EDK2 PXE driver creates two child devices - IPv4 and IPv6 - with
bound SNP instance. This means we get three cards for every physical
adapter when enumerating. Not only is this confusing, this may result
in grub ignoring packets that come in via the "wrong" card.
Example of device hierarchy is
Ctrl[91] PciRoot(0x0)/Pci(0x3,0x0)
Ctrl[95] PciRoot(0x0)/Pci(0x3,0x0)/MAC(525400123456,0x1)
Ctrl[B4] PciRoot(0x0)/Pci(0x3,0x0)/MAC(525400123456,0x1)/IPv4(0.0.0.0)
Ctrl[BC] PciRoot(0x0)/Pci(0x3,0x0)/MAC(525400123456,0x1)/IPv6(0000:0000:0000:0000:0000:0000:0000:0000)
Skip PXE created virtual devices when enumerating cards. Make sure to
find real card when applying initial autoconfiguration during PXE boot,
this information is associated with one of child devices.
This reverts commits 47b2bee3ef
and 8d3c4544ff. It is not safe
to free allocated cards, dangling pointers main remain. Such
cleanup requires more changes in net core.
* include/grub/ieee1275/ieee1275.h (grub_ieee1275_flag): New enum values
GRUB_IEEE1275_FLAG_NO_OFNET_SUFFIX and
GRUB_IEEE1275_FLAG_VIRT_TO_REAL_BROKEN.
* grub-core/net/drivers/efi/efinet.c (grub_efinet_findcards): Use
txbufsize.
* grub-core/kern/ieee1275/cmain.c (grub_ieee1275_find_options): Use
compatible property to check for macs. Set
GRUB_IEEE1275_FLAG_NO_OFNET_SUFFIX and
GRUB_IEEE1275_FLAG_VIRT_TO_REAL_BROKEN on macs.
* grub-core/net/drivers/ieee1275/ofnet.c (card_open): Don't add suffix
if GRUB_IEEE1275_FLAG_NO_OFNET_SUFFIX is set.
(send_card_buffer): Use txbuf.
(grub_ofnet_findcards): Allocate txbuf. Simplify code flow and move
nested function out of the parent while on it.
* include/grub/net.h (grub_net_card_driver): Allow driver to modify
card. All users updated.
(grub_net_card): New members txbuf, rcvbuf, rcvbufsize and txbusy.
* grub-core/net/drivers/efi/efinet.c (send_card_buffer): Reuse buffer.
(get_card_packet): Likewise.
(grub_efinet_findcards): Init new fields.
