsigned int bn = slot % EQUEUE_ENTRIES;
+ unsigned char *buf =
+ priv->headers + bn * HEADER_BYTES + NET_IP_ALIGN;
+
+ void *va;
+
+ /* Egress the header. */
+ edesc_head.va = (ulong)buf_to_cpa(buf);
+ gxio_mpipe_equeue_put_at(equeue, edesc_head, slot);
+ slot++;
+
+ /* Egress the payload. */
+ while (p_used < p_len) {
+
+ /* Advance as needed. */
+ while (f_used >= f_size) {
+ f_id++;
+ f_size = sh->frags[f_id].size;
+ f_used = 0;
+ }
+
+ va = tile_net_frag_buf(&sh->frags[f_id]) + f_used;
+
+ /* Use bytes from the current fragment. */
+ n = p_len - p_used;
+ if (n > f_size - f_used)
+ n = f_size - f_used;
+ f_used += n;
+ p_used += n;
+
+ /* Egress a piece of the payload. */
+ edesc_body.va = (ulong)buf_to_cpa(va);
+ edesc_body.xfer_size = n;
+ edesc_body.bound = !(p_used < p_len);
+ gxio_mpipe_equeue_put_at(equeue, edesc_body, slot);
+ slot++;
+ }
+
+ tx_packets++;
+ tx_bytes += s_len;
+ }
+
+ comps = info->comps_for_dev[priv->devno];
+ cid = comps->comp_next % TILE_NET_MAX_COMPS;
+
+ /* Wait for a free completion entry.
+ * ISSUE: Is this the best logic?
+ * ISSUE: Can this cause undesirable "blocking"?
+ */
+ while (comps->comp_next - comps->comp_last >= TILE_NET_MAX_COMPS - 1)
+ tile_net_free_comps(dev, comps, 32, false);
+
+ /* Update the completions array. */
+ comps->comp_queue[cid].when = slot;
+ comps->comp_queue[cid].skb = skb;
+ comps->comp_next++;
+
+ /* Update stats. */
+ stats = &info->stats_for_dev[priv->devno];
+ stats->tx_packets += tx_packets;
+ stats->tx_bytes += tx_bytes;
+
+ local_irq_restore(irqflags);
+
+ /* Make sure the egress timer is scheduled. */
+ tile_net_schedule_egress_timer(info);
+
+ return NETDEV_TX_OK;
+}
+
+
+/* Analyze the body and frags for a transmit request. */
+static unsigned int tile_net_tx_frags(struct frag *frags,
+ struct sk_buff *skb,
+ void *b_data, unsigned int b_len)
+{
+ unsigned int i, n = 0;
+
+ struct skb_shared_info *sh = skb_shinfo(skb);
+
+ if (b_len != 0) {
+ frags[n].buf = b_data;
+ frags[n++].length = b_len;
+ }
+
+ for (i = 0; i < sh->nr_frags; i++) {
+ skb_frag_t *f = &sh->frags[i];
+ frags[n].buf = tile_net_frag_buf(f);
+ frags[n++].length = skb_frag_size(f);
+ }
+
+ return n;
+}
+
+
+/* Help the kernel transmit a packet. */
+static int tile_net_tx(struct sk_buff *skb, struct net_device *dev)
+{
+ struct tile_net_priv *priv = netdev_priv(dev);
+
+ gxio_mpipe_equeue_t *equeue = priv->equeue;
+
+ struct tile_net_info_t *info = &__get_cpu_var(per_cpu_info);
+
+ struct tile_net_stats_t *stats;
+
+ struct skb_shared_info *sh = skb_shinfo(skb);
+
+ unsigned int len = skb->len;
+ unsigned char *data = skb->data;
+
+ unsigned int num_frags;
+ struct frag frags[MAX_FRAGS];
+ gxio_mpipe_edesc_t edescs[MAX_FRAGS];
+
+ struct tile_net_comps *comps;
+
+ unsigned int i;
+
+ int cid;
+
+ s64 slot;
+
+ unsigned long irqflags;
+
+ /* Save the timestamp. */
+ dev->trans_start = jiffies;
+
+#ifdef TILE_NET_DUMP_PACKETS
+ /* ISSUE: Does not dump the "frags". */
+ dump_packet(data, skb_headlen(skb), "tx");
+#endif /* TILE_NET_DUMP_PACKETS */
+
+ if (sh->gso_size != 0)
+ return tile_net_tx_tso(skb, dev);
+
+ /* NOTE: This is usually 2, sometimes 3, for big writes. */
+ num_frags = tile_net_tx_frags(frags, skb, data, skb_headlen(skb));
+
+ /* Prepare the edescs. */
+ for (i = 0; i < num_frags; i++) {
+
+ /* NOTE: ".hwb = 0", so ".size" is unused.
+ * NOTE: ".stack_idx" determines the TLB.
+ */
+
+ gxio_mpipe_edesc_t edesc = { { 0 } };
+
+ /* Prepare the basic command. */
+ edesc.bound = (i == num_frags - 1);
+ edesc.xfer_size = frags[i].length;
+ edesc.va = (ulong)buf_to_cpa(frags[i].buf);
+ edesc.stack_idx = large_buffer_stack;
+
+ edescs[i] = edesc;
+ }
+
+ /* Add checksum info if needed. */
+ if (skb->ip_summed == CHECKSUM_PARTIAL) {
+ unsigned int csum_start = skb->csum_start - skb_headroom(skb);
+ edescs[0].csum = 1;
+ edescs[0].csum_start = csum_start;
+ edescs[0].csum_dest = csum_start + skb->csum_offset;
+ }
+
+ local_irq_save(irqflags);
+
+ /* Reserve slots, or return NETDEV_TX_BUSY if "full". */
+ slot = gxio_mpipe_equeue_try_reserve(equeue, num_frags);
+ if (slot < 0) {
+ if (net_ratelimit())
+ pr_info("Egress blocked on '%s'!\n", dev->name);
+ local_irq_restore(irqflags);
+ return NETDEV_TX_BUSY;
+ }
+
+ for (i = 0; i < num_frags; i++)
+ gxio_mpipe_equeue_put_at(equeue, edescs[i], slot + i);
+
+ comps = info->comps_for_dev[priv->devno];
+ cid = comps->comp_next % TILE_NET_MAX_COMPS;
+
+ /* Wait for a free completion entry.
+ * ISSUE: Is this the best logic?
+ */
+ while (comps->comp_next - comps->comp_last >= TILE_NET_MAX_COMPS - 1)
+ tile_net_free_comps(dev, comps, 32, false);
+
+ /* Update the completions array. */
+ comps->comp_queue[cid].when = slot + num_frags;
+ comps->comp_queue[cid].skb = skb;
+ comps->comp_next++;
+
+ /* HACK: Track "expanded" size for short packets (e.g. 42 < 60). */
+ stats = &info->stats_for_dev[priv->devno];
+ stats->tx_packets++;
+ stats->tx_bytes += ((len >= ETH_ZLEN) ? len : ETH_ZLEN);
+
+ local_irq_restore(irqflags);
+
+ /* Make sure the egress timer is scheduled. */
+ tile_net_schedule_egress_timer(info);
+
+ return NETDEV_TX_OK;
+}
+
+
+/* Deal with a transmit timeout. */
+static void tile_net_tx_timeout(struct net_device *dev)
+{
+ /* ISSUE: This doesn't seem useful for us. */
+ netif_wake_queue(dev);
+}
+
+
+/* Ioctl commands. */
+static int tile_net_ioctl(struct net_device *dev, struct ifreq *rq, int cmd)
+{
+ return -EOPNOTSUPP;
+}
+
+
+/* Get System Network Statistics.
+ *
+ * Returns the address of the device statistics structure.
+ */
+static struct net_device_stats *tile_net_get_stats(struct net_device *dev)
+{
+ struct tile_net_priv *priv = netdev_priv(dev);
+
+ int devno = priv->devno;
+
+ u32 rx_packets = 0;
+ u32 tx_packets = 0;
+ u32 rx_bytes = 0;
+ u32 tx_bytes = 0;
+ int i;
+
+ for_each_online_cpu(i) {
+ rx_packets += infos[i]->stats_for_dev[devno].rx_packets;
+ rx_bytes += infos[i]->stats_for_dev[devno].rx_bytes;
+ tx_packets += infos[i]->stats_for_dev[devno].tx_packets;
+ tx_bytes += infos[i]->stats_for_dev[devno].tx_bytes;
+ }
+
+ priv->stats.rx_packets = rx_packets;
+ priv->stats.rx_bytes = rx_bytes;
+ priv->stats.tx_packets = tx_packets;
+ priv->stats.tx_bytes = tx_bytes;
+
+ return &priv->stats;
+}
+
+
+/* Change the "mtu". */
+static int tile_net_change_mtu(struct net_device *dev, int new_mtu)
+{
+ /* Check ranges. */
+ if ((new_mtu < 68) || (new_mtu > 1500))
+ return -EINVAL;
+
+ /* Accept the value. */
+ dev->mtu = new_mtu;
+
+ return 0;
+}
+
+
+/* Change the Ethernet Address of the NIC.
+ *
+ * The hypervisor driver does not support changing MAC address. However,
+ * the hardware does not do anything with the MAC address, so the address
+ * which gets used on outgoing packets, and which is accepted on incoming
+ * packets, is completely up to us.
+ *
+ * Returns 0 on success, negative on failure.
+ */
+static int tile_net_set_mac_address(struct net_device *dev, void *p)
+{
+ struct sockaddr *addr = p;
+
+ if (!is_valid_ether_addr(addr->sa_data))
+ return -EINVAL;
+
+ memcpy(dev->dev_addr, addr->sa_data, dev->addr_len);
+
+ return 0;
+}
+
+
+#ifdef CONFIG_NET_POLL_CONTROLLER
+/* Polling 'interrupt' - used by things like netconsole to send skbs
+ * without having to re-enable interrupts. It's not called while
+ * the interrupt routine is executing.
+ */
+static void tile_net_netpoll(struct net_device *dev)
+{
+ disable_percpu_irq(ingress_irq);
+ tile_net_handle_ingress_irq(ingress_irq, NULL);
+ enable_percpu_irq(ingress_irq, 0);
+}
+#endif
+
+
+static const struct net_device_ops tile_net_ops = {
+ .ndo_open = tile_net_open,
+ .ndo_stop = tile_net_stop,
+ .ndo_start_xmit = tile_net_tx,
+ .ndo_do_ioctl = tile_net_ioctl,
+ .ndo_get_stats = tile_net_get_stats,
+ .ndo_change_mtu = tile_net_change_mtu,
+ .ndo_tx_timeout = tile_net_tx_timeout,
+ .ndo_set_mac_address = tile_net_set_mac_address,
+#ifdef CONFIG_NET_POLL_CONTROLLER
+ .ndo_poll_controller = tile_net_netpoll,
+#endif
+};
+
+/* The setup function.
+ *
+ * This uses ether_setup() to assign various fields in dev, including
+ * setting IFF_BROADCAST and IFF_MULTICAST, then sets some extra fields.
+ */
+static void tile_net_setup(struct net_device *dev)
+{
+ ether_setup(dev);
+
+ dev->netdev_ops = &tile_net_ops;
+ dev->watchdog_timeo = TILE_NET_TIMEOUT;
+
+ /* We want lockless xmit. */
+ dev->features |= NETIF_F_LLTX;
+
+ /* We support hardware tx checksums. */
+ dev->features |= NETIF_F_HW_CSUM;
+
+ /* We support scatter/gather. */
+ dev->features |= NETIF_F_SG;
+
+#ifdef TILE_NET_GSO
+ /* We support GSO. */
+ dev->features |= NETIF_F_GSO;
+#endif
+
+#ifdef TILE_NET_TSO
+ /* We support TSO. */
+ dev->features |= NETIF_F_TSO;
+#endif
+
+ dev->tx_queue_len = TILE_NET_TX_QUEUE_LEN;
+
+ dev->mtu = 1500;
+}
+
+
+/* Allocate the device structure, register the device, and obtain the
+ * MAC address from the hypervisor.
+ */
+static void tile_net_dev_init(const char *name, const uint8_t* mac)
+{
+ int ret;
+ int devno = 0;
+ int i;
+ int nz_addr = 0;
+ struct net_device *dev;
+ struct tile_net_priv *priv;
+
+ /* HACK: Ignore "loop" links. */
+ if (strncmp(name, "loop", 4) == 0)
+ return;
+
+ /* Find the next available devno. */
+ while (tile_net_devs[devno] != NULL)
+ devno++;
+
+ /* Allocate the device structure. This allocates "priv", calls
+ * tile_net_setup(), and saves "name". Normally, "name" is a
+ * template, instantiated by register_netdev(), but not for us.
+ */
+ dev = alloc_netdev(sizeof(*priv), name, tile_net_setup);
+ if (!dev) {
+ pr_err("alloc_netdev(%s) failed\n", name);
+ return;
+ }
+
+ priv = netdev_priv(dev);
+
+ /* Initialize "priv". */
+
+ memset(priv, 0, sizeof(*priv));
+
+ priv->dev = dev;
+ priv->devno = devno;
+
+ priv->channel = priv->loopify_channel = -1;
+
+ /* Save the device. */
+ tile_net_devs[devno] = dev;
+
+ /* Register the network device. */
+ ret = register_netdev(dev);
+ if (ret) {
+ netdev_err(dev, "register_netdev failed %d\n", ret);
+ free_netdev(dev);
+ tile_net_devs[devno] = NULL;
+ return;
+ }
+
+ /* Get the MAC address and set it in the device struct; this must
+ * be done before the device is opened. If the MAC is all zeroes,
+ * we use a random address, since we're probably on the simulator.
+ */
+ for (i = 0; i < 6; i++)
+ nz_addr |= mac[i];
+
+ if (nz_addr) {
+ memcpy(dev->dev_addr, mac, 6);
+ dev->addr_len = 6;
+ } else {
+ random_ether_addr(dev->dev_addr);
+ }
+}
+
+
+/* Module cleanup. */
+static void __exit tile_net_cleanup(void)
+{
+ int i;
+
+ for (i = 0; i < TILE_NET_DEVS; i++) {
+ struct net_device *dev = tile_net_devs[i];
+ if (dev != NULL) {
+ unregister_netdev(dev);
+ free_netdev(dev);
+ }
+ }
+}
+
+
+/* Module initialization. */
+static int __init tile_net_init_module(void)
+{
+ int i;
+ char name[GXIO_MPIPE_LINK_NAME_LEN];
+ uint8_t mac[6];
+
+ pr_info("Tilera Network Driver\n");
+
+ mutex_init(&tile_net_devs_mutex);
+
+ /* Initialize each CPU. */
+ on_each_cpu(tile_net_prepare_cpu, NULL, 1);
+
+ /* Find out what devices we have, and initialize them. */
+ for (i = 0; gxio_mpipe_link_enumerate_mac(i, name, mac) >= 0; i++)
+ tile_net_dev_init(name, mac);
+
+ return 0;
+}
+
+
+#ifndef MODULE
+/* The "network_cpus" boot argument specifies the cpus that are dedicated
+ * to handle ingress packets.
+ *
+ * The parameter should be in the form "network_cpus=m-n[,x-y]", where
+ * m, n, x, y are integer numbers that represent the cpus that can be
+ * neither a dedicated cpu nor a dataplane cpu.
+ */
+static int __init network_cpus_setup(char *str)
+{
+ int rc = cpulist_parse_crop(str, &network_cpus_map);
+ if (rc != 0) {
+ pr_warning("network_cpus=%s: malformed cpu list\n",
+ str);
+ } else {
+
+ /* Remove dedicated cpus. */
+ cpumask_and(&network_cpus_map, &network_cpus_map,
+ cpu_possible_mask);
+
+#ifdef CONFIG_DATAPLANE
+ /* Remove dataplane cpus. */
+ cpumask_andnot(&network_cpus_map, &network_cpus_map,
+ &dataplane_map);
+#endif
+
+ if (cpumask_empty(&network_cpus_map)) {
+ pr_warning("Ignoring network_cpus='%s'.\n", str);
+ } else {
+ char buf[1024];
+ cpulist_scnprintf(buf, sizeof(buf), &network_cpus_map);
+ pr_info("Linux network CPUs: %s\n", buf);
+ network_cpus_used = true;
+ }
+ }
+
+ return 0;
+}
+__setup("network_cpus=", network_cpus_setup);
+
+
+/* The "loopify=LINK" boot argument causes the named device to
+ * actually use "loop0" for ingress, and "loop1" for egress. This
+ * allows an app to sit between the actual link and linux, passing
+ * (some) packets along to linux, and forwarding (some) packets sent
+ * out by linux.
+ */
+static int __init loopify_setup(char *str)
+{
+ strncpy(loopify_link_name, str, sizeof(loopify_link_name) - 1);
+ return 0;
+}
+__setup("loopify=", loopify_setup);
+
+#endif
+
+
+module_init(tile_net_init_module);
+module_exit(tile_net_cleanup);
--
1.6.5.2
^ permalink raw reply related
* [PATCH v2 6/6] tilegx network driver: initial support
From: Chris Metcalf @ 2012-04-06 20:42 UTC (permalink / raw)
To: Arnd Bergmann, linux-kernel, netdev
In-Reply-To: <201204291856.q3TIusXq007168@farm-0027.internal.tilera.com>
This change adds support for the tilegx network driver based on the
GXIO IORPC support in the tilegx software stack, using the on-chip
mPIPE packet processing engine.
Signed-off-by: Chris Metcalf <cmetcalf@tilera.com>
---
drivers/net/ethernet/tile/Kconfig | 1 +
drivers/net/ethernet/tile/Makefile | 4 +-
drivers/net/ethernet/tile/tilegx.c | 1952 ++++++++++++++++++++++++++++++++++++
3 files changed, 1955 insertions(+), 2 deletions(-)
create mode 100644 drivers/net/ethernet/tile/tilegx.c
diff --git a/drivers/net/ethernet/tile/Kconfig b/drivers/net/ethernet/tile/Kconfig
index 2d9218f..9184b61 100644
--- a/drivers/net/ethernet/tile/Kconfig
+++ b/drivers/net/ethernet/tile/Kconfig
@@ -7,6 +7,7 @@ config TILE_NET
depends on TILE
default y
select CRC32
+ select TILE_GXIO_MPIPE if TILEGX
---help---
This is a standard Linux network device driver for the
on-chip Tilera Gigabit Ethernet and XAUI interfaces.
diff --git a/drivers/net/ethernet/tile/Makefile b/drivers/net/ethernet/tile/Makefile
index f634f14..0ef9eef 100644
--- a/drivers/net/ethernet/tile/Makefile
+++ b/drivers/net/ethernet/tile/Makefile
@@ -4,7 +4,7 @@
obj-$(CONFIG_TILE_NET) += tile_net.o
ifdef CONFIG_TILEGX
-tile_net-objs := tilegx.o mpipe.o iorpc_mpipe.o dma_queue.o
+tile_net-y := tilegx.o
else
-tile_net-objs := tilepro.o
+tile_net-y := tilepro.o
endif
diff --git a/drivers/net/ethernet/tile/tilegx.c b/drivers/net/ethernet/tile/tilegx.c
new file mode 100644
index 0000000..169b16c
--- /dev/null
+++ b/drivers/net/ethernet/tile/tilegx.c
@@ -0,0 +1,1952 @@
+/*
+ * Copyright 2012 Tilera Corporation. All Rights Reserved.
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public License
+ * as published by the Free Software Foundation, version 2.
+ *
+ * This program is distributed in the hope that it will be useful, but
+ * WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY OR FITNESS FOR A PARTICULAR PURPOSE, GOOD TITLE or
+ * NON INFRINGEMENT. See the GNU General Public License for
+ * more details.
+ */
+
+#include <linux/module.h>
+#include <linux/init.h>
+#include <linux/moduleparam.h>
+#include <linux/sched.h>
+#include <linux/kernel.h> /* printk() */
+#include <linux/slab.h> /* kmalloc() */
+#include <linux/errno.h> /* error codes */
+#include <linux/types.h> /* size_t */
+#include <linux/interrupt.h>
+#include <linux/in.h>
+#include <linux/irq.h>
+#include <linux/netdevice.h> /* struct device, and other headers */
+#include <linux/etherdevice.h> /* eth_type_trans */
+#include <linux/skbuff.h>
+#include <linux/ioctl.h>
+#include <linux/cdev.h>
+#include <linux/hugetlb.h>
+#include <linux/in6.h>
+#include <linux/timer.h>
+#include <linux/io.h>
+#include <linux/ctype.h>
+#include <asm/checksum.h>
+#include <asm/homecache.h>
+
+#include <gxio/mpipe.h>
+
+/* For TSO */
+#include <linux/ip.h>
+#include <linux/tcp.h>
+
+
+#include <arch/sim.h>
+
+
+/* #define USE_SIM_PRINTF */
+
+#ifdef USE_SIM_PRINTF
+
+static __attribute__((unused, format (printf, 1, 2))) void
+sim_printf(const char *format, ...)
+{
+ char *str;
+ char buf[1024];
+
+ va_list args;
+ va_start(args, format);
+ (void)vsnprintf(buf, sizeof(buf), format, args);
+ va_end(args);
+
+ /* NOTE: Copied from "sim_print()". */
+ for (str = buf; *str != '\0'; str++) {
+ __insn_mtspr(SPR_SIM_CONTROL, SIM_CONTROL_PUTC |
+ (*str << _SIM_CONTROL_OPERATOR_BITS));
+ }
+ __insn_mtspr(SPR_SIM_CONTROL, SIM_CONTROL_PUTC |
+ (SIM_PUTC_FLUSH_BINARY << _SIM_CONTROL_OPERATOR_BITS));
+}
+
+
+/* HACK: Allow use of "sim_printf()" instead of "printk()". */
+#define printk sim_printf
+
+#endif
+
+
+/* First, "tile_net_init_module()" initializes each network cpu to
+ * handle incoming packets, and initializes all the network devices.
+ *
+ * Then, "ifconfig DEVICE up" calls "tile_net_open()", which will
+ * turn on packet processing, if needed.
+ *
+ * If "ifconfig DEVICE down" is called, it uses "tile_net_stop()" to
+ * stop egress, and possibly turn off packet processing.
+ *
+ * We start out with the ingress IRQ enabled on each CPU. When it
+ * fires, it is automatically disabled, and we call "napi_schedule()".
+ * This will cause "tile_net_poll()" to be called, which will pull
+ * packets from the netio queue, filtering them out, or passing them
+ * to "netif_receive_skb()". If our budget is exhausted, we will
+ * return, knowing we will be called again later. Otherwise, we
+ * reenable the ingress IRQ, and call "napi_complete()".
+ *
+ *
+ * NOTE: Failing to free completions for an arbitrarily long time
+ * (which is defined to be illegal) does in fact cause bizarre problems.
+ *
+ * NOTE: The egress code can be interrupted by the interrupt handler.
+ */
+
+
+/* HACK: Define to support GSO.
+ * ISSUE: This may actually hurt performance of the TCP blaster.
+ */
+#undef TILE_NET_GSO
+
+/* HACK: Define to support TSO. */
+#define TILE_NET_TSO
+
+/* Use 3000 to enable the Linux Traffic Control (QoS) layer, else 0. */
+#define TILE_NET_TX_QUEUE_LEN 0
+
+/* Define to dump packets (prints out the whole packet on tx and rx). */
+#undef TILE_NET_DUMP_PACKETS
+
+/* Define to use "round robin" distribution. */
+#undef TILE_NET_ROUND_ROBIN
+
+/* Default transmit lockup timeout period, in jiffies. */
+#define TILE_NET_TIMEOUT (5 * HZ)
+
+/* The maximum number of distinct channels (idesc.channel is 5 bits). */
+#define TILE_NET_CHANNELS 32
+
+/* Maximum number of idescs to handle per "poll". */
+#define TILE_NET_BATCH 128
+
+/* Maximum number of packets to handle per "poll". */
+#define TILE_NET_WEIGHT 64
+
+/* Number of entries in each iqueue. */
+#define IQUEUE_ENTRIES 512
+
+/* Number of entries in each equeue. */
+#define EQUEUE_ENTRIES 2048
+
+/* Total header bytes per equeue slot. Must be big enough for 2 bytes
+ * of NET_IP_ALIGN alignment, plus 14 bytes (?) of L2 header, plus up to
+ * 60 bytes of actual TCP header. We round up to align to cache lines.
+ */
+#define HEADER_BYTES 128
+
+/* Maximum completions per cpu per device (must be a power of two).
+ * ISSUE: What is the right number here?
+ */
+#define TILE_NET_MAX_COMPS 64
+
+
+#define ROUND_UP(n, align) (((n) + (align) - 1) & -(align))
+
+
+#define MAX_FRAGS (65536 / PAGE_SIZE + 2 + 1)
+
+
+MODULE_AUTHOR("Tilera Corporation");
+MODULE_LICENSE("GPL");
+
+
+
+/* A "packet fragment" (a chunk of memory). */
+struct frag {
+ void *buf;
+ size_t length;
+};
+
+
+/* A single completion. */
+struct tile_net_comp {
+ /* The "complete_count" when the completion will be complete. */
+ s64 when;
+ /* The buffer to be freed when the completion is complete. */
+ struct sk_buff *skb;
+};
+
+
+/* The completions for a given cpu and device. */
+struct tile_net_comps {
+ /* The completions. */
+ struct tile_net_comp comp_queue[TILE_NET_MAX_COMPS];
+ /* The number of completions used. */
+ unsigned long comp_next;
+ /* The number of completions freed. */
+ unsigned long comp_last;
+};
+
+
+/* Info for a specific cpu. */
+struct tile_net_info {
+ /* The NAPI struct. */
+ struct napi_struct napi;
+ /* Packet queue. */
+ gxio_mpipe_iqueue_t iqueue;
+ /* Our cpu. */
+ int my_cpu;
+ /* True if iqueue is valid. */
+ bool has_iqueue;
+ /* NAPI flags. */
+ bool napi_added;
+ bool napi_enabled;
+ /* Number of small sk_buffs which must still be provided. */
+ unsigned int num_needed_small_buffers;
+ /* Number of large sk_buffs which must still be provided. */
+ unsigned int num_needed_large_buffers;
+ /* A timer for handling egress completions. */
+ struct timer_list egress_timer;
+ /* True if "egress_timer" is scheduled. */
+ bool egress_timer_scheduled;
+ /* Comps for each egress channel. */
+ struct tile_net_comps *comps_for_echannel[TILE_NET_CHANNELS];
+};
+
+
+/* Info for egress on a particular egress channel. */
+struct tile_net_egress {
+ /* The "equeue". */
+ gxio_mpipe_equeue_t *equeue;
+ /* The headers for TSO. */
+ unsigned char *headers;
+};
+
+
+/* Info for a specific device. */
+struct tile_net_priv {
+ /* Our network device. */
+ struct net_device *dev;
+ /* The primary link. */
+ gxio_mpipe_link_t link;
+ /* The primary channel, if open, else -1. */
+ int channel;
+ /* The "loopify" egress link, if needed. */
+ gxio_mpipe_link_t loopify_link;
+ /* The "loopify" egress channel, if open, else -1. */
+ int loopify_channel;
+ /* The egress channel (channel or loopify_channel). */
+ int echannel;
+ /* Total stats. */
+ struct net_device_stats stats;
+};
+
+
+/* Egress info, indexed by "priv->echannel" (lazily created as needed). */
+static struct tile_net_egress egress_for_echannel[TILE_NET_CHANNELS];
+
+/* Devices currently associated with each channel.
+ * NOTE: The array entry can become NULL after ifconfig down, but
+ * we do not free the underlying net_device structures, so it is
+ * safe to use a pointer after reading it from this array.
+ */
+static struct net_device *tile_net_devs_for_channel[TILE_NET_CHANNELS];
+
+/* A mutex for "tile_net_devs_for_channel". */
+static struct mutex tile_net_devs_for_channel_mutex;
+
+/* The per-cpu info. */
+static DEFINE_PER_CPU(struct tile_net_info, per_cpu_info);
+
+/* Access to "per_cpu_info". */
+static struct tile_net_info *infos[NR_CPUS];
+
+/* The "context" for all devices. */
+static gxio_mpipe_context_t context;
+
+/* The small/large "buffer stacks". */
+static int small_buffer_stack = -1;
+static int large_buffer_stack = -1;
+
+/* The buckets. */
+static int first_bucket = -1;
+static int num_buckets = 1;
+
+/* The ingress irq. */
+static int ingress_irq = -1;
+
+
+/* True if "network_cpus" was specified. */
+static bool network_cpus_used;
+
+/* The actual cpus in "network_cpus". */
+static struct cpumask network_cpus_map;
+
+
+/* If "loopify=LINK" was specified, this is "LINK". */
+static char loopify_link_name[16];
+
+
+/* The "network_cpus" boot argument specifies the cpus that are dedicated
+ * to handle ingress packets.
+ *
+ * The parameter should be in the form "network_cpus=m-n[,x-y]", where
+ * m, n, x, y are integer numbers that represent the cpus that can be
+ * neither a dedicated cpu nor a dataplane cpu.
+ */
+static int __init network_cpus_setup(char *str)
+{
+ int rc = cpulist_parse_crop(str, &network_cpus_map);
+ if (rc != 0) {
+ pr_warning("network_cpus=%s: malformed cpu list\n",
+ str);
+ } else {
+
+ /* Remove dedicated cpus. */
+ cpumask_and(&network_cpus_map, &network_cpus_map,
+ cpu_possible_mask);
+
+
+ if (cpumask_empty(&network_cpus_map)) {
+ pr_warning("Ignoring network_cpus='%s'.\n", str);
+ } else {
+ char buf[1024];
+ cpulist_scnprintf(buf, sizeof(buf), &network_cpus_map);
+ pr_info("Linux network CPUs: %s\n", buf);
+ network_cpus_used = true;
+ }
+ }
+
+ return 0;
+}
+__setup("network_cpus=", network_cpus_setup);
+
+
+/* The "loopify=LINK" boot argument causes the named device to
+ * actually use "loop0" for ingress, and "loop1" for egress. This
+ * allows an app to sit between the actual link and linux, passing
+ * (some) packets along to linux, and forwarding (some) packets sent
+ * out by linux.
+ */
+static int __init loopify_setup(char *str)
+{
+ strncpy(loopify_link_name, str, sizeof(loopify_link_name) - 1);
+ return 0;
+}
+__setup("loopify=", loopify_setup);
+
+
+#ifdef TILE_NET_DUMP_PACKETS
+/* Dump a packet. */
+static void dump_packet(unsigned char *data, unsigned long length, char *s)
+{
+ unsigned long i;
+ static unsigned int count;
+ char buf[128];
+
+ pr_info("Dumping %s packet of 0x%lx bytes at %p [%d]\n",
+ s, length, data, count++);
+
+ pr_info("\n");
+
+ for (i = 0; i < length; i++) {
+ if ((i & 0xf) == 0)
+ sprintf(buf, "%8.8lx:", i);
+ sprintf(buf + strlen(buf), " %02x", data[i]);
+ if ((i & 0xf) == 0xf || i == length - 1)
+ pr_info("%s\n", buf);
+ }
+
+ pr_info("\n");
+}
+#endif
+
+
+/* Allocate and push a buffer. */
+static bool tile_net_provide_buffer(bool small)
+{
+ int stack = small ? small_buffer_stack : large_buffer_stack;
+
+ /* Buffers must be aligned. */
+ const unsigned long align = 128;
+
+ /* Note that "dev_alloc_skb()" adds NET_SKB_PAD more bytes,
+ * and also "reserves" that many bytes.
+ */
+ int len = sizeof(struct sk_buff **) + align + (small ? 128 : 1664);
+
+ /* Allocate (or fail). */
+ struct sk_buff *skb = dev_alloc_skb(len);
+ if (skb == NULL)
+ return false;
+
+ /* Make room for a back-pointer to 'skb'. */
+ skb_reserve(skb, sizeof(struct sk_buff **));
+
+ /* Make sure we are aligned. */
+ skb_reserve(skb, -(long)skb->data & (align - 1));
+
+ /* Save a back-pointer to 'skb'. */
+ *(struct sk_buff **)(skb->data - sizeof(struct sk_buff **)) = skb;
+
+ /* Make sure "skb" and the back-pointer have been flushed. */
+ wmb();
+
+ gxio_mpipe_push_buffer(&context, stack,
+ (void *)va_to_tile_io_addr(skb->data));
+
+ return true;
+}
+
+
+/* Provide linux buffers to mPIPE. */
+static void tile_net_provide_needed_buffers(struct tile_net_info *info)
+{
+ while (info->num_needed_small_buffers != 0) {
+ if (!tile_net_provide_buffer(true))
+ goto oops;
+ info->num_needed_small_buffers--;
+ }
+
+ while (info->num_needed_large_buffers != 0) {
+ if (!tile_net_provide_buffer(false))
+ goto oops;
+ info->num_needed_large_buffers--;
+ }
+
+ return;
+
+oops:
+
+ /* Add a description to the page allocation failure dump. */
+ pr_notice("Tile %d still needs some buffers\n", info->my_cpu);
+}
+
+
+/* Handle a packet. Return true if "processed", false if "filtered". */
+static bool tile_net_handle_packet(struct tile_net_info *info,
+ gxio_mpipe_idesc_t *idesc)
+{
+ struct net_device *dev = tile_net_devs_for_channel[idesc->channel];
+
+ void *va;
+
+ uint8_t l2_offset = gxio_mpipe_idesc_get_l2_offset(idesc);
+
+ void *buf;
+ unsigned long len;
+
+ int filter = 0;
+
+ /* Drop packets for which no buffer was available.
+ * NOTE: This happens under heavy load.
+ */
+ if (idesc->be) {
+ gxio_mpipe_iqueue_consume(&info->iqueue, idesc);
+ if (net_ratelimit())
+ pr_info("Dropping packet (insufficient buffers).\n");
+ return false;
+ }
+
+ /* Get the raw buffer VA. */
+ va = tile_io_addr_to_va((unsigned long)gxio_mpipe_idesc_get_va(idesc));
+
+ /* Get the actual packet start/length. */
+ buf = va + l2_offset;
+ len = gxio_mpipe_idesc_get_l2_length(idesc);
+
+ /* Point "va" at the raw buffer. */
+ va -= NET_IP_ALIGN;
+
+#ifdef TILE_NET_DUMP_PACKETS
+ dump_packet(buf, len, "rx");
+#endif /* TILE_NET_DUMP_PACKETS */
+
+ if (dev != NULL) {
+ /* ISSUE: Is this needed? */
+ dev->last_rx = jiffies;
+ }
+
+ if (dev == NULL || !(dev->flags & IFF_UP)) {
+ /* Filter packets received before we're up. */
+ filter = 1;
+ } else if (!(dev->flags & IFF_PROMISC)) {
+ /* ISSUE: "eth_type_trans()" implies that "IFF_PROMISC"
+ * is set for "all silly devices", however, it appears
+ * to NOT be set for us, so this code here DOES run.
+ * FIXME: The classifier will soon detect "multicast".
+ */
+ if (!is_multicast_ether_addr(buf)) {
+ /* Filter packets not for our address. */
+ const u8 *mine = dev->dev_addr;
+ filter = compare_ether_addr(mine, buf);
+ }
+ }
+
+ if (filter) {
+
+ /* ISSUE: Update "drop" statistics? */
+
+ gxio_mpipe_iqueue_drop(&info->iqueue, idesc);
+
+ } else {
+
+ struct tile_net_priv *priv = netdev_priv(dev);
+
+ /* Acquire the associated "skb". */
+ struct sk_buff **skb_ptr = va - sizeof(*skb_ptr);
+ struct sk_buff *skb = *skb_ptr;
+
+ /* Paranoia. */
+ if (skb->data != va)
+ panic("Corrupt linux buffer! "
+ "buf=%p, skb=%p, skb->data=%p\n",
+ buf, skb, skb->data);
+
+ /* Skip headroom, and any custom header. */
+ skb_reserve(skb, NET_IP_ALIGN + l2_offset);
+
+ /* Encode the actual packet length. */
+ skb_put(skb, len);
+
+ /* NOTE: This call also sets "skb->dev = dev".
+ * ISSUE: The classifier provides us with "eth_type"
+ * (aka "eth->h_proto"), which is basically the value
+ * returned by "eth_type_trans()".
+ * Note that "eth_type_trans()" computes "skb->pkt_type",
+ * which would be useful for the "filter" check above,
+ * if we had a (modifiable) "skb" to work with.
+ */
+ skb->protocol = eth_type_trans(skb, dev);
+
+ /* Acknowledge "good" hardware checksums. */
+ if (idesc->cs && idesc->csum_seed_val == 0xFFFF)
+ skb->ip_summed = CHECKSUM_UNNECESSARY;
+
+ netif_receive_skb(skb);
+
+ /* Update stats. */
+ atomic_add(1, (atomic_t *)&priv->stats.rx_packets);
+ atomic_add(len, (atomic_t *)&priv->stats.rx_bytes);
+
+ /* Need a new buffer. */
+ if (idesc->size == GXIO_MPIPE_BUFFER_SIZE_128)
+ info->num_needed_small_buffers++;
+ else
+ info->num_needed_large_buffers++;
+ }
+
+ gxio_mpipe_iqueue_consume(&info->iqueue, idesc);
+
+ return !filter;
+}
+
+
+/* Handle some packets for the current CPU.
+ *
+ * This function handles up to TILE_NET_BATCH idescs per call.
+ *
+ * ISSUE: Since we do not provide new buffers until this function is
+ * complete, we must initially provide enough buffers for each network
+ * cpu to fill its iqueue and also its batched idescs.
+ *
+ * ISSUE: The "rotting packet" race condition occurs if a packet
+ * arrives after the queue appears to be empty, and before the
+ * hypervisor interrupt is re-enabled.
+ */
+static int tile_net_poll(struct napi_struct *napi, int budget)
+{
+ struct tile_net_info *info = &__get_cpu_var(per_cpu_info);
+
+ unsigned int work = 0;
+
+ gxio_mpipe_idesc_t *idesc;
+ int i, n;
+
+ /* Process packets. */
+ while ((n = gxio_mpipe_iqueue_try_peek(&info->iqueue, &idesc)) > 0) {
+ for (i = 0; i < n; i++) {
+ if (i == TILE_NET_BATCH)
+ goto done;
+ if (tile_net_handle_packet(info, idesc + i)) {
+ if (++work >= budget)
+ goto done;
+ }
+ }
+ }
+
+ /* There are no packets left. */
+ napi_complete(&info->napi);
+
+ /* Re-enable hypervisor interrupts. */
+ gxio_mpipe_enable_notif_ring_interrupt(&context, info->iqueue.ring);
+
+ /* HACK: Avoid the "rotting packet" problem. */
+ if (gxio_mpipe_iqueue_try_peek(&info->iqueue, &idesc) > 0)
+ napi_schedule(&info->napi);
+
+ /* ISSUE: Handle completions? */
+
+done:
+
+ tile_net_provide_needed_buffers(info);
+
+ return work;
+}
+
+
+/* Handle an ingress interrupt on the current cpu. */
+static irqreturn_t tile_net_handle_ingress_irq(int irq, void *unused)
+{
+ struct tile_net_info *info = &__get_cpu_var(per_cpu_info);
+ napi_schedule(&info->napi);
+ return IRQ_HANDLED;
+}
+
+
+/* Free some completions. This must be called with interrupts blocked. */
+static void tile_net_free_comps(gxio_mpipe_equeue_t* equeue,
+ struct tile_net_comps *comps,
+ int limit, bool force_update)
+{
+ int n = 0;
+ while (comps->comp_last < comps->comp_next) {
+ unsigned int cid = comps->comp_last % TILE_NET_MAX_COMPS;
+ struct tile_net_comp *comp = &comps->comp_queue[cid];
+ if (!gxio_mpipe_equeue_is_complete(equeue, comp->when,
+ force_update || n == 0))
+ return;
+ dev_kfree_skb_irq(comp->skb);
+ comps->comp_last++;
+ if (++n == limit)
+ return;
+ }
+}
+
+
+/* Make sure the egress timer is scheduled.
+ *
+ * Note that we use "schedule if not scheduled" logic instead of the more
+ * obvious "reschedule" logic, because "reschedule" is fairly expensive.
+ */
+static void tile_net_schedule_egress_timer(struct tile_net_info *info)
+{
+ if (!info->egress_timer_scheduled) {
+ mod_timer_pinned(&info->egress_timer, jiffies + 1);
+ info->egress_timer_scheduled = true;
+ }
+}
+
+
+/* The "function" for "info->egress_timer".
+ *
+ * This timer will reschedule itself as long as there are any pending
+ * completions expected for this tile.
+ */
+static void tile_net_handle_egress_timer(unsigned long arg)
+{
+ struct tile_net_info *info = (struct tile_net_info *)arg;
+
+ unsigned int i;
+
+ bool pending = false;
+
+ unsigned long irqflags;
+
+ local_irq_save(irqflags);
+
+ /* The timer is no longer scheduled. */
+ info->egress_timer_scheduled = false;
+
+ /* Free all possible comps for this tile. */
+ for (i = 0; i < TILE_NET_CHANNELS; i++) {
+ struct tile_net_egress *egress = &egress_for_echannel[i];
+ struct tile_net_comps *comps = info->comps_for_echannel[i];
+ if (comps->comp_last >= comps->comp_next)
+ continue;
+ tile_net_free_comps(egress->equeue, comps, -1, true);
+ pending = pending || (comps->comp_last < comps->comp_next);
+ }
+
+ /* Reschedule timer if needed. */
+ if (pending)
+ tile_net_schedule_egress_timer(info);
+
+ local_irq_restore(irqflags);
+}
+
+
+/* Prepare each CPU. */
+static void tile_net_prepare_cpu(void *unused)
+{
+ struct tile_net_info *info = &__get_cpu_var(per_cpu_info);
+
+ int my_cpu = smp_processor_id();
+
+ info->has_iqueue = false;
+
+ info->my_cpu = my_cpu;
+
+ /* Initialize the egress timer. */
+ init_timer(&info->egress_timer);
+ info->egress_timer.data = (long)info;
+ info->egress_timer.function = tile_net_handle_egress_timer;
+
+ infos[my_cpu] = info;
+}
+
+
+/* Helper function for "tile_net_update()". */
+static void tile_net_update_cpu(void *arg)
+{
+ struct net_device *dev = arg;
+
+ struct tile_net_info *info = &__get_cpu_var(per_cpu_info);
+
+ if (info->has_iqueue) {
+ if (dev != NULL) {
+ if (!info->napi_added) {
+ /* FIXME: HACK: We use one of the devices.
+ * ISSUE: We never call "netif_napi_del()".
+ */
+ netif_napi_add(dev, &info->napi,
+ tile_net_poll, TILE_NET_WEIGHT);
+ info->napi_added = true;
+ }
+ if (!info->napi_enabled) {
+ napi_enable(&info->napi);
+ info->napi_enabled = true;
+ }
+ enable_percpu_irq(ingress_irq, 0);
+ } else {
+ disable_percpu_irq(ingress_irq);
+ if (info->napi_enabled) {
+ napi_disable(&info->napi);
+ info->napi_enabled = false;
+ }
+ /* FIXME: Drain the iqueue. */
+ }
+ }
+}
+
+
+/* Helper function for tile_net_open() and tile_net_stop(). */
+static int tile_net_update(void)
+{
+ struct net_device *dev = NULL;
+ int channel;
+ long count = 0;
+ int cpu;
+
+ /* HACK: This is too big for the linux stack. */
+ static gxio_mpipe_rules_t rules;
+
+ gxio_mpipe_rules_init(&rules, &context);
+
+ /* TODO: Add support for "dmac" splitting? */
+ for (channel = 0; channel < TILE_NET_CHANNELS; channel++) {
+ if (tile_net_devs_for_channel[channel] == NULL)
+ continue;
+ if (dev == NULL) {
+ dev = tile_net_devs_for_channel[channel];
+ gxio_mpipe_rules_begin(&rules, first_bucket,
+ num_buckets, NULL);
+ gxio_mpipe_rules_set_headroom(&rules, NET_IP_ALIGN);
+ }
+ gxio_mpipe_rules_add_channel(&rules, channel);
+ }
+
+ /* NOTE: This can happen if there is no classifier.
+ * ISSUE: Can anything else cause it to happen?
+ */
+ if (gxio_mpipe_rules_commit(&rules) != 0) {
+ pr_warning("Failed to update classifier rules!\n");
+ return -EIO;
+ }
+
+ /* Update all cpus, sequentially (to protect "netif_napi_add()"). */
+ for_each_online_cpu(cpu)
+ smp_call_function_single(cpu, tile_net_update_cpu, dev, 1);
+
+ /* HACK: Allow packets to flow. */
+ if (count != 0)
+ sim_enable_mpipe_links(0, -1);
+
+ return 0;
+}
+
+
+/* Helper function for "tile_net_init_cpus()". */
+static void tile_net_init_stacks(int network_cpus_count)
+{
+ int err;
+ int i;
+
+ gxio_mpipe_buffer_size_enum_t small_buf_size =
+ GXIO_MPIPE_BUFFER_SIZE_128;
+ gxio_mpipe_buffer_size_enum_t large_buf_size =
+ GXIO_MPIPE_BUFFER_SIZE_1664;
+
+ int num_buffers;
+
+ size_t stack_bytes;
+
+ pte_t pte = { 0 };
+
+ void *mem;
+
+ num_buffers =
+ network_cpus_count * (IQUEUE_ENTRIES + TILE_NET_BATCH);
+
+ /* Compute stack bytes, honoring the 64KB minimum alignment. */
+ stack_bytes = ROUND_UP(gxio_mpipe_calc_buffer_stack_bytes(num_buffers),
+ 64 * 1024);
+ if (stack_bytes > HPAGE_SIZE)
+ panic("Cannot allocate %d physically contiguous buffers.",
+ num_buffers);
+
+#if 0
+ sim_printf("Using %d buffers for %d network cpus.\n",
+ num_buffers, network_cpus_count);
+#endif
+
+ /* Allocate two buffer stacks. */
+ small_buffer_stack = gxio_mpipe_alloc_buffer_stacks(&context, 2, 0, 0);
+ if (small_buffer_stack < 0)
+ panic("Failure in 'gxio_mpipe_alloc_buffer_stacks()'");
+ large_buffer_stack = small_buffer_stack + 1;
+
+ /* Allocate the small memory stack. */
+ mem = alloc_pages_exact(stack_bytes, GFP_KERNEL);
+ if (mem == NULL)
+ panic("Could not allocate buffer memory!");
+ err = gxio_mpipe_init_buffer_stack(&context, small_buffer_stack,
+ small_buf_size,
+ mem, stack_bytes, 0);
+ if (err != 0)
+ panic("Error %d in 'gxio_mpipe_init_buffer_stack()'.", err);
+
+ /* Allocate the large buffer stack. */
+ mem = alloc_pages_exact(stack_bytes, GFP_KERNEL);
+ if (mem == NULL)
+ panic("Could not allocate buffer memory!");
+ err = gxio_mpipe_init_buffer_stack(&context, large_buffer_stack,
+ large_buf_size,
+ mem, stack_bytes, 0);
+ if (err != 0)
+ panic("Error %d in 'gxio_mpipe_init_buffer_stack()'.", err);
+
+ /* Pin all the client memory. */
+ pte = pte_set_home(pte, PAGE_HOME_HASH);
+ err = gxio_mpipe_register_client_memory(&context, small_buffer_stack,
+ pte, 0);
+ if (err != 0)
+ panic("Error %d in 'gxio_mpipe_register_buffer_memory()'.",
+ err);
+ err = gxio_mpipe_register_client_memory(&context, large_buffer_stack,
+ pte, 0);
+ if (err != 0)
+ panic("Error %d in 'gxio_mpipe_register_buffer_memory()'.",
+ err);
+
+ /* Provide initial buffers. */
+ for (i = 0; i < num_buffers; i++) {
+ if (!tile_net_provide_buffer(true))
+ panic("Cannot provide initial buffers!");
+ }
+ for (i = 0; i < num_buffers; i++) {
+ if (!tile_net_provide_buffer(false))
+ panic("Cannot provide initial buffers!");
+ }
+}
+
+
+/* Actually initialize the mPIPE state. */
+static int tile_net_init_cpus(void)
+{
+ int network_cpus_count;
+
+ int ring;
+ int group;
+
+ int next_ring;
+
+ int cpu;
+
+ int i;
+
+#ifdef TILE_NET_ROUND_ROBIN
+ gxio_mpipe_bucket_mode_t mode = GXIO_MPIPE_BUCKET_ROUND_ROBIN;
+#else
+ /* Use random rebalancing. */
+ gxio_mpipe_bucket_mode_t mode = GXIO_MPIPE_BUCKET_STICKY_FLOW_LOCALITY;
+#endif
+
+ if (!hash_default) {
+ pr_warning("Networking requires hash_default!\n");
+ goto fail;
+ }
+
+ if (gxio_mpipe_init(&context, 0) != 0) {
+ pr_warning("Failed to initialize mPIPE!\n");
+ goto fail;
+ }
+
+ if (!network_cpus_used)
+ network_cpus_map = *cpu_online_mask;
+
+
+ network_cpus_count = cpus_weight(network_cpus_map);
+
+ /* ISSUE: Handle failures more gracefully. */
+ tile_net_init_stacks(network_cpus_count);
+
+ /* Allocate one NotifRing for each network cpu. */
+ ring = gxio_mpipe_alloc_notif_rings(&context, network_cpus_count,
+ 0, 0);
+ if (ring < 0) {
+ pr_warning("Failed to allocate notif rings.\n");
+ goto fail;
+ }
+
+ /* ISSUE: Handle failures below more cleanly. */
+
+ /* Init NotifRings. */
+ next_ring = ring;
+
+ for_each_online_cpu(cpu) {
+
+ size_t notif_ring_size =
+ IQUEUE_ENTRIES * sizeof(gxio_mpipe_idesc_t);
+
+ int order;
+ struct page *page;
+ void *addr;
+
+ struct tile_net_info *info = infos[cpu];
+
+ /* ISSUE: This is overkill. */
+ size_t comps_size =
+ TILE_NET_CHANNELS * sizeof(struct tile_net_comps);
+
+ /* Allocate the "comps". */
+ order = get_order(comps_size);
+ page = homecache_alloc_pages(GFP_KERNEL, order, cpu);
+ if (page == NULL)
+ panic("Failed to allocate comps memory.");
+ addr = pfn_to_kaddr(page_to_pfn(page));
+ /* ISSUE: Is this needed? */
+ memset(addr, 0, comps_size);
+ for (i = 0; i < TILE_NET_CHANNELS; i++)
+ info->comps_for_echannel[i] =
+ addr + i * sizeof(struct tile_net_comps);
+
+ /* Only network cpus can receive packets. */
+ if (!cpu_isset(cpu, network_cpus_map))
+ continue;
+
+ /* Allocate the actual idescs array. */
+ order = get_order(notif_ring_size);
+ page = homecache_alloc_pages(GFP_KERNEL, order, cpu);
+ if (page == NULL)
+ panic("Failed to allocate iqueue memory.");
+ addr = pfn_to_kaddr(page_to_pfn(page));
+
+ if (gxio_mpipe_iqueue_init(&info->iqueue, &context, next_ring,
+ addr, notif_ring_size, 0) != 0)
+ panic("Failure in 'gxio_mpipe_iqueue_init()'.");
+
+ info->has_iqueue = true;
+
+ next_ring++;
+ }
+
+ /* Allocate one NotifGroup. */
+ group = gxio_mpipe_alloc_notif_groups(&context, 1, 0, 0);
+ if (group < 0)
+ panic("Failure in 'gxio_mpipe_alloc_notif_groups()'.");
+
+#ifndef TILE_NET_ROUND_ROBIN
+ if (network_cpus_count > 4)
+ num_buckets = 256;
+ else if (network_cpus_count > 1)
+ num_buckets = 16;
+#endif
+
+ /* Allocate some buckets. */
+ first_bucket = gxio_mpipe_alloc_buckets(&context, num_buckets, 0, 0);
+ if (first_bucket < 0)
+ panic("Failure in 'gxio_mpipe_alloc_buckets()'.");
+
+ /* Init group and buckets. */
+ if (gxio_mpipe_init_notif_group_and_buckets(&context, group, ring,
+ network_cpus_count,
+ first_bucket, num_buckets,
+ mode) != 0)
+ panic("Fail in 'gxio_mpipe_init_notif_group_and_buckets().");
+
+
+ /* Create an irq and register it. */
+ ingress_irq = create_irq();
+ if (ingress_irq < 0)
+ panic("Failed to create irq for ingress.");
+ tile_irq_activate(ingress_irq, TILE_IRQ_PERCPU);
+ BUG_ON(request_irq(ingress_irq, tile_net_handle_ingress_irq,
+ 0, NULL, NULL) != 0);
+
+ for_each_online_cpu(cpu) {
+
+ struct tile_net_info *info = infos[cpu];
+
+ int ring = info->iqueue.ring;
+
+ if (!info->has_iqueue)
+ continue;
+
+ gxio_mpipe_request_notif_ring_interrupt(&context,
+ cpu_x(cpu), cpu_y(cpu),
+ 1, ingress_irq, ring);
+ }
+
+ return 0;
+
+fail:
+ return -EIO;
+}
+
+
+/* Create persistent egress info for a given egress channel.
+ *
+ * Note that this may be shared between, say, "gbe0" and "xgbe0".
+ *
+ * ISSUE: Defer header allocation until TSO is actually needed?
+ */
+static int tile_net_init_egress(int echannel)
+{
+ size_t headers_order;
+ struct page *headers_page;
+ unsigned char* headers;
+
+ size_t edescs_size;
+ int edescs_order;
+ struct page *edescs_page;
+ gxio_mpipe_edesc_t* edescs;
+
+ int equeue_order;
+ struct page *equeue_page;
+ gxio_mpipe_equeue_t* equeue;
+ int edma;
+
+ /* Only initialize once. */
+ if (egress_for_echannel[echannel].equeue != NULL)
+ return 0;
+
+ /* Allocate memory for the "headers". */
+ headers_order = get_order(EQUEUE_ENTRIES * HEADER_BYTES);
+ headers_page = alloc_pages(GFP_KERNEL, headers_order);
+ if (headers_page == NULL) {
+ pr_warning("Could not allocate memory for TSO headers.\n");
+ goto fail;
+ }
+ headers = pfn_to_kaddr(page_to_pfn(headers_page));
+
+ /* Allocate memory for the "edescs". */
+ edescs_size = EQUEUE_ENTRIES * sizeof(*edescs);
+ edescs_order = get_order(edescs_size);
+ edescs_page = alloc_pages(GFP_KERNEL, edescs_order);
+ if (edescs_page == NULL) {
+ pr_warning("Could not allocate memory for eDMA ring.\n");
+ goto fail_headers;
+ }
+ edescs = pfn_to_kaddr(page_to_pfn(edescs_page));
+
+ /* Allocate memory for the "equeue". */
+ equeue_order = get_order(sizeof(*equeue));
+ equeue_page = alloc_pages(GFP_KERNEL, equeue_order);
+ if (equeue_page == NULL) {
+ pr_warning("Could not allocate memory for equeue info.\n");
+ goto fail_edescs;
+ }
+ equeue = pfn_to_kaddr(page_to_pfn(equeue_page));
+
+ /* Allocate an edma ring. */
+ edma = gxio_mpipe_alloc_edma_rings(&context, 1, 0, 0);
+ if (edma < 0) {
+ pr_warning("Could not allocate edma ring.\n");
+ goto fail_equeue;
+ }
+
+ /* Initialize the equeue. This should not fail. */
+ if (gxio_mpipe_equeue_init(equeue, &context, edma, echannel,
+ edescs, edescs_size, 0) != 0)
+ panic("Failure in 'gxio_mpipe_equeue_init()'.");
+
+ /* Done. */
+ egress_for_echannel[echannel].equeue = equeue;
+ egress_for_echannel[echannel].headers = headers;
+ return 0;
+
+fail_equeue:
+ __free_pages(equeue_page, equeue_order);
+
+fail_edescs:
+ __free_pages(edescs_page, edescs_order);
+
+fail_headers:
+ __free_pages(headers_page, headers_order);
+
+fail:
+ return -EIO;
+}
+
+
+/* Help the kernel activate the given network interface. */
+static int tile_net_open(struct net_device *dev)
+{
+ struct tile_net_priv *priv = netdev_priv(dev);
+
+ /* Determine if this is the "loopify" device. */
+ bool loopify = !strcmp(dev->name, loopify_link_name);
+
+ int result;
+
+ mutex_lock(&tile_net_devs_for_channel_mutex);
+
+ if (ingress_irq < 0) {
+ result = tile_net_init_cpus();
+ if (result != 0)
+ goto fail;
+ }
+
+ if (priv->channel < 0) {
+ const char* ln = loopify ? "loop0" : dev->name;
+ if (gxio_mpipe_link_open(&priv->link, &context, ln, 0) < 0) {
+ netdev_err(dev, "Failed to open '%s'.\n", ln);
+ result = -EIO;
+ goto fail;
+ }
+ priv->channel = gxio_mpipe_link_channel(&priv->link);
+ BUG_ON(priv->channel < 0 ||
+ priv->channel >= TILE_NET_CHANNELS);
+ }
+
+ if (loopify && priv->loopify_channel < 0) {
+ if (gxio_mpipe_link_open(&priv->loopify_link,
+ &context, "loop1", 0) < 0) {
+ netdev_err(dev, "Failed to open 'loop1'.\n");
+ result = -EIO;
+ goto fail;
+ }
+ priv->loopify_channel =
+ gxio_mpipe_link_channel(&priv->loopify_link);
+ BUG_ON(priv->loopify_channel < 0 ||
+ priv->loopify_channel >= TILE_NET_CHANNELS);
+ }
+
+ priv->echannel =
+ ((priv->loopify_channel >= 0) ?
+ priv->loopify_channel : priv->channel);
+
+ /* Initialize egress info (if needed). */
+ result = tile_net_init_egress(priv->echannel);
+ if (result != 0)
+ goto fail;
+
+ tile_net_devs_for_channel[priv->channel] = dev;
+
+ result = tile_net_update();
+ if (result != 0)
+ goto fail_channel;
+
+ mutex_unlock(&tile_net_devs_for_channel_mutex);
+
+ /* Start our transmit queue. */
+ netif_start_queue(dev);
+
+ netif_carrier_on(dev);
+
+ return 0;
+
+fail_channel:
+ tile_net_devs_for_channel[priv->channel] = NULL;
+
+fail:
+ if (priv->loopify_channel >= 0) {
+ if (gxio_mpipe_link_close(&priv->loopify_link) != 0)
+ pr_warning("Failed to close loopify link!\n");
+ else
+ priv->loopify_channel = -1;
+ }
+ if (priv->channel >= 0) {
+ if (gxio_mpipe_link_close(&priv->link) != 0)
+ pr_warning("Failed to close link!\n");
+ else
+ priv->channel = -1;
+ }
+
+ priv->echannel = -1;
+
+ mutex_unlock(&tile_net_devs_for_channel_mutex);
+ return result;
+}
+
+
+
+/* Help the kernel deactivate the given network interface. */
+static int tile_net_stop(struct net_device *dev)
+{
+ struct tile_net_priv *priv = netdev_priv(dev);
+
+ /* Stop our transmit queue. */
+ netif_stop_queue(dev);
+
+ mutex_lock(&tile_net_devs_for_channel_mutex);
+
+ tile_net_devs_for_channel[priv->channel] = NULL;
+
+ (void)tile_net_update();
+
+ if (priv->loopify_channel >= 0) {
+ if (gxio_mpipe_link_close(&priv->loopify_link) != 0)
+ pr_warning("Failed to close loopify link!\n");
+ priv->loopify_channel = -1;
+ }
+
+ if (priv->channel >= 0) {
+ if (gxio_mpipe_link_close(&priv->link) != 0)
+ pr_warning("Failed to close link!\n");
+ priv->channel = -1;
+ }
+
+ priv->echannel = -1;
+
+ mutex_unlock(&tile_net_devs_for_channel_mutex);
+
+ return 0;
+}
+
+
+/* Determine the VA for a fragment. */
+static inline void *tile_net_frag_buf(skb_frag_t *f)
+{
+ unsigned long pfn = page_to_pfn(skb_frag_page(f));
+ return pfn_to_kaddr(pfn) + f->page_offset;
+}
+
+
+/* This function takes "skb", consisting of a header template and a
+ * (presumably) huge payload, and egresses it as one or more segments
+ * (aka packets), each consisting of a (possibly modified) copy of the
+ * header plus a piece of the payload, via "tcp segmentation offload".
+ *
+ * Usually, "data" will contain the header template, of size "sh_len",
+ * and "sh->frags" will contain "skb->data_len" bytes of payload, and
+ * there will be "sh->gso_segs" segments.
+ *
+ * Sometimes, if "sendfile()" requires copying, we will be called with
+ * "data" containing the header and payload, with "frags" being empty.
+ *
+ * Sometimes, for example when using NFS over TCP, a single segment can
+ * span 3 fragments. This requires special care below.
+ *
+ * See "emulate_large_send_offload()" for some reference code, which
+ * does not handle checksumming.
+ */
+static int tile_net_tx_tso(struct sk_buff *skb, struct net_device *dev)
+{
+ struct tile_net_priv *priv = netdev_priv(dev);
+
+ struct tile_net_info *info = &__get_cpu_var(per_cpu_info);
+
+ struct tile_net_egress *egress = &egress_for_echannel[priv->echannel];
+ gxio_mpipe_equeue_t *equeue = egress->equeue;
+
+ struct tile_net_comps *comps =
+ info->comps_for_echannel[priv->echannel];
+
+ unsigned int len = skb->len;
+ unsigned char *data = skb->data;
+
+ /* The ip header follows the ethernet header. */
+ struct iphdr *ih = ip_hdr(skb);
+ unsigned int ih_len = ih->ihl * 4;
+
+ /* Note that "nh == iph", by definition. */
+ unsigned char *nh = skb_network_header(skb);
+ unsigned int eh_len = nh - data;
+
+ /* The tcp header follows the ip header. */
+ struct tcphdr *th = (struct tcphdr *)(nh + ih_len);
+ unsigned int th_len = th->doff * 4;
+
+ /* The total number of header bytes. */
+ unsigned int sh_len = eh_len + ih_len + th_len;
+
+ /* Help compute "jh->check". */
+ unsigned int isum_hack =
+ ((0xFFFF - ih->check) +
+ (0xFFFF - ih->tot_len) +
+ (0xFFFF - ih->id));
+
+ /* Help compute "uh->check". */
+ unsigned int tsum_hack = th->check + (0xFFFF ^ htons(len));
+
+ struct skb_shared_info *sh = skb_shinfo(skb);
+
+ /* The maximum payload size. */
+ unsigned int gso_size = sh->gso_size;
+
+ /* The size of the initial segments (including header). */
+ unsigned int mtu = sh_len + gso_size;
+
+ /* The size of the final segment (including header). */
+ unsigned int mtu2 = len - ((sh->gso_segs - 1) * gso_size);
+
+ /* Track tx stats. */
+ unsigned int tx_packets = 0;
+ unsigned int tx_bytes = 0;
+
+ /* Which segment are we on. */
+ unsigned int segment;
+
+ /* Get the initial ip "id". */
+ u16 id = ntohs(ih->id);
+
+ /* Get the initial tcp "seq". */
+ u32 seq = ntohl(th->seq);
+
+ /* The id of the current fragment (or -1). */
+ long f_id;
+
+ /* The size of the current fragment (or -1). */
+ long f_size;
+
+ /* The bytes used from the current fragment (or -1). */
+ long f_used;
+
+ /* The size of the current piece of payload. */
+ long n;
+
+ /* Prepare checksum info. */
+ unsigned int csum_start = skb_checksum_start_offset(skb);
+
+ /* The header/payload edesc's. */
+ gxio_mpipe_edesc_t edesc_head = { { 0 } };
+ gxio_mpipe_edesc_t edesc_body = { { 0 } };
+
+ /* Total number of edescs needed. */
+ unsigned int num_edescs = 0;
+
+ unsigned long irqflags;
+
+ /* First reserved egress slot. */
+ s64 slot;
+
+ int cid;
+
+ /* Empty packets (etc) would cause trouble below. */
+ BUG_ON(skb->data_len == 0);
+ BUG_ON(sh->nr_frags == 0);
+ BUG_ON(sh->gso_segs == 0);
+
+ /* We assume the frags contain the entire payload. */
+ BUG_ON(skb_headlen(skb) != sh_len);
+ BUG_ON(len != sh_len + skb->data_len);
+
+ /* Implicitly verify "gso_segs" and "gso_size". */
+ BUG_ON(mtu2 > mtu);
+
+ /* We only have HEADER_BYTES for each header. */
+ BUG_ON(NET_IP_ALIGN + sh_len > HEADER_BYTES);
+
+ /* Paranoia. */
+ BUG_ON(skb->protocol != htons(ETH_P_IP));
+ BUG_ON(ih->protocol != IPPROTO_TCP);
+ BUG_ON(skb->ip_summed != CHECKSUM_PARTIAL);
+ BUG_ON(csum_start != eh_len + ih_len);
+
+ /* NOTE: ".hwb = 0", so ".size" is unused.
+ * NOTE: ".stack_idx" determines the TLB.
+ */
+
+ /* Prepare to egress the headers. */
+ edesc_head.csum = 1;
+ edesc_head.csum_start = csum_start;
+ edesc_head.csum_dest = csum_start + skb->csum_offset;
+ edesc_head.xfer_size = sh_len;
+ edesc_head.stack_idx = large_buffer_stack;
+
+ /* Prepare to egress the body. */
+ edesc_body.stack_idx = large_buffer_stack;
+
+ /* Reset. */
+ f_id = f_size = f_used = -1;
+
+ /* Determine how many edesc's are needed. */
+ for (segment = 0; segment < sh->gso_segs; segment++) {
+
+ /* Detect the final segment. */
+ bool final = (segment == sh->gso_segs - 1);
+
+ /* The segment size (including header). */
+ unsigned int s_len = final ? mtu2 : mtu;
+
+ /* The size of the payload. */
+ unsigned int p_len = s_len - sh_len;
+
+ /* The bytes used from the payload. */
+ unsigned int p_used = 0;
+
+ /* One edesc for the header. */
+ num_edescs++;
+
+ /* One edesc for each piece of the payload. */
+ while (p_used < p_len) {
+
+ /* Advance as needed. */
+ while (f_used >= f_size) {
+ f_id++;
+ f_size = sh->frags[f_id].size;
+ f_used = 0;
+ }
+
+ /* Use bytes from the current fragment. */
+ n = p_len - p_used;
+ if (n > f_size - f_used)
+ n = f_size - f_used;
+ f_used += n;
+ p_used += n;
+
+ num_edescs++;
+ }
+ }
+
+ /* Verify all fragments consumed. */
+ BUG_ON(f_id + 1 != sh->nr_frags);
+ BUG_ON(f_used != f_size);
+
+ local_irq_save(irqflags);
+
+ /* Reserve slots, or return NETDEV_TX_BUSY if "full". */
+ slot = gxio_mpipe_equeue_try_reserve(equeue, num_edescs);
+ if (slot < 0) {
+ local_irq_restore(irqflags);
+ /* ISSUE: "Virtual device xxx asks to queue packet". */
+ return NETDEV_TX_BUSY;
+ }
+
+ /* Reset. */
+ f_id = f_size = f_used = -1;
+
+ /* Prepare all the headers. */
+ for (segment = 0; segment < sh->gso_segs; segment++) {
+
+ /* Detect the final segment. */
+ bool final = (segment == sh->gso_segs - 1);
+
+ /* The segment size (including header). */
+ unsigned int s_len = final ? mtu2 : mtu;
+
+ /* The size of the payload. */
+ unsigned int p_len = s_len - sh_len;
+
+ /* The bytes used from the payload. */
+ unsigned int p_used = 0;
+
+ /* Access the header memory for this segment. */
+ unsigned int bn = slot % EQUEUE_ENTRIES;
+ unsigned char *buf =
+ egress->headers + bn * HEADER_BYTES + NET_IP_ALIGN;
+
+ /* The soon-to-be copied "ip" header. */
+ struct iphdr *jh = (struct iphdr *)(buf + eh_len);
+
+ /* The soon-to-be copied "tcp" header. */
+ struct tcphdr *uh = (struct tcphdr *)(buf + eh_len + ih_len);
+
+ unsigned int jsum;
+
+ /* Copy the header. */
+ memcpy(buf, data, sh_len);
+
+ /* The packet size, not including ethernet header. */
+ jh->tot_len = htons(s_len - eh_len);
+
+ /* Update the ip "id". */
+ jh->id = htons(id);
+
+ /* Compute the "ip checksum". */
+ jsum = isum_hack + htons(s_len - eh_len) + htons(id);
+ jh->check = csum_long(jsum) ^ 0xffff;
+
+ /* Update the tcp "seq". */
+ uh->seq = htonl(seq);
+
+ /* Update some flags. */
+ if (!final)
+ uh->fin = uh->psh = 0;
+
+ /* Compute the tcp pseudo-header checksum. */
+ uh->check = csum_long(tsum_hack + htons(s_len));
+
+ /* Skip past the header. */
+ slot++;
+
+ /* Skip past the payload. */
+ while (p_used < p_len) {
+
+ /* Advance as needed. */
+ while (f_used >= f_size) {
+ f_id++;
+ f_size = sh->frags[f_id].size;
+ f_used = 0;
+ }
+
+ /* Use bytes from the current fragment. */
+ n = p_len - p_used;
+ if (n > f_size - f_used)
+ n = f_size - f_used;
+ f_used += n;
+ p_used += n;
+
+ slot++;
+ }
+
+ id++;
+ seq += p_len;
+ }
+
+ /* Reset "slot". */
+ slot -= num_edescs;
+
+ /* Flush the headers. */
+ wmb();
+
+ /* Reset. */
+ f_id = f_size = f_used = -1;
+
+ /* Egress all the edescs. */
+ for (segment = 0; segment < sh->gso_segs; segment++) {
+
+ /* Detect the final segment. */
+ bool final = (segment == sh->gso_segs - 1);
+
+ /* The segment size (including header). */
+ unsigned int s_len = final ? mtu2 : mtu;
+
+ /* The size of the payload. */
+ unsigned int p_len = s_len - sh_len;
+
+ /* The bytes used from the payload. */
+ unsigned int p_used = 0;
+
+ /* Access the header memory for this segment. */
+ unsigned int bn = slot % EQUEUE_ENTRIES;
+ unsigned char *buf =
+ egress->headers + bn * HEADER_BYTES + NET_IP_ALIGN;
+
+ void *va;
+
+ /* Egress the header. */
+ edesc_head.va = va_to_tile_io_addr(buf);
+ gxio_mpipe_equeue_put_at(equeue, edesc_head, slot);
+ slot++;
+
+ /* Egress the payload. */
+ while (p_used < p_len) {
+
+ /* Advance as needed. */
+ while (f_used >= f_size) {
+ f_id++;
+ f_size = sh->frags[f_id].size;
+ f_used = 0;
+ }
+
+ va = tile_net_frag_buf(&sh->frags[f_id]) + f_used;
+
+ /* Use bytes from the current fragment. */
+ n = p_len - p_used;
+ if (n > f_size - f_used)
+ n = f_size - f_used;
+ f_used += n;
+ p_used += n;
+
+ /* Egress a piece of the payload. */
+ edesc_body.va = va_to_tile_io_addr(va);
+ edesc_body.xfer_size = n;
+ edesc_body.bound = !(p_used < p_len);
+ gxio_mpipe_equeue_put_at(equeue, edesc_body, slot);
+ slot++;
+ }
+
+ tx_packets++;
+ tx_bytes += s_len;
+ }
+
+ /* Wait for a free completion entry.
+ * ISSUE: Is this the best logic?
+ * ISSUE: Can this cause undesirable "blocking"?
+ */
+ while (comps->comp_next - comps->comp_last >= TILE_NET_MAX_COMPS - 1)
+ tile_net_free_comps(equeue, comps, 32, false);
+
+ /* Update the completions array. */
+ cid = comps->comp_next % TILE_NET_MAX_COMPS;
+ comps->comp_queue[cid].when = slot;
+ comps->comp_queue[cid].skb = skb;
+ comps->comp_next++;
+
+ /* Update stats. */
+ atomic_add(tx_packets, (atomic_t *)&priv->stats.tx_packets);
+ atomic_add(tx_bytes, (atomic_t *)&priv->stats.tx_bytes);
+
+ local_irq_restore(irqflags);
+
+ /* Make sure the egress timer is scheduled. */
+ tile_net_schedule_egress_timer(info);
+
+ return NETDEV_TX_OK;
+}
+
+
+/* Analyze the body and frags for a transmit request. */
+static unsigned int tile_net_tx_frags(struct frag *frags,
+ struct sk_buff *skb,
+ void *b_data, unsigned int b_len)
+{
+ unsigned int i, n = 0;
+
+ struct skb_shared_info *sh = skb_shinfo(skb);
+
+ if (b_len != 0) {
+ frags[n].buf = b_data;
+ frags[n++].length = b_len;
+ }
+
+ for (i = 0; i < sh->nr_frags; i++) {
+ skb_frag_t *f = &sh->frags[i];
+ frags[n].buf = tile_net_frag_buf(f);
+ frags[n++].length = skb_frag_size(f);
+ }
+
+ return n;
+}
+
+
+/* Help the kernel transmit a packet. */
+static int tile_net_tx(struct sk_buff *skb, struct net_device *dev)
+{
+ struct tile_net_priv *priv = netdev_priv(dev);
+
+ struct tile_net_info *info = &__get_cpu_var(per_cpu_info);
+
+ struct tile_net_egress *egress = &egress_for_echannel[priv->echannel];
+ gxio_mpipe_equeue_t *equeue = egress->equeue;
+
+ struct tile_net_comps *comps =
+ info->comps_for_echannel[priv->echannel];
+
+ struct skb_shared_info *sh = skb_shinfo(skb);
+
+ unsigned int len = skb->len;
+ unsigned char *data = skb->data;
+
+ unsigned int num_frags;
+ struct frag frags[MAX_FRAGS];
+ gxio_mpipe_edesc_t edescs[MAX_FRAGS];
+
+ unsigned int i;
+
+ int cid;
+
+ s64 slot;
+
+ unsigned long irqflags;
+
+ /* Save the timestamp. */
+ dev->trans_start = jiffies;
+
+#ifdef TILE_NET_DUMP_PACKETS
+ /* ISSUE: Does not dump the "frags". */
+ dump_packet(data, skb_headlen(skb), "tx");
+#endif /* TILE_NET_DUMP_PACKETS */
+
+ if (sh->gso_size != 0)
+ return tile_net_tx_tso(skb, dev);
+
+ /* NOTE: This is usually 2, sometimes 3, for big writes. */
+ num_frags = tile_net_tx_frags(frags, skb, data, skb_headlen(skb));
+
+ /* Prepare the edescs. */
+ for (i = 0; i < num_frags; i++) {
+
+ /* NOTE: ".hwb = 0", so ".size" is unused.
+ * NOTE: ".stack_idx" determines the TLB.
+ */
+
+ gxio_mpipe_edesc_t edesc = { { 0 } };
+
+ /* Prepare the basic command. */
+ edesc.bound = (i == num_frags - 1);
+ edesc.xfer_size = frags[i].length;
+ edesc.va = va_to_tile_io_addr(frags[i].buf);
+ edesc.stack_idx = large_buffer_stack;
+
+ edescs[i] = edesc;
+ }
+
+ /* Add checksum info if needed. */
+ if (skb->ip_summed == CHECKSUM_PARTIAL) {
+ unsigned int csum_start = skb->csum_start - skb_headroom(skb);
+ edescs[0].csum = 1;
+ edescs[0].csum_start = csum_start;
+ edescs[0].csum_dest = csum_start + skb->csum_offset;
+ }
+
+ local_irq_save(irqflags);
+
+ /* Reserve slots, or return NETDEV_TX_BUSY if "full". */
+ slot = gxio_mpipe_equeue_try_reserve(equeue, num_frags);
+ if (slot < 0) {
+ local_irq_restore(irqflags);
+ /* ISSUE: "Virtual device xxx asks to queue packet". */
+ return NETDEV_TX_BUSY;
+ }
+
+ for (i = 0; i < num_frags; i++)
+ gxio_mpipe_equeue_put_at(equeue, edescs[i], slot + i);
+
+ /* Wait for a free completion entry.
+ * ISSUE: Is this the best logic?
+ * ISSUE: Can this cause undesirable "blocking"?
+ */
+ while (comps->comp_next - comps->comp_last >= TILE_NET_MAX_COMPS - 1)
+ tile_net_free_comps(equeue, comps, 32, false);
+
+ /* Update the completions array. */
+ cid = comps->comp_next % TILE_NET_MAX_COMPS;
+ comps->comp_queue[cid].when = slot + num_frags;
+ comps->comp_queue[cid].skb = skb;
+ comps->comp_next++;
+
+ /* HACK: Track "expanded" size for short packets (e.g. 42 < 60). */
+ atomic_add(1, (atomic_t *)&priv->stats.tx_packets);
+ atomic_add((len >= ETH_ZLEN) ? len : ETH_ZLEN,
+ (atomic_t *)&priv->stats.tx_bytes);
+
+ local_irq_restore(irqflags);
+
+ /* Make sure the egress timer is scheduled. */
+ tile_net_schedule_egress_timer(info);
+
+ return NETDEV_TX_OK;
+}
+
+
+/* Deal with a transmit timeout. */
+static void tile_net_tx_timeout(struct net_device *dev)
+{
+ /* ISSUE: This doesn't seem useful for us. */
+ netif_wake_queue(dev);
+}
+
+
+/* Ioctl commands. */
+static int tile_net_ioctl(struct net_device *dev, struct ifreq *rq, int cmd)
+{
+ return -EOPNOTSUPP;
+}
+
+
+/* Get System Network Statistics.
+ *
+ * Returns the address of the device statistics structure.
+ */
+static struct net_device_stats *tile_net_get_stats(struct net_device *dev)
+{
+ struct tile_net_priv *priv = netdev_priv(dev);
+ return &priv->stats;
+}
+
+
+/* Change the "mtu". */
+static int tile_net_change_mtu(struct net_device *dev, int new_mtu)
+{
+ /* Check ranges. */
+ if ((new_mtu < 68) || (new_mtu > 1500))
+ return -EINVAL;
+
+ /* Accept the value. */
+ dev->mtu = new_mtu;
+
+ return 0;
+}
+
+
+/* Change the Ethernet Address of the NIC.
+ *
+ * The hypervisor driver does not support changing MAC address. However,
+ * the hardware does not do anything with the MAC address, so the address
+ * which gets used on outgoing packets, and which is accepted on incoming
+ * packets, is completely up to us.
+ *
+ * Returns 0 on success, negative on failure.
+ */
+static int tile_net_set_mac_address(struct net_device *dev, void *p)
+{
+ struct sockaddr *addr = p;
+
+ if (!is_valid_ether_addr(addr->sa_data))
+ return -EINVAL;
+
+ memcpy(dev->dev_addr, addr->sa_data, dev->addr_len);
+
+ return 0;
+}
+
+
+#ifdef CONFIG_NET_POLL_CONTROLLER
+/* Polling 'interrupt' - used by things like netconsole to send skbs
+ * without having to re-enable interrupts. It's not called while
+ * the interrupt routine is executing.
+ */
+static void tile_net_netpoll(struct net_device *dev)
+{
+ disable_percpu_irq(ingress_irq);
+ tile_net_handle_ingress_irq(ingress_irq, NULL);
+ enable_percpu_irq(ingress_irq, 0);
+}
+#endif
+
+
+static const struct net_device_ops tile_net_ops = {
+ .ndo_open = tile_net_open,
+ .ndo_stop = tile_net_stop,
+ .ndo_start_xmit = tile_net_tx,
+ .ndo_do_ioctl = tile_net_ioctl,
+ .ndo_get_stats = tile_net_get_stats,
+ .ndo_change_mtu = tile_net_change_mtu,
+ .ndo_tx_timeout = tile_net_tx_timeout,
+ .ndo_set_mac_address = tile_net_set_mac_address,
+#ifdef CONFIG_NET_POLL_CONTROLLER
+ .ndo_poll_controller = tile_net_netpoll,
+#endif
+};
+
+/* The setup function.
+ *
+ * This uses ether_setup() to assign various fields in dev, including
+ * setting IFF_BROADCAST and IFF_MULTICAST, then sets some extra fields.
+ */
+static void tile_net_setup(struct net_device *dev)
+{
+ ether_setup(dev);
+
+ dev->netdev_ops = &tile_net_ops;
+ dev->watchdog_timeo = TILE_NET_TIMEOUT;
+
+ /* We want lockless xmit. */
+ dev->features |= NETIF_F_LLTX;
+
+ /* We support hardware tx checksums. */
+ dev->features |= NETIF_F_HW_CSUM;
+
+ /* We support scatter/gather. */
+ dev->features |= NETIF_F_SG;
+
+#ifdef TILE_NET_GSO
+ /* We support GSO. */
+ dev->features |= NETIF_F_GSO;
+#endif
+
+#ifdef TILE_NET_TSO
+ /* We support TSO. */
+ dev->features |= NETIF_F_TSO;
+#endif
+
+ dev->tx_queue_len = TILE_NET_TX_QUEUE_LEN;
+
+ dev->mtu = 1500;
+}
+
+
+/* Allocate the device structure, register the device, and obtain the
+ * MAC address from the hypervisor.
+ */
+static void tile_net_dev_init(const char *name, const uint8_t* mac)
+{
+ int ret;
+ int i;
+ int nz_addr = 0;
+ struct net_device *dev;
+ struct tile_net_priv *priv;
+
+ /* HACK: Ignore "loop" links. */
+ if (strncmp(name, "loop", 4) == 0)
+ return;
+
+ /* Allocate the device structure. This allocates "priv", calls
+ * tile_net_setup(), and saves "name". Normally, "name" is a
+ * template, instantiated by register_netdev(), but not for us.
+ */
+ dev = alloc_netdev(sizeof(*priv), name, tile_net_setup);
+ if (!dev) {
+ pr_err("alloc_netdev(%s) failed\n", name);
+ return;
+ }
+
+ priv = netdev_priv(dev);
+
+ /* Initialize "priv". */
+
+ memset(priv, 0, sizeof(*priv));
+
+ priv->dev = dev;
+
+ priv->channel = priv->loopify_channel = priv->echannel = -1;
+
+ /* Register the network device. */
+ ret = register_netdev(dev);
+ if (ret) {
+ netdev_err(dev, "register_netdev failed %d\n", ret);
+ free_netdev(dev);
+ return;
+ }
+
+ /* Get the MAC address and set it in the device struct; this must
+ * be done before the device is opened. If the MAC is all zeroes,
+ * we use a random address, since we're probably on the simulator.
+ */
+ for (i = 0; i < 6; i++)
+ nz_addr |= mac[i];
+
+ if (nz_addr) {
+ memcpy(dev->dev_addr, mac, 6);
+ dev->addr_len = 6;
+ } else {
+ random_ether_addr(dev->dev_addr);
+ }
+}
+
+
+/* Module initialization. */
+static int __init tile_net_init_module(void)
+{
+ int i;
+ char name[GXIO_MPIPE_LINK_NAME_LEN];
+ uint8_t mac[6];
+
+ pr_info("Tilera Network Driver\n");
+
+ mutex_init(&tile_net_devs_for_channel_mutex);
+
+ /* Initialize each CPU. */
+ on_each_cpu(tile_net_prepare_cpu, NULL, 1);
+
+ /* Find out what devices we have, and initialize them. */
+ for (i = 0; gxio_mpipe_link_enumerate_mac(i, name, mac) >= 0; i++)
+ tile_net_dev_init(name, mac);
+
+ return 0;
+}
+
+module_init(tile_net_init_module);
--
1.6.5.2
^ permalink raw reply related
* [PATCH v10] tilegx network driver: initial support
From: Chris Metcalf @ 2012-04-06 20:42 UTC (permalink / raw)
To: David Miller, eric.dumazet, bhutchings, arnd, linux-kernel,
netdev
In-Reply-To: <20120606.115440.1245419453265419850.davem@davemloft.net>
This change adds support for the tilegx network driver based on the
GXIO IORPC support in the tilegx software stack, using the on-chip
mPIPE packet processing engine.
Signed-off-by: Chris Metcalf <cmetcalf@tilera.com>
---
This version makes the driver multi-queued and support non-zero
tx_queue_len. I also made a couple of magic numbers into #defines.
I skimmed the tg3.c driver, but didn't see any other obvious
changes that would be appropriate.
drivers/net/ethernet/tile/Kconfig | 2 +
drivers/net/ethernet/tile/Makefile | 4 +-
drivers/net/ethernet/tile/tilegx.c | 1898 ++++++++++++++++++++++++++++++++++++
3 files changed, 1902 insertions(+), 2 deletions(-)
create mode 100644 drivers/net/ethernet/tile/tilegx.c
diff --git a/drivers/net/ethernet/tile/Kconfig b/drivers/net/ethernet/tile/Kconfig
index 2d9218f..098b1c4 100644
--- a/drivers/net/ethernet/tile/Kconfig
+++ b/drivers/net/ethernet/tile/Kconfig
@@ -7,6 +7,8 @@ config TILE_NET
depends on TILE
default y
select CRC32
+ select TILE_GXIO_MPIPE if TILEGX
+ select HIGH_RES_TIMERS if TILEGX
---help---
This is a standard Linux network device driver for the
on-chip Tilera Gigabit Ethernet and XAUI interfaces.
diff --git a/drivers/net/ethernet/tile/Makefile b/drivers/net/ethernet/tile/Makefile
index f634f14..0ef9eef 100644
--- a/drivers/net/ethernet/tile/Makefile
+++ b/drivers/net/ethernet/tile/Makefile
@@ -4,7 +4,7 @@
obj-$(CONFIG_TILE_NET) += tile_net.o
ifdef CONFIG_TILEGX
-tile_net-objs := tilegx.o mpipe.o iorpc_mpipe.o dma_queue.o
+tile_net-y := tilegx.o
else
-tile_net-objs := tilepro.o
+tile_net-y := tilepro.o
endif
diff --git a/drivers/net/ethernet/tile/tilegx.c b/drivers/net/ethernet/tile/tilegx.c
new file mode 100644
index 0000000..ee7556a
--- /dev/null
+++ b/drivers/net/ethernet/tile/tilegx.c
@@ -0,0 +1,1898 @@
+/*
+ * Copyright 2012 Tilera Corporation. All Rights Reserved.
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public License
+ * as published by the Free Software Foundation, version 2.
+ *
+ * This program is distributed in the hope that it will be useful, but
+ * WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY OR FITNESS FOR A PARTICULAR PURPOSE, GOOD TITLE or
+ * NON INFRINGEMENT. See the GNU General Public License for
+ * more details.
+ */
+
+#include <linux/module.h>
+#include <linux/init.h>
+#include <linux/moduleparam.h>
+#include <linux/sched.h>
+#include <linux/kernel.h> /* printk() */
+#include <linux/slab.h> /* kmalloc() */
+#include <linux/errno.h> /* error codes */
+#include <linux/types.h> /* size_t */
+#include <linux/interrupt.h>
+#include <linux/in.h>
+#include <linux/irq.h>
+#include <linux/netdevice.h> /* struct device, and other headers */
+#include <linux/etherdevice.h> /* eth_type_trans */
+#include <linux/skbuff.h>
+#include <linux/ioctl.h>
+#include <linux/cdev.h>
+#include <linux/hugetlb.h>
+#include <linux/in6.h>
+#include <linux/timer.h>
+#include <linux/hrtimer.h>
+#include <linux/ktime.h>
+#include <linux/io.h>
+#include <linux/ctype.h>
+#include <linux/ip.h>
+#include <linux/tcp.h>
+
+#include <asm/checksum.h>
+#include <asm/homecache.h>
+#include <gxio/mpipe.h>
+#include <arch/sim.h>
+
+/* Default transmit lockup timeout period, in jiffies. */
+#define TILE_NET_TIMEOUT (5 * HZ)
+
+/* The maximum number of distinct channels (idesc.channel is 5 bits). */
+#define TILE_NET_CHANNELS 32
+
+/* Maximum number of idescs to handle per "poll". */
+#define TILE_NET_BATCH 128
+
+/* Maximum number of packets to handle per "poll". */
+#define TILE_NET_WEIGHT 64
+
+/* Number of entries in each iqueue. */
+#define IQUEUE_ENTRIES 512
+
+/* Number of entries in each equeue. */
+#define EQUEUE_ENTRIES 2048
+
+/* Total header bytes per equeue slot. Must be big enough for 2 bytes
+ * of NET_IP_ALIGN alignment, plus 14 bytes (?) of L2 header, plus up to
+ * 60 bytes of actual TCP header. We round up to align to cache lines.
+ */
+#define HEADER_BYTES 128
+
+/* Maximum completions per cpu per device (must be a power of two).
+ * ISSUE: What is the right number here? If this is too small, then
+ * egress might block waiting for free space in a completions array.
+ * ISSUE: At the least, allocate these only for initialized echannels.
+ */
+#define TILE_NET_MAX_COMPS 64
+
+#define MAX_FRAGS (MAX_SKB_FRAGS + 1)
+
+/* Size of completions data to allocate.
+ * ISSUE: Probably more than needed since we don't use all the channels.
+ */
+#define COMPS_SIZE (TILE_NET_CHANNELS * sizeof(struct tile_net_comps))
+
+/* Size of NotifRing data to allocate. */
+#define NOTIF_RING_SIZE (IQUEUE_ENTRIES * sizeof(gxio_mpipe_idesc_t))
+
+/* Timeout to wake the per-device TX timer after we stop the queue.
+ * We don't want the timeout too short (adds overhead, and might end
+ * up causing stop/wake/stop/wake cycles) or too long (affects performance).
+ * For the 10 Gb NIC, 30 usec means roughly 30+ 1500-byte packets.
+ */
+#define TX_TIMER_DELAY_USEC 30
+
+/* Timeout to wake the per-cpu egress timer to free completions. */
+#define EGRESS_TIMER_DELAY_USEC 1000
+
+MODULE_AUTHOR("Tilera Corporation");
+MODULE_LICENSE("GPL");
+
+/* A "packet fragment" (a chunk of memory). */
+struct frag {
+ void *buf;
+ size_t length;
+};
+
+/* A single completion. */
+struct tile_net_comp {
+ /* The "complete_count" when the completion will be complete. */
+ s64 when;
+ /* The buffer to be freed when the completion is complete. */
+ struct sk_buff *skb;
+};
+
+/* The completions for a given cpu and echannel. */
+struct tile_net_comps {
+ /* The completions. */
+ struct tile_net_comp comp_queue[TILE_NET_MAX_COMPS];
+ /* The number of completions used. */
+ unsigned long comp_next;
+ /* The number of completions freed. */
+ unsigned long comp_last;
+};
+
+/* The transmit wake timer for a given cpu and echannel. */
+struct tile_net_tx_wake {
+ struct hrtimer timer;
+ struct net_device *dev;
+};
+
+/* Info for a specific cpu. */
+struct tile_net_info {
+ /* The NAPI struct. */
+ struct napi_struct napi;
+ /* Packet queue. */
+ gxio_mpipe_iqueue_t iqueue;
+ /* Our cpu. */
+ int my_cpu;
+ /* True if iqueue is valid. */
+ bool has_iqueue;
+ /* NAPI flags. */
+ bool napi_added;
+ bool napi_enabled;
+ /* Number of small sk_buffs which must still be provided. */
+ unsigned int num_needed_small_buffers;
+ /* Number of large sk_buffs which must still be provided. */
+ unsigned int num_needed_large_buffers;
+ /* A timer for handling egress completions. */
+ struct hrtimer egress_timer;
+ /* True if "egress_timer" is scheduled. */
+ bool egress_timer_scheduled;
+ /* Comps for each egress channel. */
+ struct tile_net_comps *comps_for_echannel[TILE_NET_CHANNELS];
+ /* Transmit wake timer for each egress channel. */
+ struct tile_net_tx_wake tx_wake[TILE_NET_CHANNELS];
+};
+
+/* Info for egress on a particular egress channel. */
+struct tile_net_egress {
+ /* The "equeue". */
+ gxio_mpipe_equeue_t *equeue;
+ /* The headers for TSO. */
+ unsigned char *headers;
+};
+
+/* Info for a specific device. */
+struct tile_net_priv {
+ /* Our network device. */
+ struct net_device *dev;
+ /* The primary link. */
+ gxio_mpipe_link_t link;
+ /* The primary channel, if open, else -1. */
+ int channel;
+ /* The "loopify" egress link, if needed. */
+ gxio_mpipe_link_t loopify_link;
+ /* The "loopify" egress channel, if open, else -1. */
+ int loopify_channel;
+ /* The egress channel (channel or loopify_channel). */
+ int echannel;
+ /* Total stats. */
+ struct net_device_stats stats;
+};
+
+/* Egress info, indexed by "priv->echannel" (lazily created as needed). */
+static struct tile_net_egress egress_for_echannel[TILE_NET_CHANNELS];
+
+/* Devices currently associated with each channel.
+ * NOTE: The array entry can become NULL after ifconfig down, but
+ * we do not free the underlying net_device structures, so it is
+ * safe to use a pointer after reading it from this array.
+ */
+static struct net_device *tile_net_devs_for_channel[TILE_NET_CHANNELS];
+
+/* A mutex for "tile_net_devs_for_channel". */
+static DEFINE_MUTEX(tile_net_devs_for_channel_mutex);
+
+/* The per-cpu info. */
+static DEFINE_PER_CPU(struct tile_net_info, per_cpu_info);
+
+/* The "context" for all devices. */
+static gxio_mpipe_context_t context;
+
+/* Buffer sizes and mpipe enum codes for buffer stacks.
+ * See arch/tile/include/gxio/mpipe.h for the set of possible values.
+ */
+#define BUFFER_SIZE_SMALL_ENUM GXIO_MPIPE_BUFFER_SIZE_128
+#define BUFFER_SIZE_SMALL 128
+#define BUFFER_SIZE_LARGE_ENUM GXIO_MPIPE_BUFFER_SIZE_1664
+#define BUFFER_SIZE_LARGE 1664
+
+/* The small/large "buffer stacks". */
+static int small_buffer_stack = -1;
+static int large_buffer_stack = -1;
+
+/* Amount of memory allocated for each buffer stack. */
+static size_t buffer_stack_size;
+
+/* The actual memory allocated for the buffer stacks. */
+static void *small_buffer_stack_va;
+static void *large_buffer_stack_va;
+
+/* The buckets. */
+static int first_bucket = -1;
+static int num_buckets = 1;
+
+/* The ingress irq. */
+static int ingress_irq = -1;
+
+/* Text value of tile_net.cpus if passed as a module parameter. */
+static char *network_cpus_string;
+
+/* The actual cpus in "network_cpus". */
+static struct cpumask network_cpus_map;
+
+/* If "loopify=LINK" was specified, this is "LINK". */
+static char *loopify_link_name;
+
+/* If "tile_net.custom" was specified, this is non-NULL. */
+static char *custom_str;
+
+/* The "tile_net.cpus" argument specifies the cpus that are dedicated
+ * to handle ingress packets.
+ *
+ * The parameter should be in the form "tile_net.cpus=m-n[,x-y]", where
+ * m, n, x, y are integer numbers that represent the cpus that can be
+ * neither a dedicated cpu nor a dataplane cpu.
+ */
+static bool network_cpus_init(void)
+{
+ char buf[1024];
+ int rc;
+
+ if (network_cpus_string == NULL)
+ return false;
+
+ rc = cpulist_parse_crop(network_cpus_string, &network_cpus_map);
+ if (rc != 0) {
+ pr_warn("tile_net.cpus=%s: malformed cpu list\n",
+ network_cpus_string);
+ return false;
+ }
+
+ /* Remove dedicated cpus. */
+ cpumask_and(&network_cpus_map, &network_cpus_map, cpu_possible_mask);
+
+ if (cpumask_empty(&network_cpus_map)) {
+ pr_warn("Ignoring empty tile_net.cpus='%s'.\n",
+ network_cpus_string);
+ return false;
+ }
+
+ cpulist_scnprintf(buf, sizeof(buf), &network_cpus_map);
+ pr_info("Linux network CPUs: %s\n", buf);
+ return true;
+}
+
+module_param_named(cpus, network_cpus_string, charp, 0444);
+MODULE_PARM_DESC(cpus, "cpulist of cores that handle network interrupts");
+
+/* The "tile_net.loopify=LINK" argument causes the named device to
+ * actually use "loop0" for ingress, and "loop1" for egress. This
+ * allows an app to sit between the actual link and linux, passing
+ * (some) packets along to linux, and forwarding (some) packets sent
+ * out by linux.
+ */
+module_param_named(loopify, loopify_link_name, charp, 0444);
+MODULE_PARM_DESC(loopify, "name the device to use loop0/1 for ingress/egress");
+
+/* The "tile_net.custom" argument causes us to ignore the "conventional"
+ * classifier metadata, in particular, the "l2_offset".
+ */
+module_param_named(custom, custom_str, charp, 0444);
+MODULE_PARM_DESC(custom, "indicates a (heavily) customized classifier");
+
+/* Atomically update a statistics field.
+ * Note that on TILE-Gx, this operation is fire-and-forget on the
+ * issuing core (single-cycle dispatch) and takes only a few cycles
+ * longer than a regular store when the request reaches the home cache.
+ * No expensive bus management overhead is required.
+ */
+static void tile_net_stats_add(unsigned long value, unsigned long *field)
+{
+ BUILD_BUG_ON(sizeof(atomic_long_t) != sizeof(unsigned long));
+ atomic_long_add(value, (atomic_long_t *)field);
+}
+
+/* Allocate and push a buffer. */
+static bool tile_net_provide_buffer(bool small)
+{
+ int stack = small ? small_buffer_stack : large_buffer_stack;
+ const unsigned long buffer_alignment = 128;
+ struct sk_buff *skb;
+ int len;
+
+ len = sizeof(struct sk_buff **) + buffer_alignment;
+ len += (small ? BUFFER_SIZE_SMALL : BUFFER_SIZE_LARGE);
+ skb = dev_alloc_skb(len);
+ if (skb == NULL)
+ return false;
+
+ /* Make room for a back-pointer to 'skb' and guarantee alignment. */
+ skb_reserve(skb, sizeof(struct sk_buff **));
+ skb_reserve(skb, -(long)skb->data & (buffer_alignment - 1));
+
+ /* Save a back-pointer to 'skb'. */
+ *(struct sk_buff **)(skb->data - sizeof(struct sk_buff **)) = skb;
+
+ /* Make sure "skb" and the back-pointer have been flushed. */
+ wmb();
+
+ gxio_mpipe_push_buffer(&context, stack,
+ (void *)va_to_tile_io_addr(skb->data));
+
+ return true;
+}
+
+/* Convert a raw mpipe buffer to its matching skb pointer. */
+static struct sk_buff *mpipe_buf_to_skb(void *va)
+{
+ /* Acquire the associated "skb". */
+ struct sk_buff **skb_ptr = va - sizeof(*skb_ptr);
+ struct sk_buff *skb = *skb_ptr;
+
+ /* Paranoia. */
+ if (skb->data != va) {
+ /* Panic here since there's a reasonable chance
+ * that corrupt buffers means generic memory
+ * corruption, with unpredictable system effects.
+ */
+ panic("Corrupt linux buffer! va=%p, skb=%p, skb->data=%p",
+ va, skb, skb->data);
+ }
+
+ return skb;
+}
+
+static void tile_net_pop_all_buffers(int stack)
+{
+ for (;;) {
+ tile_io_addr_t addr =
+ (tile_io_addr_t)gxio_mpipe_pop_buffer(&context, stack);
+ if (addr == 0)
+ break;
+ dev_kfree_skb_irq(mpipe_buf_to_skb(tile_io_addr_to_va(addr)));
+ }
+}
+
+/* Provide linux buffers to mPIPE. */
+static void tile_net_provide_needed_buffers(void)
+{
+ struct tile_net_info *info = &__get_cpu_var(per_cpu_info);
+
+ while (info->num_needed_small_buffers != 0) {
+ if (!tile_net_provide_buffer(true))
+ goto oops;
+ info->num_needed_small_buffers--;
+ }
+
+ while (info->num_needed_large_buffers != 0) {
+ if (!tile_net_provide_buffer(false))
+ goto oops;
+ info->num_needed_large_buffers--;
+ }
+
+ return;
+
+oops:
+ /* Add a description to the page allocation failure dump. */
+ pr_notice("Tile %d still needs some buffers\n", info->my_cpu);
+}
+
+static inline bool filter_packet(struct net_device *dev, void *buf)
+{
+ /* Filter packets received before we're up. */
+ if (dev == NULL || !(dev->flags & IFF_UP))
+ return true;
+
+ /* Filter out packets that aren't for us. */
+ if (!(dev->flags & IFF_PROMISC) &&
+ !is_multicast_ether_addr(buf) &&
+ compare_ether_addr(dev->dev_addr, buf) != 0)
+ return true;
+
+ return false;
+}
+
+static void tile_net_receive_skb(struct net_device *dev, struct sk_buff *skb,
+ gxio_mpipe_idesc_t *idesc, unsigned long len)
+{
+ struct tile_net_info *info = &__get_cpu_var(per_cpu_info);
+ struct tile_net_priv *priv = netdev_priv(dev);
+
+ /* Encode the actual packet length. */
+ skb_put(skb, len);
+
+ skb->protocol = eth_type_trans(skb, dev);
+
+ /* Acknowledge "good" hardware checksums. */
+ if (idesc->cs && idesc->csum_seed_val == 0xFFFF)
+ skb->ip_summed = CHECKSUM_UNNECESSARY;
+
+ netif_receive_skb(skb);
+
+ /* Update stats. */
+ tile_net_stats_add(1, &priv->stats.rx_packets);
+ tile_net_stats_add(len, &priv->stats.rx_bytes);
+
+ /* Need a new buffer. */
+ if (idesc->size == BUFFER_SIZE_SMALL_ENUM)
+ info->num_needed_small_buffers++;
+ else
+ info->num_needed_large_buffers++;
+}
+
+/* Handle a packet. Return true if "processed", false if "filtered". */
+static bool tile_net_handle_packet(gxio_mpipe_idesc_t *idesc)
+{
+ struct tile_net_info *info = &__get_cpu_var(per_cpu_info);
+ struct net_device *dev = tile_net_devs_for_channel[idesc->channel];
+ uint8_t l2_offset;
+ void *va;
+ void *buf;
+ unsigned long len;
+ bool filter;
+
+ /* Drop packets for which no buffer was available.
+ * NOTE: This happens under heavy load.
+ */
+ if (idesc->be) {
+ struct tile_net_priv *priv = netdev_priv(dev);
+ tile_net_stats_add(1, &priv->stats.rx_dropped);
+ gxio_mpipe_iqueue_consume(&info->iqueue, idesc);
+ if (net_ratelimit())
+ pr_info("Dropping packet (insufficient buffers).\n");
+ return false;
+ }
+
+ /* Get the "l2_offset", if allowed. */
+ l2_offset = custom_str ? 0 : gxio_mpipe_idesc_get_l2_offset(idesc);
+
+ /* Get the raw buffer VA (includes "headroom"). */
+ va = tile_io_addr_to_va((unsigned long)(long)idesc->va);
+
+ /* Get the actual packet start/length. */
+ buf = va + l2_offset;
+ len = idesc->l2_size - l2_offset;
+
+ /* Point "va" at the raw buffer. */
+ va -= NET_IP_ALIGN;
+
+ filter = filter_packet(dev, buf);
+ if (filter) {
+ gxio_mpipe_iqueue_drop(&info->iqueue, idesc);
+ } else {
+ struct sk_buff *skb = mpipe_buf_to_skb(va);
+
+ /* Skip headroom, and any custom header. */
+ skb_reserve(skb, NET_IP_ALIGN + l2_offset);
+
+ tile_net_receive_skb(dev, skb, idesc, len);
+ }
+
+ gxio_mpipe_iqueue_consume(&info->iqueue, idesc);
+ return !filter;
+}
+
+/* Handle some packets for the current CPU.
+ *
+ * This function handles up to TILE_NET_BATCH idescs per call.
+ *
+ * ISSUE: Since we do not provide new buffers until this function is
+ * complete, we must initially provide enough buffers for each network
+ * cpu to fill its iqueue and also its batched idescs.
+ *
+ * ISSUE: The "rotting packet" race condition occurs if a packet
+ * arrives after the queue appears to be empty, and before the
+ * hypervisor interrupt is re-enabled.
+ */
+static int tile_net_poll(struct napi_struct *napi, int budget)
+{
+ struct tile_net_info *info = &__get_cpu_var(per_cpu_info);
+ unsigned int work = 0;
+ gxio_mpipe_idesc_t *idesc;
+ int i, n;
+
+ /* Process packets. */
+ while ((n = gxio_mpipe_iqueue_try_peek(&info->iqueue, &idesc)) > 0) {
+ for (i = 0; i < n; i++) {
+ if (i == TILE_NET_BATCH)
+ goto done;
+ if (tile_net_handle_packet(idesc + i)) {
+ if (++work >= budget)
+ goto done;
+ }
+ }
+ }
+
+ /* There are no packets left. */
+ napi_complete(&info->napi);
+
+ /* Re-enable hypervisor interrupts. */
+ gxio_mpipe_enable_notif_ring_interrupt(&context, info->iqueue.ring);
+
+ /* HACK: Avoid the "rotting packet" problem. */
+ if (gxio_mpipe_iqueue_try_peek(&info->iqueue, &idesc) > 0)
+ napi_schedule(&info->napi);
+
+ /* ISSUE: Handle completions? */
+
+done:
+ tile_net_provide_needed_buffers();
+
+ return work;
+}
+
+/* Handle an ingress interrupt on the current cpu. */
+static irqreturn_t tile_net_handle_ingress_irq(int irq, void *unused)
+{
+ struct tile_net_info *info = &__get_cpu_var(per_cpu_info);
+ napi_schedule(&info->napi);
+ return IRQ_HANDLED;
+}
+
+/* Free some completions. This must be called with interrupts blocked. */
+static int tile_net_free_comps(gxio_mpipe_equeue_t *equeue,
+ struct tile_net_comps *comps,
+ int limit, bool force_update)
+{
+ int n = 0;
+ while (comps->comp_last < comps->comp_next) {
+ unsigned int cid = comps->comp_last % TILE_NET_MAX_COMPS;
+ struct tile_net_comp *comp = &comps->comp_queue[cid];
+ if (!gxio_mpipe_equeue_is_complete(equeue, comp->when,
+ force_update || n == 0))
+ break;
+ dev_kfree_skb_irq(comp->skb);
+ comps->comp_last++;
+ if (++n == limit)
+ break;
+ }
+ return n;
+}
+
+/* Add a completion. This must be called with interrupts blocked.
+ * tile_net_equeue_try_reserve() will have ensured a free completion entry.
+ */
+static void add_comp(gxio_mpipe_equeue_t *equeue,
+ struct tile_net_comps *comps,
+ uint64_t when, struct sk_buff *skb)
+{
+ int cid = comps->comp_next % TILE_NET_MAX_COMPS;
+ comps->comp_queue[cid].when = when;
+ comps->comp_queue[cid].skb = skb;
+ comps->comp_next++;
+}
+
+static void tile_net_schedule_tx_wake_timer(struct net_device *dev)
+{
+ struct tile_net_info *info = &__get_cpu_var(per_cpu_info);
+ struct tile_net_priv *priv = netdev_priv(dev);
+
+ hrtimer_start(&info->tx_wake[priv->echannel].timer,
+ ktime_set(0, TX_TIMER_DELAY_USEC * 1000UL),
+ HRTIMER_MODE_REL_PINNED);
+}
+
+static enum hrtimer_restart tile_net_handle_tx_wake_timer(struct hrtimer *t)
+{
+ struct tile_net_tx_wake *tx_wake =
+ container_of(t, struct tile_net_tx_wake, timer);
+ netif_wake_subqueue(tx_wake->dev, smp_processor_id());
+ return HRTIMER_NORESTART;
+}
+
+/* Make sure the egress timer is scheduled. */
+static void tile_net_schedule_egress_timer(void)
+{
+ struct tile_net_info *info = &__get_cpu_var(per_cpu_info);
+
+ if (!info->egress_timer_scheduled) {
+ hrtimer_start(&info->egress_timer,
+ ktime_set(0, EGRESS_TIMER_DELAY_USEC * 1000UL),
+ HRTIMER_MODE_REL_PINNED);
+ info->egress_timer_scheduled = true;
+ }
+}
+
+/* The "function" for "info->egress_timer".
+ *
+ * This timer will reschedule itself as long as there are any pending
+ * completions expected for this tile.
+ */
+static enum hrtimer_restart tile_net_handle_egress_timer(struct hrtimer *t)
+{
+ struct tile_net_info *info = &__get_cpu_var(per_cpu_info);
+ unsigned long irqflags;
+ bool pending = false;
+ int i;
+
+ local_irq_save(irqflags);
+
+ /* The timer is no longer scheduled. */
+ info->egress_timer_scheduled = false;
+
+ /* Free all possible comps for this tile. */
+ for (i = 0; i < TILE_NET_CHANNELS; i++) {
+ struct tile_net_egress *egress = &egress_for_echannel[i];
+ struct tile_net_comps *comps = info->comps_for_echannel[i];
+ if (comps->comp_last >= comps->comp_next)
+ continue;
+ tile_net_free_comps(egress->equeue, comps, -1, true);
+ pending = pending || (comps->comp_last < comps->comp_next);
+ }
+
+ /* Reschedule timer if needed. */
+ if (pending)
+ tile_net_schedule_egress_timer();
+
+ local_irq_restore(irqflags);
+
+ return HRTIMER_NORESTART;
+}
+
+/* Helper function for "tile_net_update()".
+ * "dev" (i.e. arg) is the device being brought up or down,
+ * or NULL if all devices are now down.
+ */
+static void tile_net_update_cpu(void *arg)
+{
+ struct tile_net_info *info = &__get_cpu_var(per_cpu_info);
+ struct net_device *dev = arg;
+
+ if (!info->has_iqueue)
+ return;
+
+ if (dev != NULL) {
+ if (!info->napi_added) {
+ netif_napi_add(dev, &info->napi,
+ tile_net_poll, TILE_NET_WEIGHT);
+ info->napi_added = true;
+ }
+ if (!info->napi_enabled) {
+ napi_enable(&info->napi);
+ info->napi_enabled = true;
+ }
+ enable_percpu_irq(ingress_irq, 0);
+ } else {
+ disable_percpu_irq(ingress_irq);
+ if (info->napi_enabled) {
+ napi_disable(&info->napi);
+ info->napi_enabled = false;
+ }
+ /* FIXME: Drain the iqueue. */
+ }
+}
+
+/* Helper function for tile_net_open() and tile_net_stop().
+ * Always called under tile_net_devs_for_channel_mutex.
+ */
+static int tile_net_update(struct net_device *dev)
+{
+ static gxio_mpipe_rules_t rules; /* too big to fit on the stack */
+ bool saw_channel = false;
+ int channel;
+ int rc;
+ int cpu;
+
+ gxio_mpipe_rules_init(&rules, &context);
+
+ for (channel = 0; channel < TILE_NET_CHANNELS; channel++) {
+ if (tile_net_devs_for_channel[channel] == NULL)
+ continue;
+ if (!saw_channel) {
+ saw_channel = true;
+ gxio_mpipe_rules_begin(&rules, first_bucket,
+ num_buckets, NULL);
+ gxio_mpipe_rules_set_headroom(&rules, NET_IP_ALIGN);
+ }
+ gxio_mpipe_rules_add_channel(&rules, channel);
+ }
+
+ /* NOTE: This can fail if there is no classifier.
+ * ISSUE: Can anything else cause it to fail?
+ */
+ rc = gxio_mpipe_rules_commit(&rules);
+ if (rc != 0) {
+ netdev_warn(dev, "gxio_mpipe_rules_commit failed: %d\n", rc);
+ return -EIO;
+ }
+
+ /* Update all cpus, sequentially (to protect "netif_napi_add()"). */
+ for_each_online_cpu(cpu)
+ smp_call_function_single(cpu, tile_net_update_cpu,
+ (saw_channel ? dev : NULL), 1);
+
+ /* HACK: Allow packets to flow in the simulator. */
+ if (saw_channel)
+ sim_enable_mpipe_links(0, -1);
+
+ return 0;
+}
+
+/* Allocate and initialize mpipe buffer stacks, and register them in
+ * the mPIPE TLBs, for both small and large packet sizes.
+ * This routine supports tile_net_init_mpipe(), below.
+ */
+static int init_buffer_stacks(struct net_device *dev, int num_buffers)
+{
+ pte_t hash_pte = pte_set_home((pte_t) { 0 }, PAGE_HOME_HASH);
+ int rc;
+
+ /* Compute stack bytes; we round up to 64KB and then use
+ * alloc_pages() so we get the required 64KB alignment as well.
+ */
+ buffer_stack_size =
+ ALIGN(gxio_mpipe_calc_buffer_stack_bytes(num_buffers),
+ 64 * 1024);
+
+ /* Allocate two buffer stack indices. */
+ rc = gxio_mpipe_alloc_buffer_stacks(&context, 2, 0, 0);
+ if (rc < 0) {
+ netdev_err(dev, "gxio_mpipe_alloc_buffer_stacks failed: %d\n",
+ rc);
+ return rc;
+ }
+ small_buffer_stack = rc;
+ large_buffer_stack = rc + 1;
+
+ /* Allocate the small memory stack. */
+ small_buffer_stack_va =
+ alloc_pages_exact(buffer_stack_size, GFP_KERNEL);
+ if (small_buffer_stack_va == NULL) {
+ netdev_err(dev,
+ "Could not alloc %zd bytes for buffer stacks\n",
+ buffer_stack_size);
+ return -ENOMEM;
+ }
+ rc = gxio_mpipe_init_buffer_stack(&context, small_buffer_stack,
+ BUFFER_SIZE_SMALL_ENUM,
+ small_buffer_stack_va,
+ buffer_stack_size, 0);
+ if (rc != 0) {
+ netdev_err(dev, "gxio_mpipe_init_buffer_stack: %d\n", rc);
+ return rc;
+ }
+ rc = gxio_mpipe_register_client_memory(&context, small_buffer_stack,
+ hash_pte, 0);
+ if (rc != 0) {
+ netdev_err(dev,
+ "gxio_mpipe_register_buffer_memory failed: %d\n",
+ rc);
+ return rc;
+ }
+
+ /* Allocate the large buffer stack. */
+ large_buffer_stack_va =
+ alloc_pages_exact(buffer_stack_size, GFP_KERNEL);
+ if (large_buffer_stack_va == NULL) {
+ netdev_err(dev,
+ "Could not alloc %zd bytes for buffer stacks\n",
+ buffer_stack_size);
+ return -ENOMEM;
+ }
+ rc = gxio_mpipe_init_buffer_stack(&context, large_buffer_stack,
+ BUFFER_SIZE_LARGE_ENUM,
+ large_buffer_stack_va,
+ buffer_stack_size, 0);
+ if (rc != 0) {
+ netdev_err(dev, "gxio_mpipe_init_buffer_stack failed: %d\n",
+ rc);
+ return rc;
+ }
+ rc = gxio_mpipe_register_client_memory(&context, large_buffer_stack,
+ hash_pte, 0);
+ if (rc != 0) {
+ netdev_err(dev,
+ "gxio_mpipe_register_buffer_memory failed: %d\n",
+ rc);
+ return rc;
+ }
+
+ return 0;
+}
+
+/* Allocate per-cpu resources (memory for completions and idescs).
+ * This routine supports tile_net_init_mpipe(), below.
+ */
+static int alloc_percpu_mpipe_resources(struct net_device *dev,
+ int cpu, int ring)
+{
+ struct tile_net_info *info = &per_cpu(per_cpu_info, cpu);
+ int order, i, rc;
+ struct page *page;
+ void *addr;
+
+ /* Allocate the "comps". */
+ order = get_order(COMPS_SIZE);
+ page = homecache_alloc_pages(GFP_KERNEL, order, cpu);
+ if (page == NULL) {
+ netdev_err(dev, "Failed to alloc %zd bytes comps memory\n",
+ COMPS_SIZE);
+ return -ENOMEM;
+ }
+ addr = pfn_to_kaddr(page_to_pfn(page));
+ memset(addr, 0, COMPS_SIZE);
+ for (i = 0; i < TILE_NET_CHANNELS; i++)
+ info->comps_for_echannel[i] =
+ addr + i * sizeof(struct tile_net_comps);
+
+ /* If this is a network cpu, create an iqueue. */
+ if (cpu_isset(cpu, network_cpus_map)) {
+ order = get_order(NOTIF_RING_SIZE);
+ page = homecache_alloc_pages(GFP_KERNEL, order, cpu);
+ if (page == NULL) {
+ netdev_err(dev,
+ "Failed to alloc %zd bytes iqueue memory\n",
+ NOTIF_RING_SIZE);
+ return -ENOMEM;
+ }
+ addr = pfn_to_kaddr(page_to_pfn(page));
+ rc = gxio_mpipe_iqueue_init(&info->iqueue, &context, ring++,
+ addr, NOTIF_RING_SIZE, 0);
+ if (rc < 0) {
+ netdev_err(dev,
+ "gxio_mpipe_iqueue_init failed: %d\n", rc);
+ return rc;
+ }
+ info->has_iqueue = true;
+ }
+
+ return ring;
+}
+
+/* Initialize NotifGroup and buckets.
+ * This routine supports tile_net_init_mpipe(), below.
+ */
+static int init_notif_group_and_buckets(struct net_device *dev,
+ int ring, int network_cpus_count)
+{
+ int group, rc;
+
+ /* Allocate one NotifGroup. */
+ rc = gxio_mpipe_alloc_notif_groups(&context, 1, 0, 0);
+ if (rc < 0) {
+ netdev_err(dev, "gxio_mpipe_alloc_notif_groups failed: %d\n",
+ rc);
+ return rc;
+ }
+ group = rc;
+
+ /* Initialize global num_buckets value. */
+ if (network_cpus_count > 4)
+ num_buckets = 256;
+ else if (network_cpus_count > 1)
+ num_buckets = 16;
+
+ /* Allocate some buckets, and set global first_bucket value. */
+ rc = gxio_mpipe_alloc_buckets(&context, num_buckets, 0, 0);
+ if (rc < 0) {
+ netdev_err(dev, "gxio_mpipe_alloc_buckets failed: %d\n", rc);
+ return rc;
+ }
+ first_bucket = rc;
+
+ /* Init group and buckets. */
+ rc = gxio_mpipe_init_notif_group_and_buckets(
+ &context, group, ring, network_cpus_count,
+ first_bucket, num_buckets,
+ GXIO_MPIPE_BUCKET_STICKY_FLOW_LOCALITY);
+ if (rc != 0) {
+ netdev_err(
+ dev,
+ "gxio_mpipe_init_notif_group_and_buckets failed: %d\n",
+ rc);
+ return rc;
+ }
+
+ return 0;
+}
+
+/* Create an irq and register it, then activate the irq and request
+ * interrupts on all cores. Note that "ingress_irq" being initialized
+ * is how we know not to call tile_net_init_mpipe() again.
+ * This routine supports tile_net_init_mpipe(), below.
+ */
+static int tile_net_setup_interrupts(struct net_device *dev)
+{
+ int cpu, rc;
+
+ rc = create_irq();
+ if (rc < 0) {
+ netdev_err(dev, "create_irq failed: %d\n", rc);
+ return rc;
+ }
+ ingress_irq = rc;
+ tile_irq_activate(ingress_irq, TILE_IRQ_PERCPU);
+ rc = request_irq(ingress_irq, tile_net_handle_ingress_irq,
+ 0, NULL, NULL);
+ if (rc != 0) {
+ netdev_err(dev, "request_irq failed: %d\n", rc);
+ destroy_irq(ingress_irq);
+ ingress_irq = -1;
+ return rc;
+ }
+
+ for_each_online_cpu(cpu) {
+ struct tile_net_info *info = &per_cpu(per_cpu_info, cpu);
+ if (info->has_iqueue) {
+ gxio_mpipe_request_notif_ring_interrupt(
+ &context, cpu_x(cpu), cpu_y(cpu),
+ 1, ingress_irq, info->iqueue.ring);
+ }
+ }
+
+ return 0;
+}
+
+/* Undo any state set up partially by a failed call to tile_net_init_mpipe. */
+static void tile_net_init_mpipe_fail(void)
+{
+ int cpu;
+
+ /* Do cleanups that require the mpipe context first. */
+ if (small_buffer_stack >= 0)
+ tile_net_pop_all_buffers(small_buffer_stack);
+ if (large_buffer_stack >= 0)
+ tile_net_pop_all_buffers(large_buffer_stack);
+
+ /* Destroy mpipe context so the hardware no longer owns any memory. */
+ gxio_mpipe_destroy(&context);
+
+ for_each_online_cpu(cpu) {
+ struct tile_net_info *info = &per_cpu(per_cpu_info, cpu);
+ free_pages((unsigned long)(info->comps_for_echannel[0]),
+ get_order(COMPS_SIZE));
+ info->comps_for_echannel[0] = NULL;
+ free_pages((unsigned long)(info->iqueue.idescs),
+ get_order(NOTIF_RING_SIZE));
+ info->iqueue.idescs = NULL;
+ }
+
+ if (small_buffer_stack_va)
+ free_pages_exact(small_buffer_stack_va, buffer_stack_size);
+ if (large_buffer_stack_va)
+ free_pages_exact(large_buffer_stack_va, buffer_stack_size);
+
+ small_buffer_stack_va = NULL;
+ large_buffer_stack_va = NULL;
+ large_buffer_stack = -1;
+ small_buffer_stack = -1;
+ first_bucket = -1;
+}
+
+/* The first time any tilegx network device is opened, we initialize
+ * the global mpipe state. If this step fails, we fail to open the
+ * device, but if it succeeds, we never need to do it again, and since
+ * tile_net can't be unloaded, we never undo it.
+ *
+ * Note that some resources in this path (buffer stack indices,
+ * bindings from init_buffer_stack, etc.) are hypervisor resources
+ * that are freed implicitly by gxio_mpipe_destroy().
+ */
+static int tile_net_init_mpipe(struct net_device *dev)
+{
+ int i, num_buffers, rc;
+ int cpu;
+ int first_ring, ring;
+ int network_cpus_count = cpus_weight(network_cpus_map);
+
+ if (!hash_default) {
+ netdev_err(dev, "Networking requires hash_default!\n");
+ return -EIO;
+ }
+
+ rc = gxio_mpipe_init(&context, 0);
+ if (rc != 0) {
+ netdev_err(dev, "gxio_mpipe_init failed: %d\n", rc);
+ return -EIO;
+ }
+
+ /* Set up the buffer stacks. */
+ num_buffers =
+ network_cpus_count * (IQUEUE_ENTRIES + TILE_NET_BATCH);
+ rc = init_buffer_stacks(dev, num_buffers);
+ if (rc != 0)
+ goto fail;
+
+ /* Provide initial buffers. */
+ rc = -ENOMEM;
+ for (i = 0; i < num_buffers; i++) {
+ if (!tile_net_provide_buffer(true)) {
+ netdev_err(dev, "Cannot allocate initial sk_bufs!\n");
+ goto fail;
+ }
+ }
+ for (i = 0; i < num_buffers; i++) {
+ if (!tile_net_provide_buffer(false)) {
+ netdev_err(dev, "Cannot allocate initial sk_bufs!\n");
+ goto fail;
+ }
+ }
+
+ /* Allocate one NotifRing for each network cpu. */
+ rc = gxio_mpipe_alloc_notif_rings(&context, network_cpus_count, 0, 0);
+ if (rc < 0) {
+ netdev_err(dev, "gxio_mpipe_alloc_notif_rings failed %d\n",
+ rc);
+ goto fail;
+ }
+
+ /* Init NotifRings per-cpu. */
+ first_ring = rc;
+ ring = first_ring;
+ for_each_online_cpu(cpu) {
+ rc = alloc_percpu_mpipe_resources(dev, cpu, ring);
+ if (rc < 0)
+ goto fail;
+ ring = rc;
+ }
+
+ /* Initialize NotifGroup and buckets. */
+ rc = init_notif_group_and_buckets(dev, first_ring, network_cpus_count);
+ if (rc != 0)
+ goto fail;
+
+ /* Create and enable interrupts. */
+ rc = tile_net_setup_interrupts(dev);
+ if (rc != 0)
+ goto fail;
+
+ return 0;
+
+fail:
+ tile_net_init_mpipe_fail();
+ return rc;
+}
+
+/* Create persistent egress info for a given egress channel.
+ * Note that this may be shared between, say, "gbe0" and "xgbe0".
+ * ISSUE: Defer header allocation until TSO is actually needed?
+ */
+static int tile_net_init_egress(struct net_device *dev, int echannel)
+{
+ struct page *headers_page, *edescs_page, *equeue_page;
+ gxio_mpipe_edesc_t *edescs;
+ gxio_mpipe_equeue_t *equeue;
+ unsigned char *headers;
+ int headers_order, edescs_order, equeue_order;
+ size_t edescs_size;
+ int edma;
+ int rc = -ENOMEM;
+
+ /* Only initialize once. */
+ if (egress_for_echannel[echannel].equeue != NULL)
+ return 0;
+
+ /* Allocate memory for the "headers". */
+ headers_order = get_order(EQUEUE_ENTRIES * HEADER_BYTES);
+ headers_page = alloc_pages(GFP_KERNEL, headers_order);
+ if (headers_page == NULL) {
+ netdev_warn(dev,
+ "Could not alloc %zd bytes for TSO headers.\n",
+ PAGE_SIZE << headers_order);
+ goto fail;
+ }
+ headers = pfn_to_kaddr(page_to_pfn(headers_page));
+
+ /* Allocate memory for the "edescs". */
+ edescs_size = EQUEUE_ENTRIES * sizeof(*edescs);
+ edescs_order = get_order(edescs_size);
+ edescs_page = alloc_pages(GFP_KERNEL, edescs_order);
+ if (edescs_page == NULL) {
+ netdev_warn(dev,
+ "Could not alloc %zd bytes for eDMA ring.\n",
+ edescs_size);
+ goto fail_headers;
+ }
+ edescs = pfn_to_kaddr(page_to_pfn(edescs_page));
+
+ /* Allocate memory for the "equeue". */
+ equeue_order = get_order(sizeof(*equeue));
+ equeue_page = alloc_pages(GFP_KERNEL, equeue_order);
+ if (equeue_page == NULL) {
+ netdev_warn(dev,
+ "Could not alloc %zd bytes for equeue info.\n",
+ PAGE_SIZE << equeue_order);
+ goto fail_edescs;
+ }
+ equeue = pfn_to_kaddr(page_to_pfn(equeue_page));
+
+ /* Allocate an edma ring. Note that in practice this can't
+ * fail, which is good, because we will leak an edma ring if so.
+ */
+ rc = gxio_mpipe_alloc_edma_rings(&context, 1, 0, 0);
+ if (rc < 0) {
+ netdev_warn(dev, "gxio_mpipe_alloc_edma_rings failed: %d\n",
+ rc);
+ goto fail_equeue;
+ }
+ edma = rc;
+
+ /* Initialize the equeue. */
+ rc = gxio_mpipe_equeue_init(equeue, &context, edma, echannel,
+ edescs, edescs_size, 0);
+ if (rc != 0) {
+ netdev_err(dev, "gxio_mpipe_equeue_init failed: %d\n", rc);
+ goto fail_equeue;
+ }
+
+ /* Done. */
+ egress_for_echannel[echannel].equeue = equeue;
+ egress_for_echannel[echannel].headers = headers;
+ return 0;
+
+fail_equeue:
+ __free_pages(equeue_page, equeue_order);
+
+fail_edescs:
+ __free_pages(edescs_page, edescs_order);
+
+fail_headers:
+ __free_pages(headers_page, headers_order);
+
+fail:
+ return rc;
+}
+
+/* Return channel number for a newly-opened link. */
+static int tile_net_link_open(struct net_device *dev, gxio_mpipe_link_t *link,
+ const char *link_name)
+{
+ int rc = gxio_mpipe_link_open(link, &context, link_name, 0);
+ if (rc < 0) {
+ netdev_err(dev, "Failed to open '%s'\n", link_name);
+ return rc;
+ }
+ rc = gxio_mpipe_link_channel(link);
+ if (rc < 0 || rc >= TILE_NET_CHANNELS) {
+ netdev_err(dev, "gxio_mpipe_link_channel bad value: %d\n", rc);
+ gxio_mpipe_link_close(link);
+ return -EINVAL;
+ }
+ return rc;
+}
+
+/* Help the kernel activate the given network interface. */
+static int tile_net_open(struct net_device *dev)
+{
+ struct tile_net_priv *priv = netdev_priv(dev);
+ int cpu, rc;
+
+ mutex_lock(&tile_net_devs_for_channel_mutex);
+
+ /* Do one-time initialization the first time any device is opened. */
+ if (ingress_irq < 0) {
+ rc = tile_net_init_mpipe(dev);
+ if (rc != 0)
+ goto fail;
+ }
+
+ /* Determine if this is the "loopify" device. */
+ if (unlikely((loopify_link_name != NULL) &&
+ !strcmp(dev->name, loopify_link_name))) {
+ rc = tile_net_link_open(dev, &priv->link, "loop0");
+ if (rc < 0)
+ goto fail;
+ priv->channel = rc;
+ rc = tile_net_link_open(dev, &priv->loopify_link, "loop1");
+ if (rc < 0)
+ goto fail;
+ priv->loopify_channel = rc;
+ priv->echannel = rc;
+ } else {
+ rc = tile_net_link_open(dev, &priv->link, dev->name);
+ if (rc < 0)
+ goto fail;
+ priv->channel = rc;
+ priv->echannel = rc;
+ }
+
+ /* Initialize egress info (if needed). Once ever, per echannel. */
+ rc = tile_net_init_egress(dev, priv->echannel);
+ if (rc != 0)
+ goto fail;
+
+ tile_net_devs_for_channel[priv->channel] = dev;
+
+ rc = tile_net_update(dev);
+ if (rc != 0)
+ goto fail;
+
+ mutex_unlock(&tile_net_devs_for_channel_mutex);
+
+ /* Initialize the transmit wake timer for this device for each cpu. */
+ for_each_online_cpu(cpu) {
+ struct tile_net_info *info = &per_cpu(per_cpu_info, cpu);
+ struct tile_net_tx_wake *tx_wake =
+ &info->tx_wake[priv->echannel];
+
+ hrtimer_init(&tx_wake->timer, CLOCK_MONOTONIC,
+ HRTIMER_MODE_REL);
+ tx_wake->timer.function = tile_net_handle_tx_wake_timer;
+ tx_wake->dev = dev;
+ }
+
+ for_each_online_cpu(cpu)
+ netif_start_subqueue(dev, cpu);
+ netif_carrier_on(dev);
+ return 0;
+
+fail:
+ if (priv->loopify_channel >= 0) {
+ if (gxio_mpipe_link_close(&priv->loopify_link) != 0)
+ netdev_warn(dev, "Failed to close loopify link!\n");
+ priv->loopify_channel = -1;
+ }
+ if (priv->channel >= 0) {
+ if (gxio_mpipe_link_close(&priv->link) != 0)
+ netdev_warn(dev, "Failed to close link!\n");
+ priv->channel = -1;
+ }
+ priv->echannel = -1;
+ tile_net_devs_for_channel[priv->channel] = NULL;
+ mutex_unlock(&tile_net_devs_for_channel_mutex);
+
+ /* Don't return raw gxio error codes to generic Linux. */
+ return (rc > -512) ? rc : -EIO;
+}
+
+/* Help the kernel deactivate the given network interface. */
+static int tile_net_stop(struct net_device *dev)
+{
+ struct tile_net_priv *priv = netdev_priv(dev);
+ int cpu;
+
+ for_each_online_cpu(cpu) {
+ struct tile_net_info *info = &per_cpu(per_cpu_info, cpu);
+ struct tile_net_tx_wake *tx_wake =
+ &info->tx_wake[priv->echannel];
+
+ hrtimer_cancel(&tx_wake->timer);
+ netif_stop_subqueue(dev, cpu);
+ }
+
+ mutex_lock(&tile_net_devs_for_channel_mutex);
+ tile_net_devs_for_channel[priv->channel] = NULL;
+ (void)tile_net_update(dev);
+ if (priv->loopify_channel >= 0) {
+ if (gxio_mpipe_link_close(&priv->loopify_link) != 0)
+ netdev_warn(dev, "Failed to close loopify link!\n");
+ priv->loopify_channel = -1;
+ }
+ if (priv->channel >= 0) {
+ if (gxio_mpipe_link_close(&priv->link) != 0)
+ netdev_warn(dev, "Failed to close link!\n");
+ priv->channel = -1;
+ }
+ priv->echannel = -1;
+ mutex_unlock(&tile_net_devs_for_channel_mutex);
+
+ return 0;
+}
+
+/* Determine the VA for a fragment. */
+static inline void *tile_net_frag_buf(skb_frag_t *f)
+{
+ unsigned long pfn = page_to_pfn(skb_frag_page(f));
+ return pfn_to_kaddr(pfn) + f->page_offset;
+}
+
+/* Acquire a completion entry and an egress slot, or if we can't,
+ * stop the queue and schedule the tx_wake timer.
+ */
+static s64 tile_net_equeue_try_reserve(struct net_device *dev,
+ struct tile_net_comps *comps,
+ gxio_mpipe_equeue_t *equeue,
+ int num_edescs)
+{
+ /* Try to acquire a completion entry. */
+ if (comps->comp_next - comps->comp_last < TILE_NET_MAX_COMPS - 1 ||
+ tile_net_free_comps(equeue, comps, 32, false) != 0) {
+
+ /* Try to acquire an egress slot. */
+ s64 slot = gxio_mpipe_equeue_try_reserve(equeue, num_edescs);
+ if (slot >= 0)
+ return slot;
+
+ /* Freeing some completions gives the equeue time to drain. */
+ tile_net_free_comps(equeue, comps, TILE_NET_MAX_COMPS, false);
+
+ slot = gxio_mpipe_equeue_try_reserve(equeue, num_edescs);
+ if (slot >= 0)
+ return slot;
+ }
+
+ /* Still nothing; give up and stop the queue for a short while. */
+ netif_stop_subqueue(dev, smp_processor_id());
+ tile_net_schedule_tx_wake_timer(dev);
+ return -1;
+}
+
+/* Determine how many edesc's are needed for TSO.
+ *
+ * Sometimes, if "sendfile()" requires copying, we will be called with
+ * "data" containing the header and payload, with "frags" being empty.
+ * Sometimes, for example when using NFS over TCP, a single segment can
+ * span 3 fragments. This requires special care.
+ */
+static int tso_count_edescs(struct sk_buff *skb)
+{
+ struct skb_shared_info *sh = skb_shinfo(skb);
+ unsigned int data_len = skb->data_len;
+ unsigned int p_len = sh->gso_size;
+ long f_id = -1; /* id of the current fragment */
+ long f_size = -1; /* size of the current fragment */
+ long f_used = -1; /* bytes used from the current fragment */
+ long n; /* size of the current piece of payload */
+ int num_edescs = 0;
+ int segment;
+
+ for (segment = 0; segment < sh->gso_segs; segment++) {
+
+ unsigned int p_used = 0;
+
+ /* One edesc for header and for each piece of the payload. */
+ for (num_edescs++; p_used < p_len; num_edescs++) {
+
+ /* Advance as needed. */
+ while (f_used >= f_size) {
+ f_id++;
+ f_size = sh->frags[f_id].size;
+ f_used = 0;
+ }
+
+ /* Use bytes from the current fragment. */
+ n = p_len - p_used;
+ if (n > f_size - f_used)
+ n = f_size - f_used;
+ f_used += n;
+ p_used += n;
+ }
+
+ /* The last segment may be less than gso_size. */
+ data_len -= p_len;
+ if (data_len < p_len)
+ p_len = data_len;
+ }
+
+ return num_edescs;
+}
+
+/* Prepare modified copies of the skbuff headers.
+ * FIXME: add support for IPv6.
+ */
+static void tso_headers_prepare(struct sk_buff *skb, unsigned char *headers,
+ s64 slot)
+{
+ struct skb_shared_info *sh = skb_shinfo(skb);
+ struct iphdr *ih;
+ struct tcphdr *th;
+ unsigned int data_len = skb->data_len;
+ unsigned char *data = skb->data;
+ unsigned int ih_off, th_off, sh_len, p_len;
+ unsigned int isum_seed, tsum_seed, id, seq;
+ long f_id = -1; /* id of the current fragment */
+ long f_size = -1; /* size of the current fragment */
+ long f_used = -1; /* bytes used from the current fragment */
+ long n; /* size of the current piece of payload */
+ int segment;
+
+ /* Locate original headers and compute various lengths. */
+ ih = ip_hdr(skb);
+ th = tcp_hdr(skb);
+ ih_off = skb_network_offset(skb);
+ th_off = skb_transport_offset(skb);
+ sh_len = th_off + tcp_hdrlen(skb);
+ p_len = sh->gso_size;
+
+ /* Set up seed values for IP and TCP csum and initialize id and seq. */
+ isum_seed = ((0xFFFF - ih->check) +
+ (0xFFFF - ih->tot_len) +
+ (0xFFFF - ih->id));
+ tsum_seed = th->check + (0xFFFF ^ htons(skb->len));
+ id = ntohs(ih->id);
+ seq = ntohl(th->seq);
+
+ /* Prepare all the headers. */
+ for (segment = 0; segment < sh->gso_segs; segment++) {
+ unsigned char *buf;
+ unsigned int p_used = 0;
+
+ /* Copy to the header memory for this segment. */
+ buf = headers + (slot % EQUEUE_ENTRIES) * HEADER_BYTES +
+ NET_IP_ALIGN;
+ memcpy(buf, data, sh_len);
+
+ /* Update copied ip header. */
+ ih = (struct iphdr *)(buf + ih_off);
+ ih->tot_len = htons(sh_len + p_len - ih_off);
+ ih->id = htons(id);
+ ih->check = csum_long(isum_seed + ih->tot_len +
+ ih->id) ^ 0xffff;
+
+ /* Update copied tcp header. */
+ th = (struct tcphdr *)(buf + th_off);
+ th->seq = htonl(seq);
+ th->check = csum_long(tsum_seed + htons(sh_len + p_len));
+ if (segment != sh->gso_segs - 1) {
+ th->fin = 0;
+ th->psh = 0;
+ }
+
+ /* Skip past the header. */
+ slot++;
+
+ /* Skip past the payload. */
+ while (p_used < p_len) {
+
+ /* Advance as needed. */
+ while (f_used >= f_size) {
+ f_id++;
+ f_size = sh->frags[f_id].size;
+ f_used = 0;
+ }
+
+ /* Use bytes from the current fragment. */
+ n = p_len - p_used;
+ if (n > f_size - f_used)
+ n = f_size - f_used;
+ f_used += n;
+ p_used += n;
+
+ slot++;
+ }
+
+ id++;
+ seq += p_len;
+
+ /* The last segment may be less than gso_size. */
+ data_len -= p_len;
+ if (data_len < p_len)
+ p_len = data_len;
+ }
+
+ /* Flush the headers so they are ready for hardware DMA. */
+ wmb();
+}
+
+/* Pass all the data to mpipe for egress. */
+static void tso_egress(struct net_device *dev, gxio_mpipe_equeue_t *equeue,
+ struct sk_buff *skb, unsigned char *headers, s64 slot)
+{
+ struct tile_net_priv *priv = netdev_priv(dev);
+ struct skb_shared_info *sh = skb_shinfo(skb);
+ unsigned int data_len = skb->data_len;
+ unsigned int p_len = sh->gso_size;
+ gxio_mpipe_edesc_t edesc_head = { { 0 } };
+ gxio_mpipe_edesc_t edesc_body = { { 0 } };
+ long f_id = -1; /* id of the current fragment */
+ long f_size = -1; /* size of the current fragment */
+ long f_used = -1; /* bytes used from the current fragment */
+ long n; /* size of the current piece of payload */
+ unsigned long tx_packets = 0, tx_bytes = 0;
+ unsigned int csum_start, sh_len;
+ int segment;
+
+ /* Prepare to egress the headers: set up header edesc. */
+ csum_start = skb_checksum_start_offset(skb);
+ sh_len = skb_transport_offset(skb) + tcp_hdrlen(skb);
+ edesc_head.csum = 1;
+ edesc_head.csum_start = csum_start;
+ edesc_head.csum_dest = csum_start + skb->csum_offset;
+ edesc_head.xfer_size = sh_len;
+
+ /* This is only used to specify the TLB. */
+ edesc_head.stack_idx = large_buffer_stack;
+ edesc_body.stack_idx = large_buffer_stack;
+
+ /* Egress all the edescs. */
+ for (segment = 0; segment < sh->gso_segs; segment++) {
+ void *va;
+ unsigned char *buf;
+ unsigned int p_used = 0;
+
+ /* Egress the header. */
+ buf = headers + (slot % EQUEUE_ENTRIES) * HEADER_BYTES +
+ NET_IP_ALIGN;
+ edesc_head.va = va_to_tile_io_addr(buf);
+ gxio_mpipe_equeue_put_at(equeue, edesc_head, slot);
+ slot++;
+
+ /* Egress the payload. */
+ while (p_used < p_len) {
+
+ /* Advance as needed. */
+ while (f_used >= f_size) {
+ f_id++;
+ f_size = sh->frags[f_id].size;
+ f_used = 0;
+ }
+
+ va = tile_net_frag_buf(&sh->frags[f_id]) + f_used;
+
+ /* Use bytes from the current fragment. */
+ n = p_len - p_used;
+ if (n > f_size - f_used)
+ n = f_size - f_used;
+ f_used += n;
+ p_used += n;
+
+ /* Egress a piece of the payload. */
+ edesc_body.va = va_to_tile_io_addr(va);
+ edesc_body.xfer_size = n;
+ edesc_body.bound = !(p_used < p_len);
+ gxio_mpipe_equeue_put_at(equeue, edesc_body, slot);
+ slot++;
+ }
+
+ tx_packets++;
+ tx_bytes += sh_len + p_len;
+
+ /* The last segment may be less than gso_size. */
+ data_len -= p_len;
+ if (data_len < p_len)
+ p_len = data_len;
+ }
+
+ /* Update stats. */
+ tile_net_stats_add(tx_packets, &priv->stats.tx_packets);
+ tile_net_stats_add(tx_bytes, &priv->stats.tx_bytes);
+}
+
+/* Do "TSO" handling for egress.
+ *
+ * Normally drivers set NETIF_F_TSO only to support hardware TSO;
+ * otherwise the stack uses scatter-gather to implement GSO in software.
+ * On our testing, enabling GSO support (via NETIF_F_SG) drops network
+ * performance down to around 7.5 Gbps on the 10G interfaces, although
+ * also dropping cpu utilization way down, to under 8%. But
+ * implementing "TSO" in the driver brings performance back up to line
+ * rate, while dropping cpu usage even further, to less than 4%. In
+ * practice, profiling of GSO shows that skb_segment() is what causes
+ * the performance overheads; we benefit in the driver from using
+ * preallocated memory to duplicate the TCP/IP headers.
+ */
+static int tile_net_tx_tso(struct sk_buff *skb, struct net_device *dev)
+{
+ struct tile_net_info *info = &__get_cpu_var(per_cpu_info);
+ struct tile_net_priv *priv = netdev_priv(dev);
+ int channel = priv->echannel;
+ struct tile_net_egress *egress = &egress_for_echannel[channel];
+ struct tile_net_comps *comps = info->comps_for_echannel[channel];
+ gxio_mpipe_equeue_t *equeue = egress->equeue;
+ unsigned long irqflags;
+ int num_edescs;
+ s64 slot;
+
+ /* Determine how many mpipe edesc's are needed. */
+ num_edescs = tso_count_edescs(skb);
+
+ local_irq_save(irqflags);
+
+ /* Try to acquire a completion entry and an egress slot. */
+ slot = tile_net_equeue_try_reserve(dev, comps, equeue, num_edescs);
+ if (slot < 0) {
+ local_irq_restore(irqflags);
+ return NETDEV_TX_BUSY;
+ }
+
+ /* Set up copies of header data properly. */
+ tso_headers_prepare(skb, egress->headers, slot);
+
+ /* Actually pass the data to the network hardware. */
+ tso_egress(dev, equeue, skb, egress->headers, slot);
+
+ /* Add a completion record. */
+ add_comp(equeue, comps, slot + num_edescs - 1, skb);
+
+ local_irq_restore(irqflags);
+
+ /* Make sure the egress timer is scheduled. */
+ tile_net_schedule_egress_timer();
+
+ return NETDEV_TX_OK;
+}
+
+/* Analyze the body and frags for a transmit request. */
+static unsigned int tile_net_tx_frags(struct frag *frags,
+ struct sk_buff *skb,
+ void *b_data, unsigned int b_len)
+{
+ unsigned int i, n = 0;
+
+ struct skb_shared_info *sh = skb_shinfo(skb);
+
+ if (b_len != 0) {
+ frags[n].buf = b_data;
+ frags[n++].length = b_len;
+ }
+
+ for (i = 0; i < sh->nr_frags; i++) {
+ skb_frag_t *f = &sh->frags[i];
+ frags[n].buf = tile_net_frag_buf(f);
+ frags[n++].length = skb_frag_size(f);
+ }
+
+ return n;
+}
+
+/* Help the kernel transmit a packet. */
+static int tile_net_tx(struct sk_buff *skb, struct net_device *dev)
+{
+ struct tile_net_info *info = &__get_cpu_var(per_cpu_info);
+ struct tile_net_priv *priv = netdev_priv(dev);
+ struct tile_net_egress *egress = &egress_for_echannel[priv->echannel];
+ gxio_mpipe_equeue_t *equeue = egress->equeue;
+ struct tile_net_comps *comps =
+ info->comps_for_echannel[priv->echannel];
+ unsigned int len = skb->len;
+ unsigned char *data = skb->data;
+ unsigned int num_edescs;
+ struct frag frags[MAX_FRAGS];
+ gxio_mpipe_edesc_t edescs[MAX_FRAGS];
+ unsigned long irqflags;
+ gxio_mpipe_edesc_t edesc = { { 0 } };
+ unsigned int i;
+ s64 slot;
+
+ if (skb_is_gso(skb))
+ return tile_net_tx_tso(skb, dev);
+
+ num_edescs = tile_net_tx_frags(frags, skb, data, skb_headlen(skb));
+
+ /* This is only used to specify the TLB. */
+ edesc.stack_idx = large_buffer_stack;
+
+ /* Prepare the edescs. */
+ for (i = 0; i < num_edescs; i++) {
+ edesc.xfer_size = frags[i].length;
+ edesc.va = va_to_tile_io_addr(frags[i].buf);
+ edescs[i] = edesc;
+ }
+
+ /* Mark the final edesc. */
+ edescs[num_edescs - 1].bound = 1;
+
+ /* Add checksum info to the initial edesc, if needed. */
+ if (skb->ip_summed == CHECKSUM_PARTIAL) {
+ unsigned int csum_start = skb_checksum_start_offset(skb);
+ edescs[0].csum = 1;
+ edescs[0].csum_start = csum_start;
+ edescs[0].csum_dest = csum_start + skb->csum_offset;
+ }
+
+ local_irq_save(irqflags);
+
+ /* Try to acquire a completion entry and an egress slot. */
+ slot = tile_net_equeue_try_reserve(dev, comps, equeue, num_edescs);
+ if (slot < 0) {
+ local_irq_restore(irqflags);
+ return NETDEV_TX_BUSY;
+ }
+
+ for (i = 0; i < num_edescs; i++)
+ gxio_mpipe_equeue_put_at(equeue, edescs[i], slot++);
+
+ /* Add a completion record. */
+ add_comp(equeue, comps, slot - 1, skb);
+
+ /* NOTE: Use ETH_ZLEN for short packets (e.g. 42 < 60). */
+ tile_net_stats_add(1, &priv->stats.tx_packets);
+ tile_net_stats_add(max_t(unsigned int, len, ETH_ZLEN),
+ &priv->stats.tx_bytes);
+
+ local_irq_restore(irqflags);
+
+ /* Make sure the egress timer is scheduled. */
+ tile_net_schedule_egress_timer();
+
+ return NETDEV_TX_OK;
+}
+
+/* Return subqueue id on this core (one per core). */
+static u16 tile_net_select_queue(struct net_device *dev, struct sk_buff *skb)
+{
+ return smp_processor_id();
+}
+
+/* Deal with a transmit timeout. */
+static void tile_net_tx_timeout(struct net_device *dev)
+{
+ int cpu;
+
+ for_each_online_cpu(cpu)
+ netif_wake_subqueue(dev, cpu);
+}
+
+/* Ioctl commands. */
+static int tile_net_ioctl(struct net_device *dev, struct ifreq *rq, int cmd)
+{
+ return -EOPNOTSUPP;
+}
+
+/* Get system network statistics for device. */
+static struct net_device_stats *tile_net_get_stats(struct net_device *dev)
+{
+ struct tile_net_priv *priv = netdev_priv(dev);
+ return &priv->stats;
+}
+
+/* Change the MTU. */
+static int tile_net_change_mtu(struct net_device *dev, int new_mtu)
+{
+ if ((new_mtu < 68) || (new_mtu > 1500))
+ return -EINVAL;
+ dev->mtu = new_mtu;
+ return 0;
+}
+
+/* Change the Ethernet address of the NIC.
+ *
+ * The hypervisor driver does not support changing MAC address. However,
+ * the hardware does not do anything with the MAC address, so the address
+ * which gets used on outgoing packets, and which is accepted on incoming
+ * packets, is completely up to us.
+ *
+ * Returns 0 on success, negative on failure.
+ */
+static int tile_net_set_mac_address(struct net_device *dev, void *p)
+{
+ struct sockaddr *addr = p;
+
+ if (!is_valid_ether_addr(addr->sa_data))
+ return -EINVAL;
+ memcpy(dev->dev_addr, addr->sa_data, dev->addr_len);
+ return 0;
+}
+
+#ifdef CONFIG_NET_POLL_CONTROLLER
+/* Polling 'interrupt' - used by things like netconsole to send skbs
+ * without having to re-enable interrupts. It's not called while
+ * the interrupt routine is executing.
+ */
+static void tile_net_netpoll(struct net_device *dev)
+{
+ disable_percpu_irq(ingress_irq);
+ tile_net_handle_ingress_irq(ingress_irq, NULL);
+ enable_percpu_irq(ingress_irq, 0);
+}
+#endif
+
+static const struct net_device_ops tile_net_ops = {
+ .ndo_open = tile_net_open,
+ .ndo_stop = tile_net_stop,
+ .ndo_start_xmit = tile_net_tx,
+ .ndo_select_queue = tile_net_select_queue,
+ .ndo_do_ioctl = tile_net_ioctl,
+ .ndo_get_stats = tile_net_get_stats,
+ .ndo_change_mtu = tile_net_change_mtu,
+ .ndo_tx_timeout = tile_net_tx_timeout,
+ .ndo_set_mac_address = tile_net_set_mac_address,
+#ifdef CONFIG_NET_POLL_CONTROLLER
+ .ndo_poll_controller = tile_net_netpoll,
+#endif
+};
+
+/* The setup function.
+ *
+ * This uses ether_setup() to assign various fields in dev, including
+ * setting IFF_BROADCAST and IFF_MULTICAST, then sets some extra fields.
+ */
+static void tile_net_setup(struct net_device *dev)
+{
+ ether_setup(dev);
+ dev->netdev_ops = &tile_net_ops;
+ dev->watchdog_timeo = TILE_NET_TIMEOUT;
+ dev->features |= NETIF_F_LLTX;
+ dev->features |= NETIF_F_HW_CSUM;
+ dev->features |= NETIF_F_SG;
+ dev->features |= NETIF_F_TSO;
+ dev->mtu = 1500;
+}
+
+/* Allocate the device structure, register the device, and obtain the
+ * MAC address from the hypervisor.
+ */
+static void tile_net_dev_init(const char *name, const uint8_t *mac)
+{
+ int ret;
+ int i;
+ int nz_addr = 0;
+ struct net_device *dev;
+ struct tile_net_priv *priv;
+
+ /* HACK: Ignore "loop" links. */
+ if (strncmp(name, "loop", 4) == 0)
+ return;
+
+ /* Allocate the device structure. Normally, "name" is a
+ * template, instantiated by register_netdev(), but not for us.
+ */
+ dev = alloc_netdev_mqs(sizeof(*priv), name, tile_net_setup,
+ NR_CPUS, 1);
+ if (!dev) {
+ pr_err("alloc_netdev_mqs(%s) failed\n", name);
+ return;
+ }
+
+ /* Initialize "priv". */
+ priv = netdev_priv(dev);
+ memset(priv, 0, sizeof(*priv));
+ priv->dev = dev;
+ priv->channel = -1;
+ priv->loopify_channel = -1;
+ priv->echannel = -1;
+
+ /* Get the MAC address and set it in the device struct; this must
+ * be done before the device is opened. If the MAC is all zeroes,
+ * we use a random address, since we're probably on the simulator.
+ */
+ for (i = 0; i < 6; i++)
+ nz_addr |= mac[i];
+
+ if (nz_addr) {
+ memcpy(dev->dev_addr, mac, 6);
+ dev->addr_len = 6;
+ } else {
+ random_ether_addr(dev->dev_addr);
+ }
+
+ /* Register the network device. */
+ ret = register_netdev(dev);
+ if (ret) {
+ netdev_err(dev, "register_netdev failed %d\n", ret);
+ free_netdev(dev);
+ return;
+ }
+}
+
+/* Per-cpu module initialization. */
+static void tile_net_init_module_percpu(void *unused)
+{
+ struct tile_net_info *info = &__get_cpu_var(per_cpu_info);
+ int my_cpu = smp_processor_id();
+
+ info->has_iqueue = false;
+
+ info->my_cpu = my_cpu;
+
+ /* Initialize the egress timer. */
+ hrtimer_init(&info->egress_timer, CLOCK_MONOTONIC, HRTIMER_MODE_REL);
+ info->egress_timer.function = tile_net_handle_egress_timer;
+}
+
+/* Module initialization. */
+static int __init tile_net_init_module(void)
+{
+ int i;
+ char name[GXIO_MPIPE_LINK_NAME_LEN];
+ uint8_t mac[6];
+
+ pr_info("Tilera Network Driver\n");
+
+ mutex_init(&tile_net_devs_for_channel_mutex);
+
+ /* Initialize each CPU. */
+ on_each_cpu(tile_net_init_module_percpu, NULL, 1);
+
+ /* Find out what devices we have, and initialize them. */
+ for (i = 0; gxio_mpipe_link_enumerate_mac(i, name, mac) >= 0; i++)
+ tile_net_dev_init(name, mac);
+
+ if (!network_cpus_init())
+ network_cpus_map = *cpu_online_mask;
+
+ return 0;
+}
+
+module_init(tile_net_init_module);
--
1.6.5.2
^ permalink raw reply related
* Re: [PATCH v17 08/15] seccomp: add system call filtering using BPF
From: Kees Cook @ 2012-04-06 20:44 UTC (permalink / raw)
To: Andrew Morton
Cc: Will Drewry, linux-kernel, linux-security-module, linux-arch,
linux-doc, kernel-hardening, netdev, x86, arnd, davem, hpa, mingo,
oleg, peterz, rdunlap, mcgrathr, tglx, luto, eparis, serge.hallyn,
djm, scarybeasts, indan, pmoore, corbet, eric.dumazet, markus,
coreyb, jmorris
In-Reply-To: <20120406132330.457a05cf.akpm@linux-foundation.org>
On Fri, Apr 6, 2012 at 1:23 PM, Andrew Morton <akpm@linux-foundation.org> wrote:
> On Thu, 29 Mar 2012 15:01:53 -0500
> Will Drewry <wad@chromium.org> wrote:
>
>> [This patch depends on luto@mit.edu's no_new_privs patch:
>> https://lkml.org/lkml/2012/1/30/264
>> included in this series for ease of consumption.
>> ]
>>
>> This patch adds support for seccomp mode 2. Mode 2 introduces the
>> ability for unprivileged processes to install system call filtering
>> policy expressed in terms of a Berkeley Packet Filter (BPF) program.
>> This program will be evaluated in the kernel for each system call
>> the task makes and computes a result based on data in the format
>> of struct seccomp_data.
>> ...
>> +static void seccomp_filter_log_failure(int syscall)
>> +{
>> + int compat = 0;
>> +#ifdef CONFIG_COMPAT
>> + compat = is_compat_task();
>> +#endif
>
> hm, I'm surprised that we don't have a zero-returning implementation of
> is_compat_task() when CONFIG_COMPAT=n. Seems silly. Blames Arnd.
There is, but this chunk of the patch is removed later on in the
series. We could just drop seccomp_filter_log_failure and it's single
call entirely and depend on the later enhancement to add the logging
that is desired.
>> +static long seccomp_attach_filter(struct sock_fprog *fprog)
>> +{
>> + struct seccomp_filter *filter;
>> + unsigned long fp_size = fprog->len * sizeof(struct sock_filter);
>> + unsigned long total_insns = fprog->len;
>> + long ret;
>> +
>> + if (fprog->len == 0 || fprog->len > BPF_MAXINSNS)
>> + return -EINVAL;
>> +
>> + for (filter = current->seccomp.filter; filter; filter = filter->prev)
>> + total_insns += filter->len + 4; /* include a 4 instr penalty */
>
> So tasks don't share filters? We copy them by value at fork? Do we do
> this at vfork() too?
The filter chain is shared (and refcounted).
>> + if (total_insns > MAX_INSNS_PER_PATH)
>> + return -ENOMEM;
>> +
>> + /*
>> + * Installing a seccomp filter requires that the task have
>> + * CAP_SYS_ADMIN in its namespace or be running with no_new_privs.
>> + * This avoids scenarios where unprivileged tasks can affect the
>> + * behavior of privileged children.
>> + */
>> + if (!current->no_new_privs &&
>> + security_capable_noaudit(current_cred(), current_user_ns(),
>> + CAP_SYS_ADMIN) != 0)
>> + return -EACCES;
>> +
>> + /* Allocate a new seccomp_filter */
>> + filter = kzalloc(sizeof(struct seccomp_filter) + fp_size, GFP_KERNEL);
>
> I think this gives userspace an easy way of causing page allocation
> failure warnings, by permitting large kmalloc() attempts. Add
> __GFP_NOWARN?
This is likely mitigated by the MAX_INSNS_PER_PATH check above, but,
yeah, there's no harm in adding __GFP_NOWARN.
>> +/* put_seccomp_filter - decrements the ref count of tsk->seccomp.filter */
>> +void put_seccomp_filter(struct task_struct *tsk)
>> +{
>> + struct seccomp_filter *orig = tsk->seccomp.filter;
>> + /* Clean up single-reference branches iteratively. */
>> + while (orig && atomic_dec_and_test(&orig->usage)) {
>> + struct seccomp_filter *freeme = orig;
>> + orig = orig->prev;
>> + kfree(freeme);
>> + }
>> +}
>
> So if one of the filters in the list has an elevated refcount, we bail
> out on the remainder of the list. Seems odd.
This so that every filter in the list doesn't need to have their
refcount raised. As long as the counting up matching the counting
down, it's fine. This allows for process trees branching the filter
list at different times still being safe. IIUC, this code was based on
how namespace refcounting is handled. I spent some time proving to
myself that it was correctly refcounted a while back. More eyes is
better, of course. :)
-Kees
--
Kees Cook
ChromeOS Security
^ permalink raw reply
* Re: [PATCH v17 01/15] Add PR_{GET,SET}_NO_NEW_PRIVS to prevent execve from granting privs
From: Markus Gutschke @ 2012-04-06 20:47 UTC (permalink / raw)
To: Andrew Morton
Cc: Will Drewry, linux-kernel, linux-security-module, linux-arch,
linux-doc, kernel-hardening, netdev, x86, arnd, davem, hpa, mingo,
oleg, peterz, rdunlap, mcgrathr, tglx, luto, eparis, serge.hallyn,
djm, scarybeasts, indan, pmoore, corbet, eric.dumazet, coreyb,
keescook, jmorris, Andy Lutomirski
In-Reply-To: <20120406124921.5754e941.akpm@linux-foundation.org>
On Fri, Apr 6, 2012 at 12:49, Andrew Morton <akpm@linux-foundation.org> wrote:
> On Thu, 29 Mar 2012 15:01:46 -0500
> Will Drewry <wad@chromium.org> wrote:
>> From: Andy Lutomirski <luto@amacapital.net>
>> With this set, a lot of dangerous operations (chroot, unshare, etc)
>> become a lot less dangerous because there is no possibility of
>> subverting privileged binaries.
I don't want to derail things. So, tell me to go away, if I can't have
what I want.
Having said that, it would be great if NO_NEW_PRIVS also gave access
to the restricted clone() flags. Such as CLONE_NEWIPC, CLONE_NEWNET
and CLONE_NEWPID.
Markus
^ permalink raw reply
* Re: [PATCH v17 01/15] Add PR_{GET,SET}_NO_NEW_PRIVS to prevent execve from granting privs
From: Andrew Lutomirski @ 2012-04-06 20:54 UTC (permalink / raw)
To: Markus Gutschke
Cc: Andrew Morton, Will Drewry, linux-kernel, linux-security-module,
linux-arch, linux-doc, kernel-hardening, netdev, x86, arnd, davem,
hpa, mingo, oleg, peterz, rdunlap, mcgrathr, tglx, eparis,
serge.hallyn, djm, scarybeasts, indan, pmoore, corbet,
eric.dumazet, coreyb, keescook, jmorris, Andy Lutomirski
In-Reply-To: <CAE6n16m3v4BghY7GGwHCy2t-7-vmRpyOV6swap9GrMQnmGLroA@mail.gmail.com>
On Fri, Apr 6, 2012 at 1:47 PM, Markus Gutschke <markus@chromium.org> wrote:
> On Fri, Apr 6, 2012 at 12:49, Andrew Morton <akpm@linux-foundation.org> wrote:
>> On Thu, 29 Mar 2012 15:01:46 -0500
>> Will Drewry <wad@chromium.org> wrote:
>>> From: Andy Lutomirski <luto@amacapital.net>
>>> With this set, a lot of dangerous operations (chroot, unshare, etc)
>>> become a lot less dangerous because there is no possibility of
>>> subverting privileged binaries.
>
> I don't want to derail things. So, tell me to go away, if I can't have
> what I want.
>
> Having said that, it would be great if NO_NEW_PRIVS also gave access
> to the restricted clone() flags. Such as CLONE_NEWIPC, CLONE_NEWNET
> and CLONE_NEWPID.
I decided to hold off on extra controversy for awhile. However:
https://git.kernel.org/?p=linux/kernel/git/luto/linux.git;a=commit;h=9a520b74ad5dc14a3d6950b6d63a64714adbdd7d
and
http://web.mit.edu/luto/www/linux/nnp/newns.c
I fully intend to resurrect both of those once nnp lands.
(FWIW, I think that CLONE_NEWPID interacts badly with unix socket
credentials and should be fixed as a prerequisite for making it easier
to access.)
--Andy
^ permalink raw reply
* Re: [PATCH v17 01/15] Add PR_{GET,SET}_NO_NEW_PRIVS to prevent execve from granting privs
From: Markus Gutschke @ 2012-04-06 21:04 UTC (permalink / raw)
To: Andrew Lutomirski
Cc: Andrew Morton, Will Drewry, linux-kernel, linux-security-module,
linux-arch, linux-doc, kernel-hardening, netdev, x86, arnd, davem,
hpa, mingo, oleg, peterz, rdunlap, mcgrathr, tglx, eparis,
serge.hallyn, djm, scarybeasts, indan, pmoore, corbet,
eric.dumazet, coreyb, keescook, jmorris, Andy Lutomirski
In-Reply-To: <CAObL_7GzsJ+EW94oYG+EzcRqYyH2EPTyFgTgo6zmSz1yxEe-xw@mail.gmail.com>
On Fri, Apr 6, 2012 at 13:54, Andrew Lutomirski <luto@mit.edu> wrote:
> (FWIW, I think that CLONE_NEWPID interacts badly with unix socket
> credentials and should be fixed as a prerequisite for making it easier
> to access.)
sendmsg() is a big hair ball. And yes, I have all sorts of things on
my wish list that touch sendmsg(). I don't think, I'll get them
fullfilled anytime soon, though:
- sendmsg() does lots of different things: sending on unconnected
sockets, sending file descriptors, sending unix decriptors, and
plain-old sending data. These operations have very different security
properties and implications. It would be awesome if BPF filters could
filter these different types of operations selectively.
- ancillary data is a cool concept in general. We should use it more.
If I could send a memory mapping from one process to another, that
would solve so many problems. But I know, I am dreaming; I don't
expect to see this feature any time soon.
Markus
^ permalink raw reply
* Re: [PATCH v17 08/15] seccomp: add system call filtering using BPF
From: Andrew Morton @ 2012-04-06 21:05 UTC (permalink / raw)
To: Kees Cook
Cc: Will Drewry, linux-kernel, linux-security-module, linux-arch,
linux-doc, kernel-hardening, netdev, x86, arnd, davem, hpa, mingo,
oleg, peterz, rdunlap, mcgrathr, tglx, luto, eparis, serge.hallyn,
djm, scarybeasts, indan, pmoore, corbet, eric.dumazet, markus,
coreyb, jmorris
In-Reply-To: <CAGXu5jJVDLzCOyCo-q6+pF-_3v4Ws8jBzYXwac419uv2QQS0mA@mail.gmail.com>
On Fri, 6 Apr 2012 13:44:43 -0700
Kees Cook <keescook@chromium.org> wrote:
> On Fri, Apr 6, 2012 at 1:23 PM, Andrew Morton <akpm@linux-foundation.org> wrote:
> > On Thu, 29 Mar 2012 15:01:53 -0500
> > Will Drewry <wad@chromium.org> wrote:
> >
> >> [This patch depends on luto@mit.edu's no_new_privs patch:
> >> https://lkml.org/lkml/2012/1/30/264
> >> included in this series for ease of consumption.
> >> ]
> >>
> >> This patch adds support for seccomp mode 2. Mode 2 introduces the
> >> ability for unprivileged processes to install system call filtering
> >> policy expressed in terms of a Berkeley Packet Filter (BPF) program.
> >> This program will be evaluated in the kernel for each system call
> >> the task makes and computes a result based on data in the format
> >> of struct seccomp_data.
> >> ...
> >> +static void seccomp_filter_log_failure(int syscall)
> >> +{
> >> + int compat = 0;
> >> +#ifdef CONFIG_COMPAT
> >> + compat = is_compat_task();
> >> +#endif
> >
> > hm, I'm surprised that we don't have a zero-returning implementation of
> > is_compat_task() when CONFIG_COMPAT=n. Seems silly. Blames Arnd.
>
> There is
I can't find it. The definition in include/linux/compat.h is inside
#ifdef CONFIG_COMPAT.
> >> +static long seccomp_attach_filter(struct sock_fprog *fprog)
> >> +{
> >> + struct seccomp_filter *filter;
> >> + unsigned long fp_size = fprog->len * sizeof(struct sock_filter);
> >> + unsigned long total_insns = fprog->len;
> >> + long ret;
> >> +
> >> + if (fprog->len == 0 || fprog->len > BPF_MAXINSNS)
> >> + return -EINVAL;
> >> +
> >> + for (filter = current->seccomp.filter; filter; filter = filter->prev)
> >> + total_insns += filter->len + 4; /* include a 4 instr penalty */
> >
> > So tasks don't share filters? We copy them by value at fork? Do we do
> > this at vfork() too?
>
> The filter chain is shared (and refcounted).
So what's the locking rule for accessing and modifying that
singly-linked list?
> ...
> >> +/* put_seccomp_filter - decrements the ref count of tsk->seccomp.filter */
> >> +void put_seccomp_filter(struct task_struct *tsk)
> >> +{
> >> + struct seccomp_filter *orig = tsk->seccomp.filter;
> >> + /* Clean up single-reference branches iteratively. */
> >> + while (orig && atomic_dec_and_test(&orig->usage)) {
> >> + struct seccomp_filter *freeme = orig;
> >> + orig = orig->prev;
> >> + kfree(freeme);
> >> + }
> >> +}
> >
> > So if one of the filters in the list has an elevated refcount, we bail
> > out on the remainder of the list. Seems odd.
>
> This so that every filter in the list doesn't need to have their
> refcount raised. As long as the counting up matching the counting
> down, it's fine. This allows for process trees branching the filter
> list at different times still being safe. IIUC, this code was based on
> how namespace refcounting is handled. I spent some time proving to
> myself that it was correctly refcounted a while back. More eyes is
> better, of course. :)
Please ensure that future readers of this code have a description of
how it is supposed to work.
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