We need to use dma_mapping_error() to check the dma address returned
by dma_map_single/page(). Otherwise we would get warning like this:
WARNING: at lib/dma-debug.c:1140
Modules linked in:
CPU: 0 PID: 0 Comm: swapper/0 Not tainted 3.18.0-rc2-next-20141029 #196
task: c0834300 ti: effe6000 task.ti: c0874000
NIP: c02b2c98 LR: c02b2c98 CTR: c030abc4
REGS: effe7d70 TRAP: 0700 Not tainted (3.18.0-rc2-next-20141029)
MSR: 00021000 <CE,ME> CR: 22044022 XER: 20000000
GPR00: c02b2c98 effe7e20 c0834300 00000098 00021000 00000000 c030b898 00000003
GPR08: 00000001 00000000 00000001 749eec9d 22044022 1001abe0 00000020 ef278678
GPR16: ef278670 ef278668 ef278660 070a8040 c087f99c c08cdc60 00029000 c0840d44
GPR24: c08be6e8 c0840000 effe7e78 ef041340 00000600 ef114e10 00000000 c08be6e0
NIP [c02b2c98] check_unmap+0x51c/0x9e4
LR [c02b2c98] check_unmap+0x51c/0x9e4
Call Trace:
[effe7e20] [c02b2c98] check_unmap+0x51c/0x9e4 (unreliable)
[effe7e70] [c02b31d8] debug_dma_unmap_page+0x78/0x8c
[effe7ed0] [c03d1640] gfar_clean_rx_ring+0x208/0x488
[effe7f40] [c03d1a9c] gfar_poll_rx_sq+0x3c/0xa8
[effe7f60] [c04f8714] net_rx_action+0xc0/0x178
[effe7f90] [c00435a0] __do_softirq+0x100/0x1fc
[effe7fe0] [c0043958] irq_exit+0xa4/0xc8
[effe7ff0] [c000d14c] call_do_irq+0x24/0x3c
[c0875e90] [c00048a0] do_IRQ+0x8c/0xf8
[c0875eb0] [c000ed10] ret_from_except+0x0/0x18
For TX, we need to unmap the pages which has already been mapped and
free the skb before return.
For RX, move the dma mapping and error check to gfar_new_skb(). We
would reuse the original skb in the rx ring when either allocating
skb failure or dma mapping error.
Signed-off-by: Kevin Hao <haokexin@gmail.com>
Signed-off-by: Claudiu Manoil <claudiu.manoil@freescale.com>
Reviewed-by: Claudiu Manoil <claudiu.manoil@freescale.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
0a4b5a2488