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-rw-r--r--kernel/vm.c127
1 files changed, 73 insertions, 54 deletions
diff --git a/kernel/vm.c b/kernel/vm.c
index a700bcb..814ff12 100644
--- a/kernel/vm.c
+++ b/kernel/vm.c
@@ -95,13 +95,19 @@ static uint32_t ptcount(pte_t *ptr, bool_t dir)
}
// decode a PDE
-static void pde_prt(uint32_t level, uint32_t i, uint32_t entry)
+static void pde_prt(uint32_t level, uint32_t i, uint32_t entry, bool_t all)
{
+ if (!IS_PRESENT(entry) && !all) {
+ return;
+ }
+
// indent
for (int n = 0; n <= level; ++n)
cio_puts(" ");
+
// line header
- cio_printf("[%08x] %08x", i, entry);
+ cio_printf("[%03x] %08x", i, entry);
+
// perms
if (IS_LARGE(entry)) { // PS is 1
if ((entry & PDE_PAT) != 0)
@@ -122,43 +128,49 @@ static void pde_prt(uint32_t level, uint32_t i, uint32_t entry)
cio_puts(" U");
if ((entry & PDE_RW) != 0)
cio_puts(" W");
- cio_puts((entry & PDE_P) != 0 ? " P" : "!P");
- cio_printf(" --> %s %08x", IS_LARGE(entry) ? "Pg" : "PT", PDE_ADDR(entry));
+ // frame address
+ cio_printf(" P --> %s %08x\n", IS_LARGE(entry) ? "Pg" : "PT",
+ PDE_ADDR(entry));
}
// decode a PTE
-static void pte_prt(uint32_t level, uint32_t i, uint32_t entry)
+static void pte_prt(uint32_t level, uint32_t i, uint32_t entry, bool_t all)
{
+ if (!IS_PRESENT(entry) && !all) {
+ return;
+ }
+
// indent
for (int n = 0; n <= level; ++n)
cio_puts(" ");
+
// line header
- cio_printf("[%08x] %08x", i, entry);
+ cio_printf("[%03x] %08x", i, entry);
+
// perms
- if ((entry & PDE_G) != 0)
+ if ((entry & PTE_G) != 0)
cio_puts(" G");
- if ((entry & PDE_PAT) != 0)
+ if ((entry & PTE_PAT) != 0)
cio_puts(" PAT");
- if ((entry & PDE_D) != 0)
+ if ((entry & PTE_D) != 0)
cio_puts(" D");
- if ((entry & PDE_A) != 0)
+ if ((entry & PTE_A) != 0)
cio_puts(" A");
- if ((entry & PDE_PCD) != 0)
+ if ((entry & PTE_PCD) != 0)
cio_puts(" CD");
- if ((entry & PDE_PWT) != 0)
+ if ((entry & PTE_PWT) != 0)
cio_puts(" WT");
- if ((entry & PDE_US) != 0)
+ if ((entry & PTE_US) != 0)
cio_puts(" U");
- if ((entry & PDE_RW) != 0)
+ if ((entry & PTE_RW) != 0)
cio_puts(" W");
- cio_puts((entry & PDE_P) != 0 ? " P" : "!P");
- cio_printf(" --> Pg %08x", PTE_ADDR(entry));
+ cio_printf(" P --> Pg %08x\n", PTE_ADDR(entry));
}
/**
-** Name: pdump
+** Name: ptdump
**
** Recursive helper for table hierarchy dump.
**
@@ -168,40 +180,44 @@ static void pte_prt(uint32_t level, uint32_t i, uint32_t entry)
** @param mode How to display the entries
*/
ATTR_UNUSED
-static void pdump(uint_t level, void *pt, bool_t dir, enum vmmode_e mode)
+static void ptdump(uint_t level, void *pt, bool_t dir, enum vmmode_e mode)
{
pte_t *ptr = (pte_t *)pt;
- cio_printf("? at 0x%08x:", dir ? "PDir" : "PTbl", (uint32_t)pt);
+ // indent two spaces per level
+ for (int n = 0; n < level; ++n)
+ cio_puts(" ");
+
+ cio_printf("%s at 0x%08x:", dir ? "PDir" : "PTbl", (uint32_t)pt);
uint32_t nums = ptcount(ptr, dir);
if (dir) {
- cio_printf(" %u 4MB", (nums >> 16));
+ cio_printf(" 4MB=%u", (nums >> 16));
}
- cio_printf(" %u P %u !P\n", nums & 0xffff,
+ cio_printf(" P=%u !P=%u\n", nums & 0xffff,
N_PTE - ((nums >> 16) + (nums & 0xffff)));
for (uint32_t i = 0; i < (uint32_t)N_PTE; ++i) {
- pte_t entry = *ptr;
- if (dir) {
- // this is a PDIR entry; could be either a 4MB
- // page, or a PMT pointer
- if (mode > Simple) {
- pde_prt(level, i, entry);
- cio_putchar('\n');
- if (!IS_LARGE(entry)) {
- pdump(level + 1, (void *)*ptr, false, mode);
+ pte_t entry = *ptr++;
+
+ // only process this entry if it's not empty
+ if (entry) {
+ if (dir) {
+ // this is a PDIR entry; could be either a 4MB
+ // page, or a PMT pointer
+ if (mode > Simple) {
+ pde_prt(level, i, entry, false);
+ if (!IS_LARGE(entry) && mode > OneLevel) {
+ ptdump(level + 1, (void *)P2V(PTE_ADDR(entry)), false,
+ mode);
+ }
+ }
+ } else {
+ // just a PMT entry
+ if (mode > Simple) {
+ pte_prt(level, i, entry, false);
}
- }
- } else {
- // just a PMT entry
- if (mode > Simple) {
- pte_prt(level, i, entry);
- cio_putchar('\n');
}
}
-
- // move to the next entry
- ++ptr;
}
}
@@ -285,7 +301,7 @@ void vm_init(void)
// add the entries for the user address space
for (uint32_t addr = 0; addr < NUM_4MB; addr += SZ_PAGE) {
- int stat = vm_map(kpdir, (void *)addr, addr, SZ_PAGE, PTE_RW);
+ int stat = vm_map(kpdir, (void *)addr, addr, SZ_PAGE, PTE_US | PTE_RW);
if (stat != SUCCESS) {
cio_printf("vm_init, map %08x->%08x failed, status %d\n", addr,
addr, stat);
@@ -315,8 +331,8 @@ void vm_init(void)
**
** Convert a user VA into a kernel address. Works for all addresses -
** if the address is a page address, the low-order nine bits will be
-** zeroes; otherwise, they is the offset into the page, which is
-** unchanged within the address spaces.
+** zeroes; otherwise, they are the offset into the page, which is
+** unchanged between the address spaces.
**
** @param pdir Pointer to the page directory to examine
** @param va Virtual address to check
@@ -333,7 +349,7 @@ void *vm_uva2kva(pde_t *pdir, void *va)
pte_t entry = *pte;
// is this a valid address for the user?
- if (IS_PRESENT(entry)) {
+ if (!IS_PRESENT(entry)) {
return NULL;
}
@@ -477,7 +493,7 @@ pte_t *vm_getpte(pde_t *pdir, const void *va, bool_t alloc)
// NOTE: the allocator is serving us virtual page addresses,
// so we must convert them to physical addresses for the
// table entries
- *pde_ptr = V2P(ptbl) | PDE_P | PDE_RW;
+ *pde_ptr = V2P(ptbl) | PDE_P | PDE_RW | PDE_US;
}
// finally, return a pointer to the entry in the page table for this VA
@@ -630,7 +646,7 @@ int vm_add(pde_t *pdir, bool_t wr, bool_t sys, void *va, uint32_t size,
if (wr) {
entrybase |= PTE_RW;
}
- if (sys) {
+ if (!sys) {
entrybase |= PTE_US;
}
@@ -664,7 +680,7 @@ int vm_add(pde_t *pdir, bool_t wr, bool_t sys, void *va, uint32_t size,
memclr(page, SZ_PAGE);
// create the PTE for this frame
- uint32_t entry = (uint32_t)(PTE_ADDR(V2P(page)) | entrybase);
+ uint32_t entry = (uint32_t)(V2P(PTE_ADDR(page)) | entrybase);
*pte = entry;
// copy data if we need to
@@ -711,6 +727,7 @@ void vm_free(pde_t *pdir)
pde_t *curr = pdir;
int nf = 0;
int nt = 0;
+
for (int i = 0; i < N_PDE; ++i) {
// the entry itself
pde_t entry = *curr;
@@ -721,14 +738,15 @@ void vm_free(pde_t *pdir)
assert(!IS_LARGE(entry));
// get the PMT pointer
- pte_t *pmt = (pte_t *)PTE_ADDR(entry);
+ pte_t *pmt = (pte_t *)P2V(PTE_ADDR(entry));
// walk the PMT
for (int j = 0; j < N_PTE; ++j) {
+ pte_t tmp = *pmt;
// does this entry point to a frame?
- if (IS_PRESENT(*pmt)) {
+ if (IS_PRESENT(tmp)) {
// yes - free the frame
- km_page_free((void *)PTE_ADDR(*pmt));
+ km_page_free((void *)P2V(PTE_ADDR(tmp)));
++nf;
// mark it so we don't get surprised
*pmt = 0;
@@ -737,7 +755,7 @@ void vm_free(pde_t *pdir)
++pmt;
}
// now, free the PMT itself
- km_page_free((void *)PDE_ADDR(entry));
+ km_page_free((void *)P2V(PDE_ADDR(entry)));
++nt;
*curr = 0;
}
@@ -875,7 +893,8 @@ int vm_uvmdup(pde_t *new, pde_t *old)
if (!IS_LARGE(entry)) {
// it's a 4KB page, so we need to duplicate the PMT
- pte_t *newpt = (pte_t *)vm_pagedup((void *)PTE_ADDR(entry));
+ pte_t *newpt =
+ (pte_t *)vm_pagedup((void *)P2V(PTE_ADDR(entry)));
if (newpt == NULL) {
return E_NO_MEMORY;
}
@@ -883,7 +902,7 @@ int vm_uvmdup(pde_t *new, pde_t *old)
uint32_t perms = PERMS(entry);
// create the new PDE entry by replacing the frame #
- entry = ((uint32_t)newpt) | perms;
+ entry = ((uint32_t)V2P(PTE_ADDR(newpt))) | perms;
}
} else {
@@ -919,8 +938,8 @@ void vm_print(void *pt, bool_t dir, enum vmmode_e mode)
return;
}
- cio_printf("Starting at 0x%08x (%s):\n", (uint32_t)pt,
+ cio_printf(", starting at 0x%08x (%s):\n", (uint32_t)pt,
dir ? "PDIR" : "PMT");
- pdump(0, pt, dir, mode);
+ ptdump(1, pt, dir, mode);
}
generated by cgit v1.2.3-freya (git 2.51.0) at 2025-09-22 23:35:52 +0000