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/*
 * netsniff-ng - the packet sniffing beast
 * Copyright 2009, 2010 Daniel Borkmann.
 * Subject to the GPL, version 2.
 */

#ifndef TX_RING_H
#define TX_RING_H

#include <stdbool.h>

#include "ring.h"
#include "built_in.h"

/* Give userland 10 us time to push packets to the ring */
#define TX_KERNEL_PULL_INT	10

extern void destroy_tx_ring(int sock, struct ring *ring);
extern void create_tx_ring(int sock, struct ring *ring, int verbose);
extern void mmap_tx_ring(int sock, struct ring *ring);
extern void alloc_tx_ring_frames(int sock, struct ring *ring);
extern void bind_tx_ring(int sock, struct ring *ring, int ifindex);
extern void setup_tx_ring_layout(int sock, struct ring *ring,
				 unsigned int size, bool jumbo_support);
extern void set_packet_loss_discard(int sock);

static inline int user_may_pull_from_tx(struct tpacket2_hdr *hdr)
{
	return !(hdr->tp_status & (TP_STATUS_SEND_REQUEST | TP_STATUS_SENDING));
}

static inline void kernel_may_pull_from_tx(struct tpacket2_hdr *hdr)
{
	hdr->tp_status = TP_STATUS_SEND_REQUEST;
}

static inline int pull_and_flush_tx_ring(int sock)
{
	return sendto(sock, NULL, 0, MSG_DONTWAIT, NULL, 0);
}

static inline int pull_and_flush_tx_ring_wait(int sock)
{
	return sendto(sock, NULL, 0, 0, NULL, 0);
}

#endif /* TX_RING_H */
MU in ExitBootServices(), after which unaligned accesses to RAM are no longer supported. Commit: abfb7b686a3e ("efi/libstub/arm*: Pass latest memory map to the kernel") fixed an issue in the memory map handling of the stub FDT code, but inadvertently created an issue with such firmware, by moving some of the FDT manipulation to after the invocation of ExitBootServices(). Given that the stub's libfdt implementation uses the ordinary, accelerated string functions, which rely on hardware handling of unaligned accesses, manipulating the FDT with the MMU off may result in alignment faults. So fix the situation by moving the update_fdt_memmap() call into the callback function invoked by efi_exit_boot_services() right before it calls the ExitBootServices() UEFI service (which is arguably a better place for it anyway) Note that disabling the MMU in ExitBootServices() is not compliant with the UEFI spec, and carries great risk due to the fact that switching from cached to uncached memory accesses halfway through compiler generated code (i.e., involving a stack) can never be done in a way that is architecturally safe. Fixes: abfb7b686a3e ("efi/libstub/arm*: Pass latest memory map to the kernel") Signed-off-by: Ard Biesheuvel <ard.biesheuvel@linaro.org> Tested-by: Riku Voipio <riku.voipio@linaro.org> Cc: <stable@vger.kernel.org> Cc: mark.rutland@arm.com Cc: linux-efi@vger.kernel.org Cc: matt@codeblueprint.co.uk Cc: leif.lindholm@linaro.org Cc: linux-arm-kernel@lists.infradead.org Link: http://lkml.kernel.org/r/1485971102-23330-2-git-send-email-ard.biesheuvel@linaro.org Signed-off-by: Ingo Molnar <mingo@kernel.org>
Diffstat (limited to 'Documentation')