diff options
| -rw-r--r-- | kernel/user.c | 60 |
1 files changed, 41 insertions, 19 deletions
diff --git a/kernel/user.c b/kernel/user.c index b4f10d5..9d933e5 100644 --- a/kernel/user.c +++ b/kernel/user.c @@ -13,43 +13,61 @@ #define USER_STACK_TOP 0x800000000000 #define USER_STACK_LEN (4 * PAGE_SIZE) +#define BLOCK_SIZE (PAGE_SIZE * 1000) +static uint8_t *load_buffer = NULL; + static int user_load_segment(struct pcb *pcb, struct disk *disk, int idx) { - uint8_t buf[PAGE_SIZE]; Elf64_Phdr hdr; - size_t npages, nvpages, nbytes; + size_t mem_bytes, mem_pages; + size_t file_bytes, file_pages; + uint8_t *mapADDR; hdr = pcb->elf_segments[idx]; - nbytes = hdr.p_filesz; - npages = (nbytes + PAGE_SIZE - 1) / PAGE_SIZE; - nvpages = (hdr.p_memsz + PAGE_SIZE - 1) / PAGE_SIZE; - if (npages < 1) + // return if this is not a lodable segment + if (hdr.p_type != PT_LOAD) return 0; - if (hdr.p_type != PT_LOAD) + mem_bytes = hdr.p_memsz; + file_bytes = hdr.p_filesz; + + // we cannot read more data to less memory + if (file_bytes > mem_bytes) + return 1; + + mem_pages = (mem_bytes + PAGE_SIZE - 1) / PAGE_SIZE; + file_pages = (file_bytes + PAGE_SIZE - 1) / PAGE_SIZE; + + // return if were reading no data + if (file_pages < 1) return 0; // allocate memory in user process - if (mem_alloc_pages_at(pcb->memctx, nvpages, (void *)hdr.p_vaddr, + if (mem_alloc_pages_at(pcb->memctx, mem_pages, (void *)hdr.p_vaddr, F_WRITEABLE | F_UNPRIVILEGED) == NULL) return 1; + mapADDR = kmapuseraddr(pcb->memctx, (void *)hdr.p_vaddr, mem_bytes); + if (mapADDR == NULL) + return 1; + // load data - for (size_t i = 0; i < npages && nbytes; i++) { - size_t bytes = PAGE_SIZE; - if (nbytes < bytes) - bytes = nbytes; - mem_ctx_switch(kernel_mem_ctx); // disk_read is kernel internal - memset(buf + bytes, 0, PAGE_SIZE - bytes); - if (disk_read(disk, hdr.p_offset + i * PAGE_SIZE, bytes, buf)) + size_t total_read = 0; + while (total_read < file_bytes) { + 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) { + kunmapaddr(mapADDR); return 1; - mem_ctx_switch(pcb->memctx); - memcpy((char *)hdr.p_vaddr + i * PAGE_SIZE, buf, bytes); - nbytes -= bytes; + } + memcpyv(mapADDR + total_read, load_buffer, read); + total_read += read; } - mem_ctx_switch(kernel_mem_ctx); + kunmapaddr(mapADDR); return 0; } @@ -57,6 +75,10 @@ static int user_load_segments(struct pcb *pcb, struct disk *disk) { int ret = 0; + if (load_buffer == NULL) + if ((load_buffer = kalloc(BLOCK_SIZE)) == NULL) + return 1; + for (int i = 0; i < pcb->n_elf_segments; i++) if ((ret = user_load_segment(pcb, disk, i))) return ret; |