src/sys/i386/include/frame.h, branch main

sys: Remove $FreeBSD$: two-line .h pattern

2023-08-16T17:54:11Z

Remove /^\s*\*\n \*\s+\$FreeBSD\$$\n/

i386 4/4G split.

2018-04-13T20:30:49Z

The change makes the user and kernel address spaces on i386 independent, giving each almost the full 4G of usable virtual addresses except for one PDE at top used for trampoline and per-CPU trampoline stacks, and system structures that must be always mapped, namely IDT, GDT, common TSS and LDT, and process-private TSS and LDT if allocated. By using 1:1 mapping for the kernel text and data, it appeared possible to eliminate assembler part of the locore.S which bootstraps initial page table and KPTmap. The code is rewritten in C and moved into the pmap_cold(). The comment in vmparam.h explains the KVA layout. There is no PCID mechanism available in protected mode, so each kernel/user switch forth and back completely flushes the TLB, except for the trampoline PTD region. The TLB invalidations for userspace becomes trivial, because IPI handlers switch page tables. On the other hand, context switches no longer need to reload %cr3. copyout(9) was rewritten to use vm_fault_quick_hold(). An issue for new copyout(9) is compatibility with wiring user buffers around sysctl handlers. This explains two kind of locks for copyout ptes and accounting of the vslock() calls. The vm_fault_quick_hold() AKA slow path, is only tried after the 'fast path' failed, which temporary changes mapping to the userspace and copies the data to/from small per-cpu buffer in the trampoline. If a page fault occurs during the copy, it is short-circuit by exception.s to not even reach C code. The change was motivated by the need to implement the Meltdown mitigation, but instead of KPTI the full split is done. The i386 architecture already shows the sizing problems, in particular, it is impossible to link clang and lld with debugging. I expect that the issues due to the virtual address space limits would only exaggerate and the split gives more liveness to the platform. Tested by: pho Discussed with: bde Sponsored by: The FreeBSD Foundation MFC after: 1 month Differential revision: https://reviews.freebsd.org/D14633

Renumber copyright clause 4

2017-02-28T23:42:47Z

Renumber cluase 4 to 3, per what everybody else did when BSD granted them permission to remove clause 3. My insistance on keeping the same numbering for legal reasons is too pedantic, so give up on that point. Submitted by: Jan Schaumann Pull Request: https://github.com/freebsd/freebsd/pull/96

Duplicate the copyright from the i386/i386/machdep.c into

2015-07-10T09:15:06Z

i386/include/frame.h after a code was moved from machdep.c to frame.h in r284925. Use include guards style similar to other guards. Noted by: bde Sponsored by: The FreeBSD Foundation MFC after: 1 week

Move CS_SECURE() and EFL_SECURE() macros to the machine/frame.h. They

2015-06-29T10:35:00Z

are useful for most implementations of sendsig(). Sponsored by: The FreeBSD Foundation MFC after: 1 week

Convert machine/elf.h, machine/frame.h, machine/sigframe.h,

2013-02-20T17:39:52Z

machine/signal.h and machine/ucontext.h into common x86 includes, copying from amd64 and merging with i386. Kernel-only compat definitions are kept in the i386/include/sigframe.h and i386/include/signal.h, to reduce amd64 kernel namespace pollution. The amd64 compat uses its own definitions so far. The _MACHINE_ELF_WANT_32BIT definition is to allow the sys/boot/userboot/userboot/elf32_freebsd.c to use i386 ELF definitions on the amd64 compile host. The same hack could be usefully abused by other code too.

Tweak how the MD code calls the fooclock() methods some. Instead of

2005-12-22T22:16:09Z

passing a pointer to an opaque clockframe structure and requiring the MD code to supply CLKF_FOO() macros to extract needed values out of the opaque structure, just pass the needed values directly. In practice this means passing the pair (usermode, pc) to hardclock() and profclock() and passing the boolean (usermode) to hardclock_cpu() and hardclock_process(). Other details: - Axe clockframe and CLKF_FOO() macros on all architectures. Basically, all the archs were taking a trapframe and converting it into a clockframe one way or another. Now they can just extract the PC and usermode values directly out of the trapframe and pass it to fooclock(). - Renamed hardclock_process() to hardclock_cpu() as the latter is more accurate. - On Alpha, we now run profclock() at hz (profhz == hz) rather than at the slower stathz. - On Alpha, for the TurboLaser machines that don't have an 8254 timecounter, call hardclock() directly. This removes an extra conditional check from every clock interrupt on Alpha on the BSP. There is probably room for even further pruning here by changing Alpha to use the simplified timecounter we use on x86 with the lapic timer since we don't get interrupts from the 8254 on Alpha anyway. - On x86, clkintr() shouldn't ever be called now unless using_lapic_timer is false, so add a KASSERT() to that affect and remove a condition to slightly optimize the non-lapic case. - Change prototypeof arm_handler_execute() so that it's first arg is a trapframe pointer rather than a void pointer for clarity. - Use KCOUNT macro in profclock() to lookup the kernel profiling bucket. Tested on: alpha, amd64, arm, i386, ia64, sparc64 Reviewed by: bde (mostly)

Change the i386 code to pass the interrupt vector as a separate argument

2005-12-05T22:39:09Z

rather than embedding it in the intrframe as if_vec. This reduces diffs with amd64 somewhat. - Remove cf_vec from clockframe (it wasn't used anyway) and stop pushing dummy vector arguments for ipi_bitmap_handler() and lapic_handle_timer() since clockframe == trapframe now. - Fix ddb to handle stack traces across interrupt entry points that just have a trapframe on their stack and not a trapframe + vector. - Change intr_execute_handlers() to take a trapframe rather than an intrframe pointer. - Change lapic_handle_intr() and atpic_handle_intr() to take a vector and trapframe rather than an intrframe. - GC struct intrframe now that nothing uses it anymore. - GC CLOCK_TO_TRAPFRAME() and INTR_TO_TRAPFRAME(). Reviewed by: bde Requested by: peter

Update for the KDB framework:

2004-07-10T22:11:14Z

o s/ddb_on_nmi/kdb_on_nmi/g o Rename sysctl machdep.ddb_on_nmi to machdep.kdb_on_nmi o Make debugging support conditional upon KDB instead of DDB. o Call kdb_reenter() when kdb_active is non-zero. o Call kdb_trap() to enter the debugger when not already active. o Update comments accordingly. o Remove misplaced prototype of kdb_trap().

Remove advertising clause from University of California Regent's

2004-04-07T20:46:16Z

license, per letter dated July 22, 1999 and email from Peter Wemm, Alan Cox and Robert Watson. Approved by: core, peter, alc, rwatson