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minix/kernel/arch/i386/memory.c
Tomas Hruby 12ef495cac atomicity fix when enabling paging 
- before enabling paging VM asks kernel to resize its segments. This
  may cause kernel to segfault if APIC is used and an interrupt
  happens between this and paging enabled. As these are 2 separate
  vmctl calls it is not atomic. This patch fixes this problem. VM does
  not ask kernel to resize the segments in a separate call anymore.
  The new segments limit is part of the "enable paging" call. It
  generalizes this call in such a way that more information can be
  passed as need be or the information may be completely different if
  another architecture requires this.
2010-03-22 07:42:52 +00:00

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#include "../../kernel.h"
#include "../../proc.h"
#include "../../vm.h"
#include <machine/vm.h>
#include <minix/type.h>
#include <minix/syslib.h>
#include <minix/cpufeature.h>
#include <string.h>
#include <assert.h>
#include <signal.h>
#include <machine/vm.h>
#include "proto.h"
#include "../../proto.h"
#include "../../proto.h"
#include "../../debug.h"
#ifdef CONFIG_APIC
#include "apic.h"
#ifdef CONFIG_WATCHDOG
#include "../../watchdog.h"
#endif
#endif
PRIVATE int psok = 0;
#define PROCPDEPTR(pr, pi) ((u32_t *) ((u8_t *) vm_pagedirs +\
I386_PAGE_SIZE * pr->p_nr + \
I386_VM_PT_ENT_SIZE * pi))
PUBLIC u8_t *vm_pagedirs = NULL;
#define MAX_FREEPDES 3
PRIVATE int nfreepdes = 0, freepdes[MAX_FREEPDES];
#define HASPT(procptr) ((procptr)->p_seg.p_cr3 != 0)
FORWARD _PROTOTYPE( u32_t phys_get32, (phys_bytes v) );
FORWARD _PROTOTYPE( void vm_enable_paging, (void) );
/* *** Internal VM Functions *** */
PUBLIC void vm_init(struct proc *newptproc)
{
if(vm_running)
panic("vm_init: vm_running");
switch_address_space(newptproc);
assert(ptproc == newptproc);
vm_enable_paging();
vm_running = 1;
}
/* This function sets up a mapping from within the kernel's address
* space to any other area of memory, either straight physical
* memory (pr == NULL) or a process view of memory, in 4MB windows.
* I.e., it maps in 4MB chunks of virtual (or physical) address space
* to 4MB chunks of kernel virtual address space.
*
* It recognizes pr already being in memory as a special case (no
* mapping required).
*
* The target (i.e. in-kernel) mapping area is one of the freepdes[]
* VM has earlier already told the kernel about that is available. It is
* identified as the 'pde' parameter. This value can be chosen freely
* by the caller, as long as it is in range (i.e. 0 or higher and corresonds
* to a known freepde slot). It is up to the caller to keep track of which
* freepde's are in use, and to determine which ones are free to use.
*
* The logical number supplied by the caller is translated into an actual
* pde number to be used, and a pointer to it (linear address) is returned
* for actual use by phys_copy or phys_memset.
*/
PRIVATE phys_bytes createpde(
struct proc *pr, /* Requested process, NULL for physical. */
phys_bytes linaddr, /* Address after segment translation. */
phys_bytes *bytes, /* Size of chunk, function may truncate it. */
int pde, /* freepde number to use for the mapping. */
int *changed /* If mapping is made, this is set to 1. */
)
{
u32_t pdeval;
phys_bytes offset;
assert(pde >= 0 && pde < nfreepdes);
pde = freepdes[pde];
if(pr && ((pr == ptproc) || !HASPT(pr))) {
/* Process memory is requested, and
* it's a process that is already in current page table, or
* a process that is in every page table.
* Therefore linaddr is valid directly, with the requested
* size.
*/
return linaddr;
}
if(pr) {
/* Requested address is in a process that is not currently
* accessible directly. Grab the PDE entry of that process'
* page table that corresponds to the requested address.
*/
pdeval = *PROCPDEPTR(pr, I386_VM_PDE(linaddr));
} else {
/* Requested address is physical. Make up the PDE entry. */
pdeval = (linaddr & I386_VM_ADDR_MASK_4MB) |
I386_VM_BIGPAGE | I386_VM_PRESENT |
I386_VM_WRITE | I386_VM_USER;
}
/* Write the pde value that we need into a pde that the kernel
* can access, into the currently loaded page table so it becomes
* visible.
*/
if(*PROCPDEPTR(ptproc, pde) != pdeval) {
*PROCPDEPTR(ptproc, pde) = pdeval;
*changed = 1;
}
/* Memory is now available, but only the 4MB window of virtual
* address space that we have mapped; calculate how much of
* the requested range is visible and return that in *bytes,
* if that is less than the requested range.
*/
offset = linaddr & I386_VM_OFFSET_MASK_4MB; /* Offset in 4MB window. */
*bytes = MIN(*bytes, I386_BIG_PAGE_SIZE - offset);
/* Return the linear address of the start of the new mapping. */
return I386_BIG_PAGE_SIZE*pde + offset;
}
/*===========================================================================*
* lin_lin_copy *
*===========================================================================*/
PRIVATE int lin_lin_copy(struct proc *srcproc, vir_bytes srclinaddr,
struct proc *dstproc, vir_bytes dstlinaddr, vir_bytes bytes)
{
u32_t addr;
int procslot;
NOREC_ENTER(linlincopy);
assert(vm_running);
assert(nfreepdes >= 3);
assert(ptproc);
assert(proc_ptr);
assert(read_cr3() == ptproc->p_seg.p_cr3);
procslot = ptproc->p_nr;
assert(procslot >= 0 && procslot < I386_VM_DIR_ENTRIES);
while(bytes > 0) {
phys_bytes srcptr, dstptr;
vir_bytes chunk = bytes;
int changed = 0;
/* Set up 4MB ranges. */
srcptr = createpde(srcproc, srclinaddr, &chunk, 0, &changed);
dstptr = createpde(dstproc, dstlinaddr, &chunk, 1, &changed);
if(changed)
reload_cr3();
/* Copy pages. */
PHYS_COPY_CATCH(srcptr, dstptr, chunk, addr);
if(addr) {
/* If addr is nonzero, a page fault was caught. */
if(addr >= srcptr && addr < (srcptr + chunk)) {
NOREC_RETURN(linlincopy, EFAULT_SRC);
}
if(addr >= dstptr && addr < (dstptr + chunk)) {
NOREC_RETURN(linlincopy, EFAULT_DST);
}
panic("lin_lin_copy fault out of range");
/* Not reached. */
NOREC_RETURN(linlincopy, EFAULT);
}
/* Update counter and addresses for next iteration, if any. */
bytes -= chunk;
srclinaddr += chunk;
dstlinaddr += chunk;
}
NOREC_RETURN(linlincopy, OK);
}
PRIVATE u32_t phys_get32(phys_bytes addr)
{
u32_t v;
int r;
if(!vm_running) {
phys_copy(addr, vir2phys(&v), sizeof(v));
return v;
}
if((r=lin_lin_copy(NULL, addr,
proc_addr(SYSTEM), vir2phys(&v), sizeof(v))) != OK) {
panic("lin_lin_copy for phys_get32 failed: %d", r);
}
return v;
}
PRIVATE char *cr0_str(u32_t e)
{
static char str[80];
strcpy(str, "");
#define FLAG(v) do { if(e & (v)) { strcat(str, #v " "); e &= ~v; } } while(0)
FLAG(I386_CR0_PE);
FLAG(I386_CR0_MP);
FLAG(I386_CR0_EM);
FLAG(I386_CR0_TS);
FLAG(I386_CR0_ET);
FLAG(I386_CR0_PG);
FLAG(I386_CR0_WP);
if(e) { strcat(str, " (++)"); }
return str;
}
PRIVATE char *cr4_str(u32_t e)
{
static char str[80];
strcpy(str, "");
FLAG(I386_CR4_VME);
FLAG(I386_CR4_PVI);
FLAG(I386_CR4_TSD);
FLAG(I386_CR4_DE);
FLAG(I386_CR4_PSE);
FLAG(I386_CR4_PAE);
FLAG(I386_CR4_MCE);
FLAG(I386_CR4_PGE);
if(e) { strcat(str, " (++)"); }
return str;
}
PRIVATE void vm_enable_paging(void)
{
u32_t cr0, cr4;
int pgeok;
psok = _cpufeature(_CPUF_I386_PSE);
pgeok = _cpufeature(_CPUF_I386_PGE);
cr0= read_cr0();
cr4= read_cr4();
/* First clear PG and PGE flag, as PGE must be enabled after PG. */
write_cr0(cr0 & ~I386_CR0_PG);
write_cr4(cr4 & ~(I386_CR4_PGE | I386_CR4_PSE));
cr0= read_cr0();
cr4= read_cr4();
/* Our first page table contains 4MB entries. */
if(psok)
cr4 |= I386_CR4_PSE;
write_cr4(cr4);
/* First enable paging, then enable global page flag. */
cr0 |= I386_CR0_PG;
write_cr0(cr0 );
cr0 |= I386_CR0_WP;
write_cr0(cr0);
/* May we enable these features? */
if(pgeok)
cr4 |= I386_CR4_PGE;
write_cr4(cr4);
}
PUBLIC vir_bytes alloc_remote_segment(u32_t *selector,
segframe_t *segments, int index, phys_bytes phys, vir_bytes size,
int priv)
{
phys_bytes offset = 0;
/* Check if the segment size can be recorded in bytes, that is, check
* if descriptor's limit field can delimited the allowed memory region
* precisely. This works up to 1MB. If the size is larger, 4K pages
* instead of bytes are used.
*/
if (size < BYTE_GRAN_MAX) {
init_dataseg(&segments->p_ldt[EXTRA_LDT_INDEX+index],
phys, size, priv);
*selector = ((EXTRA_LDT_INDEX+index)*0x08) | (1*0x04) | priv;
offset = 0;
} else {
init_dataseg(&segments->p_ldt[EXTRA_LDT_INDEX+index],
phys & ~0xFFFF, 0, priv);
*selector = ((EXTRA_LDT_INDEX+index)*0x08) | (1*0x04) | priv;
offset = phys & 0xFFFF;
}
return offset;
}
PUBLIC phys_bytes umap_remote(struct proc* rp, int seg,
vir_bytes vir_addr, vir_bytes bytes)
{
/* Calculate the physical memory address for a given virtual address. */
struct far_mem *fm;
#if 0
if(rp->p_misc_flags & MF_FULLVM) return 0;
#endif
if (bytes <= 0) return( (phys_bytes) 0);
if (seg < 0 || seg >= NR_REMOTE_SEGS) return( (phys_bytes) 0);
fm = &rp->p_priv->s_farmem[seg];
if (! fm->in_use) return( (phys_bytes) 0);
if (vir_addr + bytes > fm->mem_len) return( (phys_bytes) 0);
return(fm->mem_phys + (phys_bytes) vir_addr);
}
/*===========================================================================*
* umap_local *
*===========================================================================*/
PUBLIC phys_bytes umap_local(rp, seg, vir_addr, bytes)
register struct proc *rp; /* pointer to proc table entry for process */
int seg; /* T, D, or S segment */
vir_bytes vir_addr; /* virtual address in bytes within the seg */
vir_bytes bytes; /* # of bytes to be copied */
{
/* Calculate the physical memory address for a given virtual address. */
vir_clicks vc; /* the virtual address in clicks */
phys_bytes pa; /* intermediate variables as phys_bytes */
phys_bytes seg_base;
if(seg != T && seg != D && seg != S)
panic("umap_local: wrong seg: %d", seg);
if (bytes <= 0) return( (phys_bytes) 0);
if (vir_addr + bytes <= vir_addr) return 0; /* overflow */
vc = (vir_addr + bytes - 1) >> CLICK_SHIFT; /* last click of data */
if (seg != T)
seg = (vc < rp->p_memmap[D].mem_vir + rp->p_memmap[D].mem_len ? D : S);
else if (rp->p_memmap[T].mem_len == 0) /* common I&D? */
seg = D; /* ptrace needs this */
if ((vir_addr>>CLICK_SHIFT) >= rp->p_memmap[seg].mem_vir +
rp->p_memmap[seg].mem_len) return( (phys_bytes) 0 );
if (vc >= rp->p_memmap[seg].mem_vir +
rp->p_memmap[seg].mem_len) return( (phys_bytes) 0 );
seg_base = (phys_bytes) rp->p_memmap[seg].mem_phys;
seg_base = seg_base << CLICK_SHIFT; /* segment origin in bytes */
pa = (phys_bytes) vir_addr;
pa -= rp->p_memmap[seg].mem_vir << CLICK_SHIFT;
return(seg_base + pa);
}
/*===========================================================================*
* umap_virtual *
*===========================================================================*/
PUBLIC phys_bytes umap_virtual(rp, seg, vir_addr, bytes)
register struct proc *rp; /* pointer to proc table entry for process */
int seg; /* T, D, or S segment */
vir_bytes vir_addr; /* virtual address in bytes within the seg */
vir_bytes bytes; /* # of bytes to be copied */
{
vir_bytes linear;
u32_t phys = 0;
if(seg == MEM_GRANT) {
return umap_grant(rp, (cp_grant_id_t) vir_addr, bytes);
}
if(!(linear = umap_local(rp, seg, vir_addr, bytes))) {
printf("SYSTEM:umap_virtual: umap_local failed\n");
phys = 0;
} else {
if(vm_lookup(rp, linear, &phys, NULL) != OK) {
printf("SYSTEM:umap_virtual: vm_lookup of %s: seg 0x%lx: 0x%lx failed\n", rp->p_name, seg, vir_addr);
phys = 0;
}
if(phys == 0)
panic("vm_lookup returned phys: %d", phys);
}
if(phys == 0) {
printf("SYSTEM:umap_virtual: lookup failed\n");
return 0;
}
/* Now make sure addresses are contiguous in physical memory
* so that the umap makes sense.
*/
if(bytes > 0 && !vm_contiguous(rp, linear, bytes)) {
printf("umap_virtual: %s: %d at 0x%lx (vir 0x%lx) not contiguous\n",
rp->p_name, bytes, linear, vir_addr);
return 0;
}
/* phys must be larger than 0 (or the caller will think the call
* failed), and address must not cross a page boundary.
*/
assert(phys);
return phys;
}
/*===========================================================================*
* vm_lookup *
*===========================================================================*/
PUBLIC int vm_lookup(struct proc *proc, vir_bytes virtual, vir_bytes *physical, u32_t *ptent)
{
u32_t *root, *pt;
int pde, pte;
u32_t pde_v, pte_v;
NOREC_ENTER(vmlookup);
assert(proc);
assert(physical);
assert(!isemptyp(proc));
if(!HASPT(proc)) {
*physical = virtual;
NOREC_RETURN(vmlookup, OK);
}
/* Retrieve page directory entry. */
root = (u32_t *) proc->p_seg.p_cr3;
assert(!((u32_t) root % I386_PAGE_SIZE));
pde = I386_VM_PDE(virtual);
assert(pde >= 0 && pde < I386_VM_DIR_ENTRIES);
pde_v = phys_get32((u32_t) (root + pde));
if(!(pde_v & I386_VM_PRESENT)) {
NOREC_RETURN(vmlookup, EFAULT);
}
/* We don't expect to ever see this. */
if(pde_v & I386_VM_BIGPAGE) {
*physical = pde_v & I386_VM_ADDR_MASK_4MB;
if(ptent) *ptent = pde_v;
*physical += virtual & I386_VM_OFFSET_MASK_4MB;
} else {
/* Retrieve page table entry. */
pt = (u32_t *) I386_VM_PFA(pde_v);
assert(!((u32_t) pt % I386_PAGE_SIZE));
pte = I386_VM_PTE(virtual);
assert(pte >= 0 && pte < I386_VM_PT_ENTRIES);
pte_v = phys_get32((u32_t) (pt + pte));
if(!(pte_v & I386_VM_PRESENT)) {
NOREC_RETURN(vmlookup, EFAULT);
}
if(ptent) *ptent = pte_v;
/* Actual address now known; retrieve it and add page offset. */
*physical = I386_VM_PFA(pte_v);
*physical += virtual % I386_PAGE_SIZE;
}
NOREC_RETURN(vmlookup, OK);
}
/*===========================================================================*
* vm_contiguous *
*===========================================================================*/
PUBLIC int vm_contiguous(struct proc *targetproc, u32_t vir_buf, size_t bytes)
{
int first = 1, r;
u32_t prev_phys = 0; /* Keep lints happy. */
u32_t po;
assert(targetproc);
assert(bytes > 0);
if(!HASPT(targetproc))
return 1;
/* Start and end at page boundary to make logic simpler. */
po = vir_buf % I386_PAGE_SIZE;
if(po > 0) {
bytes += po;
vir_buf -= po;
}
po = (vir_buf + bytes) % I386_PAGE_SIZE;
if(po > 0)
bytes += I386_PAGE_SIZE - po;
/* Keep going as long as we cross a page boundary. */
while(bytes > 0) {
u32_t phys;
if((r=vm_lookup(targetproc, vir_buf, &phys, NULL)) != OK) {
printf("vm_contiguous: vm_lookup failed, %d\n", r);
printf("kernel stack: ");
util_stacktrace();
return 0;
}
if(!first) {
if(prev_phys+I386_PAGE_SIZE != phys) {
printf("vm_contiguous: no (0x%lx, 0x%lx)\n",
prev_phys, phys);
printf("kernel stack: ");
util_stacktrace();
return 0;
}
}
first = 0;
prev_phys = phys;
vir_buf += I386_PAGE_SIZE;
bytes -= I386_PAGE_SIZE;
}
return 1;
}
/*===========================================================================*
* vm_suspend *
*===========================================================================*/
PRIVATE void vm_suspend(struct proc *caller, struct proc *target,
vir_bytes linaddr, vir_bytes len, int type)
{
/* This range is not OK for this process. Set parameters
* of the request and notify VM about the pending request.
*/
assert(!RTS_ISSET(caller, RTS_VMREQUEST));
assert(!RTS_ISSET(target, RTS_VMREQUEST));
RTS_SET(caller, RTS_VMREQUEST);
caller->p_vmrequest.req_type = VMPTYPE_CHECK;
caller->p_vmrequest.target = target->p_endpoint;
caller->p_vmrequest.params.check.start = linaddr;
caller->p_vmrequest.params.check.length = len;
caller->p_vmrequest.params.check.writeflag = 1;
caller->p_vmrequest.type = type;
/* Connect caller on vmrequest wait queue. */
if(!(caller->p_vmrequest.nextrequestor = vmrequest))
send_sig(VM_PROC_NR, SIGKMEM);
vmrequest = caller;
}
/*===========================================================================*
* delivermsg *
*===========================================================================*/
int delivermsg(struct proc *rp)
{
phys_bytes addr;
int r;
NOREC_ENTER(deliver);
assert(rp->p_misc_flags & MF_DELIVERMSG);
assert(rp->p_delivermsg.m_source != NONE);
assert(rp->p_delivermsg_lin);
assert(rp->p_delivermsg_lin == umap_local(rp, D, rp->p_delivermsg_vir, sizeof(message)));
PHYS_COPY_CATCH(vir2phys(&rp->p_delivermsg),
rp->p_delivermsg_lin, sizeof(message), addr);
if(addr) {
vm_suspend(rp, rp, rp->p_delivermsg_lin, sizeof(message),
VMSTYPE_DELIVERMSG);
r = VMSUSPEND;
} else {
/* Indicate message has been delivered; address is 'used'. */
rp->p_delivermsg.m_source = NONE;
rp->p_delivermsg_lin = 0;
rp->p_misc_flags &= ~MF_DELIVERMSG;
r = OK;
}
NOREC_RETURN(deliver, r);
}
PRIVATE char *flagstr(u32_t e, int dir)
{
static char str[80];
strcpy(str, "");
FLAG(I386_VM_PRESENT);
FLAG(I386_VM_WRITE);
FLAG(I386_VM_USER);
FLAG(I386_VM_PWT);
FLAG(I386_VM_PCD);
FLAG(I386_VM_GLOBAL);
if(dir)
FLAG(I386_VM_BIGPAGE); /* Page directory entry only */
else
FLAG(I386_VM_DIRTY); /* Page table entry only */
return str;
}
PRIVATE void vm_pt_print(u32_t *pagetable, u32_t v)
{
int pte;
int col = 0;
assert(!((u32_t) pagetable % I386_PAGE_SIZE));
for(pte = 0; pte < I386_VM_PT_ENTRIES; pte++) {
u32_t pte_v, pfa;
pte_v = phys_get32((u32_t) (pagetable + pte));
if(!(pte_v & I386_VM_PRESENT))
continue;
pfa = I386_VM_PFA(pte_v);
printf("%4d:%08lx:%08lx %2s ",
pte, v + I386_PAGE_SIZE*pte, pfa,
(pte_v & I386_VM_WRITE) ? "rw":"RO");
col++;
if(col == 3) { printf("\n"); col = 0; }
}
if(col > 0) printf("\n");
return;
}
PRIVATE void vm_print(u32_t *root)
{
int pde;
assert(!((u32_t) root % I386_PAGE_SIZE));
printf("page table 0x%lx:\n", root);
for(pde = 0; pde < I386_VM_DIR_ENTRIES; pde++) {
u32_t pde_v;
u32_t *pte_a;
pde_v = phys_get32((u32_t) (root + pde));
if(!(pde_v & I386_VM_PRESENT))
continue;
if(pde_v & I386_VM_BIGPAGE) {
printf("%4d: 0x%lx, flags %s\n",
pde, I386_VM_PFA(pde_v), flagstr(pde_v, 1));
} else {
pte_a = (u32_t *) I386_VM_PFA(pde_v);
printf("%4d: pt %08lx %s\n",
pde, pte_a, flagstr(pde_v, 1));
vm_pt_print(pte_a, pde * I386_VM_PT_ENTRIES * I386_PAGE_SIZE);
printf("\n");
}
}
return;
}
/*===========================================================================*
* lin_memset *
*===========================================================================*/
int vm_phys_memset(phys_bytes ph, u8_t c, phys_bytes bytes)
{
u32_t p;
NOREC_ENTER(physmemset);
p = c | (c << 8) | (c << 16) | (c << 24);
if(!vm_running) {
phys_memset(ph, p, bytes);
NOREC_RETURN(physmemset, OK);
}
assert(nfreepdes >= 3);
/* With VM, we have to map in the physical memory.
* We can do this 4MB at a time.
*/
while(bytes > 0) {
int changed = 0;
phys_bytes chunk = bytes, ptr;
ptr = createpde(NULL, ph, &chunk, 0, &changed);
if(changed)
reload_cr3();
/* We can memset as many bytes as we have remaining,
* or as many as remain in the 4MB chunk we mapped in.
*/
phys_memset(ptr, p, chunk);
bytes -= chunk;
ph += chunk;
}
NOREC_RETURN(physmemset, OK);
}
/*===========================================================================*
* virtual_copy_f *
*===========================================================================*/
PUBLIC int virtual_copy_f(caller, src_addr, dst_addr, bytes, vmcheck)
struct proc * caller;
struct vir_addr *src_addr; /* source virtual address */
struct vir_addr *dst_addr; /* destination virtual address */
vir_bytes bytes; /* # of bytes to copy */
int vmcheck; /* if nonzero, can return VMSUSPEND */
{
/* Copy bytes from virtual address src_addr to virtual address dst_addr.
* Virtual addresses can be in ABS, LOCAL_SEG, REMOTE_SEG, or BIOS_SEG.
*/
struct vir_addr *vir_addr[2]; /* virtual source and destination address */
phys_bytes phys_addr[2]; /* absolute source and destination */
int seg_index;
int i;
struct proc *procs[2];
NOREC_ENTER(virtualcopy);
assert((vmcheck && caller) || (!vmcheck && !caller));
/* Check copy count. */
if (bytes <= 0) return(EDOM);
/* Do some more checks and map virtual addresses to physical addresses. */
vir_addr[_SRC_] = src_addr;
vir_addr[_DST_] = dst_addr;
for (i=_SRC_; i<=_DST_; i++) {
int proc_nr, type;
struct proc *p;
type = vir_addr[i]->segment & SEGMENT_TYPE;
if((type != PHYS_SEG && type != BIOS_SEG) &&
isokendpt(vir_addr[i]->proc_nr_e, &proc_nr))
p = proc_addr(proc_nr);
else
p = NULL;
procs[i] = p;
/* Get physical address. */
switch(type) {
case LOCAL_SEG:
case LOCAL_VM_SEG:
if(!p) {
NOREC_RETURN(virtualcopy, EDEADSRCDST);
}
seg_index = vir_addr[i]->segment & SEGMENT_INDEX;
if(type == LOCAL_SEG)
phys_addr[i] = umap_local(p, seg_index, vir_addr[i]->offset,
bytes);
else
phys_addr[i] = umap_virtual(p, seg_index,
vir_addr[i]->offset, bytes);
if(phys_addr[i] == 0) {
printf("virtual_copy: map 0x%x failed for %s seg %d, "
"offset %lx, len %d, i %d\n",
type, p->p_name, seg_index, vir_addr[i]->offset,
bytes, i);
}
break;
case REMOTE_SEG:
if(!p) {
NOREC_RETURN(virtualcopy, EDEADSRCDST);
}
seg_index = vir_addr[i]->segment & SEGMENT_INDEX;
phys_addr[i] = umap_remote(p, seg_index, vir_addr[i]->offset, bytes);
break;
#if _MINIX_CHIP == _CHIP_INTEL
case BIOS_SEG:
phys_addr[i] = umap_bios(vir_addr[i]->offset, bytes );
break;
#endif
case PHYS_SEG:
phys_addr[i] = vir_addr[i]->offset;
break;
default:
printf("virtual_copy: strange type 0x%x\n", type);
NOREC_RETURN(virtualcopy, EINVAL);
}
/* Check if mapping succeeded. */
if (phys_addr[i] <= 0 && vir_addr[i]->segment != PHYS_SEG) {
printf("virtual_copy EFAULT\n");
NOREC_RETURN(virtualcopy, EFAULT);
}
}
if(vm_running) {
int r;
if(caller && RTS_ISSET(caller, RTS_VMREQUEST)) {
assert(caller->p_vmrequest.vmresult != VMSUSPEND);
RTS_UNSET(caller, RTS_VMREQUEST);
if(caller->p_vmrequest.vmresult != OK) {
NOREC_RETURN(virtualcopy, caller->p_vmrequest.vmresult);
}
}
if((r=lin_lin_copy(procs[_SRC_], phys_addr[_SRC_],
procs[_DST_], phys_addr[_DST_], bytes)) != OK) {
struct proc *target;
phys_bytes lin;
if(r != EFAULT_SRC && r != EFAULT_DST)
panic("lin_lin_copy failed: %d", r);
if(!vmcheck || !caller) {
NOREC_RETURN(virtualcopy, r);
}
assert(procs[_SRC_] && procs[_DST_]);
if(r == EFAULT_SRC) {
lin = phys_addr[_SRC_];
target = procs[_SRC_];
} else if(r == EFAULT_DST) {
lin = phys_addr[_DST_];
target = procs[_DST_];
} else {
panic("r strange: %d", r);
}
vm_suspend(caller, target, lin, bytes, VMSTYPE_KERNELCALL);
NOREC_RETURN(virtualcopy, VMSUSPEND);
}
NOREC_RETURN(virtualcopy, OK);
}
assert(!vm_running);
/* can't copy to/from process with PT without VM */
#define NOPT(p) (!(p) || !HASPT(p))
if(!NOPT(procs[_SRC_])) {
printf("ignoring page table src: %s / %d at 0x%lx\n",
procs[_SRC_]->p_name, procs[_SRC_]->p_endpoint, procs[_SRC_]->p_seg.p_cr3);
}
if(!NOPT(procs[_DST_])) {
printf("ignoring page table dst: %s / %d at 0x%lx\n",
procs[_DST_]->p_name, procs[_DST_]->p_endpoint,
procs[_DST_]->p_seg.p_cr3);
}
/* Now copy bytes between physical addresseses. */
if(phys_copy(phys_addr[_SRC_], phys_addr[_DST_], (phys_bytes) bytes))
NOREC_RETURN(virtualcopy, EFAULT);
NOREC_RETURN(virtualcopy, OK);
}
/*===========================================================================*
* data_copy *
*===========================================================================*/
PUBLIC int data_copy(endpoint_t from_proc, vir_bytes from_addr,
endpoint_t to_proc, vir_bytes to_addr,
size_t bytes)
{
struct vir_addr src, dst;
src.segment = dst.segment = D;
src.offset = from_addr;
dst.offset = to_addr;
src.proc_nr_e = from_proc;
dst.proc_nr_e = to_proc;
return virtual_copy(&src, &dst, bytes);
}
/*===========================================================================*
* data_copy_vmcheck *
*===========================================================================*/
PUBLIC int data_copy_vmcheck(struct proc * caller,
endpoint_t from_proc, vir_bytes from_addr,
endpoint_t to_proc, vir_bytes to_addr,
size_t bytes)
{
struct vir_addr src, dst;
src.segment = dst.segment = D;
src.offset = from_addr;
dst.offset = to_addr;
src.proc_nr_e = from_proc;
dst.proc_nr_e = to_proc;
return virtual_copy_vmcheck(caller, &src, &dst, bytes);
}
/*===========================================================================*
* arch_pre_exec *
*===========================================================================*/
PUBLIC void arch_pre_exec(struct proc *pr, u32_t ip, u32_t sp)
{
/* wipe extra LDT entries, set program counter, and stack pointer. */
memset(pr->p_seg.p_ldt + EXTRA_LDT_INDEX, 0,
sizeof(pr->p_seg.p_ldt[0]) * (LDT_SIZE - EXTRA_LDT_INDEX));
pr->p_reg.pc = ip;
pr->p_reg.sp = sp;
}
/*===========================================================================*
* arch_umap *
*===========================================================================*/
PUBLIC int arch_umap(struct proc *pr, vir_bytes offset, vir_bytes count,
int seg, phys_bytes *addr)
{
switch(seg) {
case BIOS_SEG:
*addr = umap_bios(offset, count);
return OK;
}
/* This must be EINVAL; the umap fallback function in
* lib/syslib/alloc_util.c depends on it to detect an
* older kernel (as opposed to mapping error).
*/
return EINVAL;
}
/* VM reports page directory slot we're allowed to use freely. */
void i386_freepde(int pde)
{
if(nfreepdes >= MAX_FREEPDES)
return;
freepdes[nfreepdes++] = pde;
}
PUBLIC int arch_phys_map(int index, phys_bytes *addr, phys_bytes *len, int *flags)
{
#ifdef CONFIG_APIC
/* map the local APIC if enabled */
if (index == 0 && lapic_addr) {
*addr = vir2phys(lapic_addr);
*len = 4 << 10 /* 4kB */;
*flags = VMMF_UNCACHED;
return OK;
}
return EINVAL;
#else
/* we don't want anything */
return EINVAL;
#endif
}
PUBLIC int arch_phys_map_reply(int index, vir_bytes addr)
{
#ifdef CONFIG_APIC
/* if local APIC is enabled */
if (index == 0 && lapic_addr) {
lapic_addr_vaddr = addr;
}
#endif
return OK;
}
PUBLIC int arch_enable_paging(struct proc * caller, message * m_ptr)
{
struct vm_ep_data ep_data;
int r;
/*
* copy the extra data associated with the call from userspace
*/
if((r=data_copy(caller->p_endpoint, (vir_bytes)m_ptr->SVMCTL_VALUE,
KERNEL, (vir_bytes) &ep_data, sizeof(ep_data))) != OK) {
printf("vmctl_enable_paging: data_copy failed! (%d)\n", r);
return r;
}
/*
* when turning paging on i386 we also change the segment limits to make
* the special mappings requested by the kernel reachable
*/
if ((r = prot_set_kern_seg_limit(ep_data.data_seg_limit)) != OK)
return r;
/*
* install the new map provided by the call
*/
if (newmap(caller, caller, ep_data.mem_map) != OK)
panic("arch_enable_paging: newmap failed");
FIXLINMSG(caller);
assert(caller->p_delivermsg_lin == umap_local(caller, D,
caller->p_delivermsg_vir, sizeof(message)));
#ifdef CONFIG_APIC
/* if local APIC is enabled */
if (lapic_addr) {
lapic_addr = lapic_addr_vaddr;
lapic_eoi_addr = LAPIC_EOI;
}
#endif
#ifdef CONFIG_WATCHDOG
/*
* We make sure that we don't enable the watchdog until paging is turned
* on as we might get a NMI while switching and we might still use wrong
* lapic address. Bad things would happen. It is unfortunate but such is
* life
*/
i386_watchdog_start();
#endif
return OK;
}
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