Commit Graph

7 Commits

Author SHA1 Message Date
Philippe Mathieu-Daudé b8c4b67e3e hw/net: Make NetCanReceive() return a boolean
The NetCanReceive handler return whether the device can or
can not receive new packets. Make it obvious by returning
a boolean type.

Signed-off-by: Philippe Mathieu-Daudé <philmd@redhat.com>
Acked-by: David Gibson <david@gibson.dropbear.id.au>
Reviewed-by: Alistair Francis <alistair.francis@wdc.com>
Reviewed-by: Cédric Le Goater <clg@kaod.org>
Signed-off-by: Jason Wang <jasowang@redhat.com>
2020-03-31 21:14:35 +08:00
Peter Maydell a43790f2f6 hw/net/i82596.c: Avoid reading off end of buffer in i82596_receive()
The i82596_receive() function attempts to pass the guest a buffer
which is effectively the concatenation of the data it is passed and a
4 byte CRC value.  However, rather than implementing this as "write
the data; then write the CRC" it instead bumps the length value of
the data by 4, and writes 4 extra bytes from beyond the end of the
buffer, which it then overwrites with the CRC.  It also assumed that
we could always fit all four bytes of the CRC into the final receive
buffer, which might not be true if the CRC needs to be split over two
receive buffers.

Calculate separately how many bytes we need to transfer into the
guest's receive buffer from the source buffer, and how many we need
to transfer from the CRC work.

We add a count 'bufsz' of the number of bytes left in the source
buffer, which we use purely to assert() that we don't overrun.

Spotted by Coverity (CID 1419396) for the specific case when we end
up using a local array as the source buffer.

Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Signed-off-by: Jason Wang <jasowang@redhat.com>
2020-03-31 21:14:35 +08:00
Philippe Mathieu-Daudé baba731bc6 hw/net/i82596: Correct command bitmask (CID 1419392)
The command is 32-bit, but we are loading the 16 upper bits with
the 'get_uint16(s->scb + 2)' call.

Once shifted by 16, the command bits match the status bits:

- Command
  Bit 31 ACK-CX   Acknowledges that the CU completed an Action Command.
  Bit 30 ACK-FR   Acknowledges that the RU received a frame.
  Bit 29 ACK-CNA  Acknowledges that the Command Unit became not active.
  Bit 28 ACK-RNR  Acknowledges that the Receive Unit became not ready.

- Status
  Bit 15 CX       The CU finished executing a command with its I(interrupt) bit set.
  Bit 14 FR       The RU finished receiving a frame.
  Bit 13 CNA      The Command Unit left the Active state.
  Bit 12 RNR      The Receive Unit left the Ready state.

Add the SCB_COMMAND_ACK_MASK definition to simplify the code.

This fixes Coverity 1419392 (CONSTANT_EXPRESSION_RESULT):

  /hw/net/i82596.c: 352 in examine_scb()
  346         cuc = (command >> 8) & 0x7;
  347         ruc = (command >> 4) & 0x7;
  348         DBG(printf("MAIN COMMAND %04x  cuc %02x ruc %02x\n", command, cuc, ruc));
  349         /* and clear the scb command word */
  350         set_uint16(s->scb + 2, 0);
  351
  >>>     CID 1419392:    (CONSTANT_EXPRESSION_RESULT)
  >>>     "command & (2147483648UL /* 1UL << 31 */)" is always 0 regardless of the values of its operands. This occurs as the logical operand of "if".
  352         if (command & BIT(31))      /* ACK-CX */
  353             s->scb_status &= ~SCB_STATUS_CX;
  >>>     CID 1419392:    (CONSTANT_EXPRESSION_RESULT)
  >>>     "command & (1073741824UL /* 1UL << 30 */)" is always 0 regardless of the values of its operands. This occurs as the logical operand of "if".
  354         if (command & BIT(30))      /*ACK-FR */
  355             s->scb_status &= ~SCB_STATUS_FR;
  >>>     CID 1419392:    (CONSTANT_EXPRESSION_RESULT)
  >>>     "command & (536870912UL /* 1UL << 29 */)" is always 0 regardless of the values of its operands. This occurs as the logical operand of "if".
  356         if (command & BIT(29))      /*ACK-CNA */
  357             s->scb_status &= ~SCB_STATUS_CNA;
  >>>     CID 1419392:    (CONSTANT_EXPRESSION_RESULT)
  >>>     "command & (268435456UL /* 1UL << 28 */)" is always 0 regardless of the values of its operands. This occurs as the logical operand of "if".
  358         if (command & BIT(28))      /*ACK-RNR */
  359             s->scb_status &= ~SCB_STATUS_RNR;

Fixes: Covertiy CID 1419392 (commit 376b851909)
Signed-off-by: Philippe Mathieu-Daudé <f4bug@amsat.org>
Reviewed-by: Peter Maydell <peter.maydell@linaro.org>
Signed-off-by: Jason Wang <jasowang@redhat.com>
2020-03-31 21:14:35 +08:00
Peter Maydell 19f7034773 Avoid address_space_rw() with a constant is_write argument
The address_space_rw() function allows either reads or writes
depending on the is_write argument passed to it; this is useful
when the direction of the access is determined programmatically
(as for instance when handling the KVM_EXIT_MMIO exit reason).
Under the hood it just calls either address_space_write() or
address_space_read_full().

We also use it a lot with a constant is_write argument, though,
which has two issues:
 * when reading "address_space_rw(..., 1)" this is less
   immediately clear to the reader as being a write than
   "address_space_write(...)"
 * calling address_space_rw() bypasses the optimization
   in address_space_read() that fast-paths reads of a
   fixed length

This commit was produced with the included Coccinelle script
scripts/coccinelle/exec_rw_const.cocci.

Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Reviewed-by: Philippe Mathieu-Daudé <philmd@redhat.com>
Reviewed-by: Edgar E. Iglesias <edgar.iglesias@xilinx.com>
Reviewed-by: Laurent Vivier <lvivier@redhat.com>
Reviewed-by: Cédric Le Goater <clg@kaod.org>
Acked-by: Christian Borntraeger <borntraeger@de.ibm.com>
Reviewed-by: Cornelia Huck <cohuck@redhat.com>
Reviewed-by: Alistair Francis <alistair.francis@wdc.com>
Acked-by: David Gibson <david@gibson.dropbear.id.au>
Message-Id: <20200218112457.22712-1-peter.maydell@linaro.org>
[PMD: Update macvm_set_cr0() reported by Laurent Vivier]
Signed-off-by: Philippe Mathieu-Daudé <philmd@redhat.com>
2020-02-20 14:47:08 +01:00
Philippe Mathieu-Daudé 1ccda935d4 Let address_space_rw() calls pass a boolean 'is_write' argument
Since its introduction in commit ac1970fbe8, address_space_rw()
takes a boolean 'is_write' argument. Fix the codebase by using
an explicit boolean type.

This commit was produced with the included Coccinelle script
scripts/coccinelle/exec_rw_const.

Inspired-by: Peter Maydell <peter.maydell@linaro.org>
Signed-off-by: Philippe Mathieu-Daudé <philmd@redhat.com>
2020-02-20 14:47:08 +01:00
Philippe Mathieu-Daudé 4ef044cb14 hw/net: Avoid casting non-const pointer, use address_space_write()
The NetReceive prototype gets a const buffer:

  typedef ssize_t (NetReceive)(NetClientState *, const uint8_t *, size_t);

We already have the address_space_write() method to write a const
buffer to an address space. Use it to avoid:

  hw/net/i82596.c: In function ‘i82596_receive’:
  hw/net/i82596.c:644:54: error: passing argument 4 of ‘address_space_rw’ discards ‘const’ qualifier from pointer target type [-Werror=discarded-qualifiers]

This commit was produced with the included Coccinelle script
scripts/coccinelle/exec_rw_const.

Signed-off-by: Philippe Mathieu-Daudé <philmd@redhat.com>
2020-02-20 14:47:08 +01:00
Helge Deller 376b851909 hppa: Add support for LASI chip with i82596 NIC
LASI is a built-in multi-I/O chip which supports serial, parallel,
network (Intel i82596 Apricot), sound and other functionalities.
LASI has been used in many HP PARISC machines.
This patch adds the necessary parts to allow Linux and HP-UX to detect
LASI and the network card.

Signed-off-by: Helge Deller <deller@gmx.de>
Signed-off-by: Sven Schnelle <svens@stackframe.org>
Message-Id: <20191220211512.3289-3-svens@stackframe.org>
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
2020-01-27 10:49:51 -08:00