src/sys/mips/include, branch main

mips: Remove sys/mips

2021-12-31T03:57:24Z

Remove sys/mips as the next step of decomissioning mips from the tree. Remove mips special cases from the kernel make files. Remove the mips specific linker scripts. Sponsored by: Netflix

Simplify swi for bus_dma.

2021-12-28T21:51:25Z

When a DMA request using bounce pages completes, a swi is triggered to schedule pending DMA requests using the just-freed bounce pages. For a long time this bus_dma swi has been tied to a "virtual memory" swi (swi_vm). However, all of the swi_vm implementations are the same and consist of checking a flag (busdma_swi_pending) which is always true and if set calling busdma_swi. I suspect this dates back to the pre-SMPng days and that the intention was for swi_vm to serve as a mux. However, in the current scheme there's no need for the mux. Instead, remove swi_vm and vm_ih. Each bus_dma implementation that uses bounce pages is responsible for creating its own swi (busdma_ih) which it now schedules directly. This swi invokes busdma_swi directly removing the need for busdma_swi_pending. One consequence is that the swi now works on RISC-V which had previously failed to invoke busdma_swi from swi_vm. Reviewed by: imp, kib Sponsored by: Netflix Differential Revision: https://reviews.freebsd.org/D33447

Add header to hold MD constants and helpers for TLS.

2021-12-09T21:17:13Z

The header exports the following: - Definition of struct tcb. - Helpers to get/set the tcb for the current thread. - TLS_TCB_SIZE (size of TCB) - TLS_TCB_ALIGN (alignment of TCB) - TLS_VARIANT_I or TLS_VARIANT_II - TLS_DTV_OFFSET (bias of pointers in dtv[]) - TLS_TP_OFFSET (bias of "thread pointer" relative to TCB) Note that TLS_TP_OFFSET does not account for if the unbiased thread pointer points to the start of the TCB (arm and x86) or the end of the TCB (MIPS, PowerPC, and RISC-V). Note also that for amd64, the struct tcb does not include the unused tcb_spare field included in the current structure in libthr. libthr does not use this field, and the existing calls in libc and rtld that allocate a TCB for amd64 assume it is the size of 3 Elf_Addr's (and thus do not allocate room for tcb_spare). A header is used by architectures using Variant I TLS which uses a common struct tcb. Reviewed by: kib (older version of x86/tls.h), jrtc27 Sponsored by: The University of Cambridge, Google Inc. Differential Revision: https://reviews.freebsd.org/D33351

mips: Rename TLS_DTP_OFFSET to TLS_DTV_OFFSET.

2021-12-09T21:16:00Z

This is the more standard name for the bias of dtv pointers used on other platforms. This also fixes a few other places that were using the wrong bias previously on MIPS such as dlpi_tls_data in struct dl_phdr_info and the recently added __libc_tls_get_addr(). Reviewed by: kib, jrtc27 Sponsored by: The University of Cambridge, Google Inc. Differential Revision: https://reviews.freebsd.org/D33346

Make struct syscall_args machine independent

2021-12-08T18:45:33Z

After a round of cleanups in late 2020, all definitions are functionally identical. This removes a rotted __aligned(8) on arm. It was added in b7112ead32bc50ef9744099bdbb1cfbd6e906b2a and was intended to align the args member so that 64-bit types (off_t, etc) could be safely read on armeb compiled with clang. With the removal of armev, this is no longer needed (armv7 requires that 32-bit aligned reads of 64-bit values be supported and we enable such support on armv6). As further evidence this is unnecessary, cleanups to struct syscall_args have resulted in args being 32-bit aligned on 32-bit systems. The sole effect is to bloat the struct by 4 bytes. Reviewed by: kib, jhb, imp Differential Revision: https://reviews.freebsd.org/D33308

Implement GET_STACK_USAGE on remaining archs

2021-11-30T15:15:56Z

This definition enables callers to estimate remaining space on the kstack, and take action on it. Notably, it enables optimizations in the GEOM and netgraph subsystems to directly dispatch work items when there is sufficient stack space, rather than queuing them for a worker thread. Implement it for riscv, arm, and mips. Remove the #ifdefs, so it will not go unimplemented elsewhere. PR: 259157 Reviewed by: mav, kib, markj (previous version) MFC after: 1 week Sponsored by: The FreeBSD Foundation Differential Revision: https://reviews.freebsd.org/D32580

netinet: Remove in_cksum_update()

2021-11-24T18:31:15Z

It was never implemented on powerpc or riscv and appears to have been unused since it was added in 1998. No functional change intended. Reviewed by: kp, glebius, cy MFC after: 1 week Sponsored by: The FreeBSD Foundation Differential Revision: https://reviews.freebsd.org/D33093

minidump: Parameterize minidumpsys()

2021-11-19T19:05:52Z

The minidump code is written assuming that certain global state will not change, and rightly so, since it executes from a kernel debugger context. In order to support taking minidumps of a live system, we should allow copies of relevant global state that is likely to change to be passed as parameters to the minidumpsys() function. This patch does the work of parameterizing this function, by adding a struct minidumpstate argument. For now, this struct allows for copies of the kernel message buffer, and the bitset that tracks which pages should be dumped (vm_page_dump). Follow-up changes will actually make use of these arguments. Notably, dump_avail[] does not need a snapshot, since it is not expected to change after system initialization. The existing minidumpsys() definitions are renamed, and a thin MI wrapper is added to kern_dump.c, which handles the construction of the state struct. Thus, calling minidumpsys() remains as simple as before. Reviewed by: kib, markj, jhb Sponsored by: Juniper Networks, Inc. Sponsored by: Klara, Inc. MFC after: 2 weeks Differential Revision: https://reviews.freebsd.org/D31989

minidump: De-duplicate the progress bar

2021-09-29T19:42:21Z

The implementation of the progress bar is simple, but duplicated for most minidump implementations. Extract the common bits to kern_dump.c. Ensure that the bar is reset with each subsequent dump; this was only done on some platforms previously. Reviewed by: markj MFC after: 2 weeks Sponsored by: Juniper Networks, Inc. Sponsored by: Klara, Inc. Differential Revision: https://reviews.freebsd.org/D31885

Create sys/reg.h for the common code previously in machine/reg.h

2021-08-30T11:50:53Z

Move the common kernel function signatures from machine/reg.h to a new sys/reg.h. This is in preperation for adding PT_GETREGSET to ptrace(2). Reviewed by: imp, markj Sponsored by: DARPA, AFRL (original work) Sponsored by: The FreeBSD Foundation Differential Revision: https://reviews.freebsd.org/D19830