Make a pass over skbuff.h:
- implement some missing bits,
- sprinkle some const,
- add locking and read/write_once calls as needed to provide
synchronization as expected by Linux,
- fix some typos,
- remove return from void functions,
- adjust tracing macros.
Sponsored by: The FreeBSD Foundation
MFC after: 3 days
PR: 283903 (rtw88 skb leak)
Tested by: Guillaume Outters (guillaume-freebsd outters.eu)
Differential Revision: https://reviews.freebsd.org/D49101
- skb_reset_tail_pointer(): we do not do offsets so do a plain reset
- skb_add_rx_frag(): adjust data_len to keep track of the frag
- based on that implement skb_is_nonlinear() and skb_linearize()
- implement build_skb() and adjust linuxkpi_kfree_skb() and ddb macro.
Sponsored by: The FreeBSD Foundation (partially)
MFC after: 3 days
While working on new and updates to drivers more skbuff changes
came up. Sort out the list/prev/next header problem and add more
(so far dummy) functions needed.
MFC after: 1 week
Some drivers, such as Realtek's rtw88, require 32bit DMA in
a single segment. busdma(9) has a hard time providing this
currently for 3-ish pages at large quantities
(see lkpi_pci_nseg1_fail in linux_pci.c e86707418c).
Work around this for now by allowing a tunable to enforce
physical addresses allocation limits on 64bit platforms (ignoring PAE)
using "old-school" contigmalloc(9) to avoid bouncing.
A patch needing a custom kernel compiled was tested in the last weeks
by rtw88 users providing the 32bit limit only hardcoded. The 36bit
limit can be found in iwlwifi so is added as a testing option along.
This is put in as a bandaid for now, so people no longer need to patch
and compile their own kernels to use rtw88 and to allow us to MFC the
driver as well before the amounts of commits to track increases by
much more.
Sponsored by: The FreeBSD Foundation
MFC after: 3 days
Implement skb_copy() with omissions of fragments and possibly other fields
for now. Should we hit frags at any point a log message will let us know.
For the few cases we need this currently this is enough.
Sponsored by: The FreeBSD Foundation
MFC after: 3 days
dev_alloc_skb() comapred to alloc_skb() reserves some headroom
at the beginning of the skb which is used by drivers.
Split the code for the two cases and reserve NET_SKB_PAD space,
which should at least be 32 octets.
Sponsored by: The FreeBSD Foundation
MFC after: 3 days
In skb_queue_splice_init() we set a next value and then used that new
value to further update the remaining linking rather than the original
value. Introduce another temporary variable 'n' to hold the original
value and use that.
While here rename q and h to from and to as otherwise it was too
confusing to read.
Also initialize skb->prev and skb->next to point to skb itself if
for nothing else at least to aid debugging.
Reported by: phk (panic in iwl_txq_reclaim)
Sponsored by: The FreeBSD Foundation
MFC after: 3 days
Various updates to skbuff for new/updated drivers and some housekeeping:
- update types and struct members, add new (stub) functions
- improve freeing of frags.
- fix an issue with sleeping during alloc for dev_alloc_skb().
- Adjust a KASSERT for skb_reserve() which apparently can be called
multiple times if no data was put into the skb yet.
- move the sysctl from linux_8022.c (which may be in a different module)
to linux_skbuff.c so in case we turn debugging on we do not run into
unresolved symbols. Rename the sysctl variable to be less conflicting
and update debugging macros along with that; also add IMPROVE().
- add DDB support to show an skbuff.
- adjust comments/whitespace.
No functional changes intended for iwlwifi.
Sponsored by: The FreeBSD Foundation (partially)
MFC after: 3 days
This is a work-in-progress implementation of sk_buff compat code
used for wireless drivers only currently.
Bring in this version of the code as it has proven to be good enough
to have packets going for a few months.
The current implementation has several drawbacks including the need
for us to copy data between sk_buffs and mbufs.
Do not rely on the internals of this implementation. They are highly
likely to change as we will improve the integration to FreeBSD mbufs.
Sponsored by: The FreeBSD Foundation
MFC after: 3 days
