diff options
Diffstat (limited to 'sys/arch/amd64')
-rw-r--r-- | sys/arch/amd64/amd64/proc_machdep.c | 107 |
1 files changed, 107 insertions, 0 deletions
diff --git a/sys/arch/amd64/amd64/proc_machdep.c b/sys/arch/amd64/amd64/proc_machdep.c new file mode 100644 index 0000000..eb3866a --- /dev/null +++ b/sys/arch/amd64/amd64/proc_machdep.c @@ -0,0 +1,107 @@ +/* + * Copyright (c) 2023-2024 Ian Marco Moffett and the Osmora Team. + * All rights reserved. + * + * Redistribution and use in source and binary forms, with or without + * modification, are permitted provided that the following conditions are met: + * + * 1. Redistributions of source code must retain the above copyright notice, + * this list of conditions and the following disclaimer. + * 2. Redistributions in binary form must reproduce the above copyright + * notice, this list of conditions and the following disclaimer in the + * documentation and/or other materials provided with the distribution. + * 3. Neither the name of Hyra nor the names of its + * contributors may be used to endorse or promote products derived from + * this software without specific prior written permission. + * + * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS" + * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE + * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE + * ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE + * LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR + * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF + * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS + * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN + * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) + * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE + * POSSIBILITY OF SUCH DAMAGE. + */ + +#include <sys/proc.h> +#include <sys/types.h> +#include <sys/param.h> +#include <sys/errno.h> +#include <machine/frame.h> +#include <machine/gdt.h> +#include <vm/physmem.h> +#include <vm/vm.h> +#include <vm/map.h> +#include <string.h> + +/* + * MD thread init code + * + * @p: New process. + * @parent: Parent of new process. + * @ip: Instruction pointer. + */ +int +md_td_init(struct proc *p, struct proc *parent, uintptr_t ip) +{ + uintptr_t stack_base; + struct trapframe *tfp, *parent_tfp; + struct pcb *pcbp; + uint8_t rpl; + int error; + + tfp = &p->tf; + + /* Create a new VAS for this thread */ + pcbp = &p->pcb; + if ((error = pmap_new_vas(&pcbp->addrsp)) != 0) + return error; + + /* + * If parent is NULL, assume kernel space and zero the + * trapframe. Otherwise we can just set it up normally. + */ + if (parent == NULL) { + rpl = 0; + memset(tfp, 0, sizeof(*tfp)); + } else { + parent_tfp = &parent->tf; + rpl = parent_tfp->cs & 3; + memcpy(tfp, &parent->tf, sizeof(*tfp)); + } + + /* + * RPL being 3 indicates that the parent thread is in + * userland. If this is the case, we'd want this new thread + * to also be in userland. + */ + tfp->rip = ip; + tfp->cs = (rpl == 3) ? (USER_CS | 3) : KERNEL_CS; + tfp->ss = (rpl == 3) ? (USER_DS | 3) : KERNEL_DS; + tfp->rflags = 0x202; + + /* Try to allocate a new stack */ + stack_base = vm_alloc_frame(PROC_STACK_PAGES); + if (stack_base == 0) + return -ENOMEM; + + /* + * If RPL is 0 (kernel), adjust the stack base to the + * higher half. If we have an RPL of 3 (user) then we'll + * need to identity map the stack. + */ + if (rpl == 0) { + stack_base += VM_HIGHER_HALF; + } else { + vm_map(pcbp->addrsp, stack_base, stack_base, + PROT_READ | PROT_WRITE | PROT_USER, PROC_STACK_PAGES); + } + + p->stack_base = stack_base; + tfp->rsp = ALIGN_DOWN((stack_base + PROC_STACK_SIZE) - 1, 16); + return 0; +} |