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Diffstat (limited to 'kernel/user.c')
-rw-r--r--kernel/user.c136
1 files changed, 105 insertions, 31 deletions
diff --git a/kernel/user.c b/kernel/user.c
index e22248a..27b46df 100644
--- a/kernel/user.c
+++ b/kernel/user.c
@@ -1,3 +1,4 @@
+#include "lib/kio.h"
#include <comus/fs.h>
#include <comus/procs.h>
#include <comus/memory.h>
@@ -20,7 +21,7 @@ static uint8_t *load_buffer = NULL;
#define USER_DATA 0x20
#define RING3 3
-static int user_load_segment(struct pcb *pcb, struct disk *disk, int idx)
+static int user_load_segment(struct pcb *pcb, struct file *file, int idx)
{
Elf64_Phdr hdr;
size_t mem_bytes, mem_pages;
@@ -49,12 +50,22 @@ static int user_load_segment(struct pcb *pcb, struct disk *disk, int idx)
// allocate memory in user process
if (mem_alloc_pages_at(pcb->memctx, mem_pages, (void *)hdr.p_vaddr,
- F_WRITEABLE | F_UNPRIVILEGED) == NULL)
+ F_WRITEABLE | F_UNPRIVILEGED) == NULL) {
+ ERROR("Could not allocate memory for elf segment");
return 1;
+ }
mapADDR = kmapuseraddr(pcb->memctx, (void *)hdr.p_vaddr, mem_bytes);
- if (mapADDR == NULL)
+ if (mapADDR == NULL) {
+ ERROR("Could load memory for elf segment");
return 1;
+ }
+
+ // seek to start of segment
+ if (file->seek(file, hdr.p_offset, SEEK_SET) < 0) {
+ ERROR("Could not load elf segment");
+ return 1;
+ }
// load data
size_t total_read = 0;
@@ -62,12 +73,14 @@ static int user_load_segment(struct pcb *pcb, struct disk *disk, int idx)
size_t read = BLOCK_SIZE;
if (read > file_bytes - total_read)
read = file_bytes - total_read;
- if ((read = disk_read(disk, hdr.p_offset + total_read, read,
- load_buffer)) < 1) {
+ TRACE("Reading %zu bytes...", read);
+ if ((read = file->read(file, load_buffer, read)) < 1) {
kunmapaddr(mapADDR);
+ ERROR("Could not load elf segment");
return 1;
}
- memcpy(mapADDR + total_read, load_buffer, read);
+ TRACE("Read %zu bytes", read);
+ memcpyv(mapADDR + total_read, load_buffer, read);
total_read += read;
}
@@ -79,19 +92,24 @@ static int user_load_segment(struct pcb *pcb, struct disk *disk, int idx)
return 0;
}
-static int user_load_segments(struct pcb *pcb, struct disk *disk)
+static int user_load_segments(struct pcb *pcb, struct file *file)
{
int ret = 0;
pcb->heap_start = NULL;
pcb->heap_len = 0;
- if (load_buffer == NULL)
- if ((load_buffer = kalloc(BLOCK_SIZE)) == NULL)
+ if (load_buffer == NULL) {
+ load_buffer = kalloc(BLOCK_SIZE);
+ if (load_buffer == NULL) {
+ ERROR("Could not allocate user load buffer");
return 1;
+ }
+ }
+ TRACE("Loading %u elf segments", pcb->n_elf_segments);
for (int i = 0; i < pcb->n_elf_segments; i++)
- if ((ret = user_load_segment(pcb, disk, i)))
+ if ((ret = user_load_segment(pcb, file, i)))
return ret;
if (pcb->heap_start == NULL) {
@@ -107,12 +125,12 @@ static int validate_elf_hdr(struct pcb *pcb)
Elf64_Ehdr *ehdr = &pcb->elf_header;
if (strncmp((const char *)ehdr->e_ident, ELFMAG, SELFMAG)) {
- WARN("Invalid ELF File.");
+ ERROR("Invalid ELF File.");
return 1;
}
if (ehdr->e_ident[EI_CLASS] != ELFCLASS64) {
- WARN("Unsupported ELF Class.");
+ ERROR("Unsupported ELF Class.");
return 1;
}
@@ -122,17 +140,17 @@ static int validate_elf_hdr(struct pcb *pcb)
}
if (ehdr->e_machine != EM_X86_64) {
- WARN("Unsupported ELF File target.");
+ ERROR("Unsupported ELF File target.");
return 1;
}
if (ehdr->e_ident[EI_VERSION] != EV_CURRENT) {
- WARN("Unsupported ELF File version.");
+ ERROR("Unsupported ELF File version.");
return 1;
}
if (ehdr->e_phnum > N_ELF_SEGMENTS) {
- WARN("Too many ELF segments.");
+ ERROR("Too many ELF segments.");
return 1;
}
@@ -144,35 +162,90 @@ static int validate_elf_hdr(struct pcb *pcb)
return 0;
}
-static int user_load_elf(struct pcb *pcb, struct disk *disk)
+static int user_load_elf(struct pcb *pcb, struct file *file)
{
int ret = 0;
- ret = disk_read(disk, 0, sizeof(Elf64_Ehdr), &pcb->elf_header);
- if (ret < 0)
+ if (file->seek(file, 0, SEEK_SET) < 0) {
+ ERROR("Cannot read ELF header.");
return 1;
+ }
+ ret = file->read(file, &pcb->elf_header, sizeof(Elf64_Ehdr));
+ if (ret < 0) {
+ ERROR("Cannot read ELF header.");
+ return 1;
+ }
if (validate_elf_hdr(pcb))
return 1;
pcb->n_elf_segments = pcb->elf_header.e_phnum;
- ret = disk_read(disk, pcb->elf_header.e_phoff,
- sizeof(Elf64_Phdr) * pcb->elf_header.e_phnum,
- &pcb->elf_segments);
- if (ret < 0)
+ if (file->seek(file, pcb->elf_header.e_phoff, SEEK_SET) < 0) {
+ ERROR("Cannot read ELF segemts");
return 1;
+ }
+ ret = file->read(file, &pcb->elf_segments,
+ sizeof(Elf64_Phdr) * pcb->elf_header.e_phnum);
+ if (ret < 0) {
+ ERROR("Cannot read ELF segemts");
+ return 1;
+ }
return 0;
}
-static int user_setup_stack(struct pcb *pcb)
+static int user_setup_stack(struct pcb *pcb, const char **args,
+ mem_ctx_t args_ctx)
{
- // allocate stack
+ /* args */
+ int argbytes = 0;
+ int argc = 0;
+
+ mem_ctx_switch(args_ctx);
+
+ while (args[argc] != NULL) {
+ int n = strlen(args[argc]) + 1;
+ if ((argbytes + n) > USER_STACK_LEN) {
+ // oops - ignore this and any others
+ break;
+ }
+ argbytes += n;
+ argc++;
+ }
+
+ // round to nearest multiple of 8
+ argbytes = (argbytes + 7) & 0xfffffffffffffff8;
+
+ // allocate arg strings on kernel stack
+ char argstrings[argbytes];
+ char *argv[argc + 1];
+ memset(argstrings, 0, sizeof(argstrings));
+ memset(argv, 0, sizeof(argv));
+
+ // Next, duplicate the argument strings, and create pointers to
+ // each one in our argv.
+ char *tmp = argstrings;
+ for (int i = 0; i < argc; ++i) {
+ int nb = strlen(args[i]) + 1;
+ strcpy(tmp, args[i]);
+ argv[i] = tmp;
+ tmp += nb;
+ }
+
+ // trailing NULL pointer
+ argv[argc] = NULL;
+
+ mem_ctx_switch(kernel_mem_ctx);
+
+ /* stack */
if (mem_alloc_pages_at(pcb->memctx, USER_STACK_LEN / PAGE_SIZE,
(void *)(USER_STACK_TOP - USER_STACK_LEN),
- F_WRITEABLE | F_UNPRIVILEGED) == NULL)
+ F_WRITEABLE | F_UNPRIVILEGED) == NULL) {
+ ERROR("Could not allocate user stack");
return 1;
+ }
+ /* regs */
memset(&pcb->regs, 0, sizeof(struct cpu_regs));
// pgdir
@@ -183,7 +256,7 @@ static int user_setup_stack(struct pcb *pcb)
pcb->regs.es = USER_DATA | RING3;
pcb->regs.ds = USER_DATA | RING3;
// registers
- pcb->regs.rdi = 0; // argc
+ pcb->regs.rdi = argc; // argc
pcb->regs.rsi = 0; // argv
// intruction pointer
pcb->regs.rip = pcb->elf_header.e_entry;
@@ -199,10 +272,11 @@ static int user_setup_stack(struct pcb *pcb)
return 0;
}
-int user_load(struct pcb *pcb, struct disk *disk)
+int user_load(struct pcb *pcb, struct file *file, const char **args,
+ mem_ctx_t args_ctx)
{
// check inputs
- if (pcb == NULL || disk == NULL)
+ if (pcb == NULL || file == NULL)
return 1;
// allocate memory context
@@ -211,15 +285,15 @@ int user_load(struct pcb *pcb, struct disk *disk)
goto fail;
// load elf information
- if (user_load_elf(pcb, disk))
+ if (user_load_elf(pcb, file))
goto fail;
// load segments into memory
- if (user_load_segments(pcb, disk))
+ if (user_load_segments(pcb, file))
goto fail;
// setup process stack
- if (user_setup_stack(pcb))
+ if (user_setup_stack(pcb, args, args_ctx))
goto fail;
// success
generated by cgit v1.2.3-freya (git 2.51.0) at 2025-09-25 23:29:08 +0000