#include <arch/arch.h>
#include <arch/mmu.h>
+#include <bitmask.h>
#include <elf.h>
#include <smp.h>
-
#include <atomic.h>
#include <string.h>
#include <assert.h>
#include <manager.h>
#include <stdio.h>
#include <schedule.h>
+#include <kmalloc.h>
+#include <mm.h>
#include <ros/syscall.h>
-#include <ros/error.h>
+#include <error.h>
-env_t *envs = NULL; // All environments
atomic_t num_envs;
-// TODO: make this a struct of info including the pointer and cacheline-align it
-// This lets the kernel know what process is running on the core it traps into.
-// A lot of the Env business, including this and its usage, will change when we
-// redesign the env as a multi-process.
-env_t* curenvs[MAX_NUM_CPUS] = {[0 ... (MAX_NUM_CPUS-1)] NULL};
-
-#define ENVGENSHIFT 12 // >= LOGNENV
-
-//
-// Converts an envid to an env pointer.
-//
-// RETURNS
-// 0 on success, -EBADENV on error.
-// On success, sets *env_store to the environment.
-// On error, sets *env_store to NULL.
-//
-int
-envid2env(envid_t envid, env_t **env_store, bool checkperm)
-{
- env_t *e;
-
- // If envid is zero, return the current environment.
- if (envid == 0) {
- *env_store = current;
- return 0;
- }
-
- // Look up the Env structure via the index part of the envid,
- // then check the env_id field in that env_t
- // to ensure that the envid is not stale
- // (i.e., does not refer to a _previous_ environment
- // that used the same slot in the envs[] array).
- e = &envs[ENVX(envid)];
- if (e->state == ENV_FREE || e->env_id != envid) {
- *env_store = 0;
- return -EBADENV;
- }
- // Check that the calling environment has legitimate permission
- // to manipulate the specified environment.
- // If checkperm is set, the specified environment
- // must be either the current environment
- // or an immediate child of the current environment.
- // TODO: should check for current being null
- if (checkperm && e != current && e->env_parent_id != current->env_id) {
- *env_store = 0;
- return -EBADENV;
- }
-
- *env_store = e;
- return 0;
-}
-
-//
-// Mark all environments in 'envs' as free, set their env_ids to 0,
-// and insert them into the proc_freelist.
-// Insert in reverse order, so that the first call to env_alloc()
-// returns envs[0].
-// TODO: get rid of this whole array bullshit
-//
-void
-env_init(void)
-{
- int i;
-
- schedule_init();
- atomic_init(&num_envs, 0);
- TAILQ_INIT(&proc_freelist);
- assert(envs != NULL);
- for (i = NENV-1; i >= 0; i--) {
- // these should already be set from when i memset'd the array to 0
- envs[i].state = ENV_FREE;
- envs[i].env_id = 0;
- TAILQ_INSERT_HEAD(&proc_freelist, &envs[i], proc_link);
- }
-
-}
-
-//
// Initialize the kernel virtual memory layout for environment e.
// Allocate a page directory, set e->env_pgdir and e->env_cr3 accordingly,
// and initialize the kernel portion of the new environment's address space.
// Returns 0 on success, < 0 on error. Errors include:
// -ENOMEM if page directory or table could not be allocated.
//
-static int
-env_setup_vm(env_t *e)
-WRITES(e->env_pgdir, e->env_cr3, e->env_procinfo, e->env_procdata)
+int env_setup_vm(env_t *e)
+WRITES(e->env_pgdir, e->env_cr3, e->procinfo, e->procdata)
{
int i, r;
page_t *pgdir = NULL;
- page_t *pginfo[PROCINFO_NUM_PAGES] = {NULL};
- page_t *pgdata[PROCDATA_NUM_PAGES] = {NULL};
- static page_t* shared_page = 0;
+ static page_t * RO shared_page = 0;
- /*
- * First, allocate a page for the pgdir of this process and up
- * its reference count since this will never be done elsewhere
- */
- r = page_alloc(&pgdir);
- if(r < 0) return r;
- page_incref(pgdir);
+ /* Get a page for the pgdir. Storing the ref in pgdir/env_pgdir */
+ r = kpage_alloc(&pgdir);
+ if (r < 0)
+ return r;
/*
* Next, set up the e->env_pgdir and e->env_cr3 pointers to point
// Map in the kernel to the top of every address space
// should be able to do this so long as boot_pgdir never has
- // anything put below UTOP
+ // anything put below ULIM
// TODO check on this! had a nasty bug because of it
// this is a bit wonky, since if it's not PGSIZE, lots of other things are
// screwed up...
// VPT and UVPT map the env's own page table, with
// different permissions.
- e->env_pgdir[PDX(VPT)] = PTE(PPN(e->env_cr3), PTE_P | PTE_KERN_RW);
- e->env_pgdir[PDX(UVPT)] = PTE(PPN(e->env_cr3), PTE_P | PTE_USER_RO);
-
- /*
- * Now allocate and insert all pages required for the shared
- * procinfo structure into the page table
- */
- for(int i=0; i<PROCINFO_NUM_PAGES; i++) {
- if(page_alloc(&pginfo[i]) < 0)
- goto env_setup_vm_error;
- if(page_insert(e->env_pgdir, pginfo[i], (void*SNT)(UINFO + i*PGSIZE),
- PTE_USER_RO) < 0)
+ #ifndef NOVPT
+ e->env_pgdir[PDX(VPT)] = PTE(LA2PPN(e->env_cr3), PTE_P | PTE_KERN_RW);
+ e->env_pgdir[PDX(UVPT)] = PTE(LA2PPN(e->env_cr3), PTE_P | PTE_USER_RO);
+ #endif
+
+ /* These need to be contiguous, so the kernel can alias them. Note the
+ * pages return with a refcnt, but it's okay to insert them since we free
+ * them manually when the process is cleaned up. */
+ if (!(e->procinfo = get_cont_pages(LOG2_UP(PROCINFO_NUM_PAGES), 0)))
+ goto env_setup_vm_error_i;
+ if (!(e->procdata = get_cont_pages(LOG2_UP(PROCDATA_NUM_PAGES), 0)))
+ goto env_setup_vm_error_d;
+ /* Normally we'd 0 the pages here. We handle it in proc_init_proc*. Don't
+ * start the process without calling those. */
+ for (int i = 0; i < PROCINFO_NUM_PAGES; i++) {
+ if (page_insert(e->env_pgdir, kva2page((void*)e->procinfo + i *
+ PGSIZE), (void*SNT)(UINFO + i*PGSIZE), PTE_USER_RO) < 0)
goto env_setup_vm_error;
}
-
- /*
- * Now allocate and insert all pages required for the shared
- * procdata structure into the page table
- */
- for(int i=0; i<PROCDATA_NUM_PAGES; i++) {
- if(page_alloc(&pgdata[i]) < 0)
- goto env_setup_vm_error;
- if(page_insert(e->env_pgdir, pgdata[i], (void*SNT)(UDATA + i*PGSIZE),
- PTE_USER_RW) < 0)
+ for (int i = 0; i < PROCDATA_NUM_PAGES; i++) {
+ if (page_insert(e->env_pgdir, kva2page((void*)e->procdata + i *
+ PGSIZE), (void*SNT)(UDATA + i*PGSIZE), PTE_USER_RW) < 0)
goto env_setup_vm_error;
}
-
- /*
- * Now, set e->env_procinfo, and e->env_procdata to point to
- * the proper pages just allocated and clear them out.
- */
- e->env_procinfo = (procinfo_t *SAFE) TC(page2kva(pginfo[0]));
- e->env_procdata = (procdata_t *SAFE) TC(page2kva(pgdata[0]));
-
- memset(e->env_procinfo, 0, sizeof(procinfo_t));
- memset(e->env_procdata, 0, sizeof(procdata_t));
-
- /* Finally, set up the Global Shared Data page for all processes.
- * Can't be trusted, but still very useful at this stage for us.
- * Consider removing when we have real processes.
- * (TODO). Note the page is alloced only the first time through
- */
+ /* Finally, set up the Global Shared Data page for all processes. Can't be
+ * trusted, but still very useful at this stage for us. Consider removing
+ * when we have real processes (TODO).
+ *
+ * Note the page is alloced only the first time through, and its ref is
+ * stored in shared_page. */
if (!shared_page) {
- if(page_alloc(&shared_page) < 0)
+ if (upage_alloc(e, &shared_page, 1) < 0)
goto env_setup_vm_error;
- // Up it, so it never goes away. One per user, plus one from page_alloc
- // This is necessary, since it's in the per-process range of memory that
- // gets freed during page_free.
- page_incref(shared_page);
}
-
- // Inserted into every process's address space at UGDATA
- if(page_insert(e->env_pgdir, shared_page, (void*SNT)UGDATA, PTE_USER_RW) < 0)
+ if (page_insert(e->env_pgdir, shared_page, (void*)UGDATA, PTE_USER_RW) < 0)
goto env_setup_vm_error;
return 0;
env_setup_vm_error:
- page_free(shared_page);
- for(int i=0; i< PROCDATA_NUM_PAGES; i++) {
- page_free(pgdata[i]);
- }
- for(int i=0; i< PROCINFO_NUM_PAGES; i++) {
- page_free(pginfo[i]);
- }
- env_user_mem_free(e);
- page_free(pgdir);
+ free_cont_pages(e->procdata, LOG2_UP(PROCDATA_NUM_PAGES));
+env_setup_vm_error_d:
+ free_cont_pages(e->procinfo, LOG2_UP(PROCINFO_NUM_PAGES));
+env_setup_vm_error_i:
+ page_decref(shared_page);
+ env_user_mem_free(e, 0, UVPT);
+ env_pagetable_free(e);
return -ENOMEM;
}
-//
-// Allocates and initializes a new environment.
-// On success, the new environment is stored in *newenv_store.
-//
-// Returns 0 on success, < 0 on failure. Errors include:
-// -ENOFREEENV if all NENVS environments are allocated
-// -ENOMEM on memory exhaustion
-//
-int
-env_alloc(env_t **newenv_store, envid_t parent_id)
-{
- int32_t generation;
- int r;
- env_t *e;
-
- spin_lock(&freelist_lock);
- e = TAILQ_FIRST(&proc_freelist);
- if (e) {
- TAILQ_REMOVE(&proc_freelist, e, proc_link);
- spin_unlock(&freelist_lock);
- } else {
- spin_unlock(&freelist_lock);
- return -ENOFREEENV;
- }
-
- { INITSTRUCT(*e)
-
- // Allocate and set up the page directory for this environment.
- if ((r = env_setup_vm(e)) < 0) {
- spin_lock(&freelist_lock);
- TAILQ_INSERT_HEAD(&proc_freelist, e, proc_link);
- spin_unlock(&freelist_lock);
- return r;
- }
-
- // Generate an env_id for this environment.
- generation = (e->env_id + (1 << ENVGENSHIFT)) & ~(NENV - 1);
- if (generation <= 0) // Don't create a negative env_id.
- generation = 1 << ENVGENSHIFT;
- e->env_id = generation | (e - envs);
-
- // Set the basic status variables.
- e->proc_lock = 0;
- e->env_parent_id = parent_id;
- proc_set_state(e, PROC_CREATED);
- e->env_runs = 0;
- e->env_refcnt = 1;
- e->env_flags = 0;
- e->env_entry = 0; // cheating. this really gets set in load_icode
-#ifdef __SHARC__
- /* init SharC state */
- sharC_env_init(&e->sharC_env);
-#endif
- e->num_vcores = 0; // only used in RUNN*_M states
- memset(&e->vcoremap, 0, sizeof(e->vcoremap));
-
- memset(&e->env_ancillary_state, 0, sizeof(e->env_ancillary_state));
- memset(&e->env_tf, 0, sizeof(e->env_tf));
- env_init_trapframe(&e->env_tf);
-
- /*
- * Initialize the contents of the e->env_procinfo structure
- */
- e->env_procinfo->id = (e->env_id & 0x3FF);
-
- /*
- * Initialize the contents of the e->env_procdata structure
- */
- // Initialize the generic syscall ring buffer
- SHARED_RING_INIT(&e->env_procdata->syscallring);
- // Initialize the backend of the syscall ring buffer
- BACK_RING_INIT(&e->syscallbackring,
- &e->env_procdata->syscallring,
- SYSCALLRINGSIZE);
-
- // Initialize the generic sysevent ring buffer
- SHARED_RING_INIT(&e->env_procdata->syseventring);
- // Initialize the frontend of the sysevent ring buffer
- FRONT_RING_INIT(&e->syseventfrontring,
- &e->env_procdata->syseventring,
- SYSEVENTRINGSIZE);
-
- *newenv_store = e;
- atomic_inc(&num_envs);
-
- printk("[%08x] new env %08x\n", current ? current->env_id : 0, e->env_id);
- } // INIT_STRUCT
- return 0;
-}
-
-//
-// Allocate len bytes of physical memory for environment env,
-// and map it at virtual address va in the environment's address space.
-// Does not zero or otherwise initialize the mapped pages in any way.
-// Pages should be writable by user and kernel.
-// Panic if any allocation attempt fails.
-//
-static void
-segment_alloc(env_t *e, void *SNT va, size_t len)
-{
- void *SNT start, *SNT end;
- size_t num_pages;
- int i, r;
- page_t *page;
- pte_t *pte;
-
- start = ROUNDDOWN(va, PGSIZE);
- end = ROUNDUP(va + len, PGSIZE);
- if (start >= end)
- panic("Wrap-around in memory allocation addresses!");
- if ((uintptr_t)end > UTOP)
- panic("Attempting to map above UTOP!");
- // page_insert/pgdir_walk alloc a page and read/write to it via its address
- // starting from pgdir (e's), so we need to be using e's pgdir
- assert(e->env_cr3 == rcr3());
- num_pages = PPN(end - start);
-
- for (i = 0; i < num_pages; i++, start += PGSIZE) {
- // skip if a page is already mapped. yes, page_insert will page_remove
- // whatever page was already there, but if we are seg allocing adjacent
- // regions, we don't want to destroy that old mapping/page
- // though later on we are told we can ignore this...
- pte = pgdir_walk(e->env_pgdir, start, 0);
- if (pte && *pte & PTE_P)
- continue;
- if ((r = page_alloc(&page)) < 0)
- panic("segment_alloc: %e", r);
- page_insert(e->env_pgdir, page, start, PTE_USER_RW);
- }
-}
-
-//
-// Set up the initial program binary, stack, and processor flags
-// for a user process.
-//
-// This function loads all loadable segments from the ELF binary image
-// into the environment's user memory, starting at the appropriate
-// virtual addresses indicated in the ELF program header.
-// At the same time it clears to zero any portions of these segments
-// that are marked in the program header as being mapped
-// but not actually present in the ELF file - i.e., the program's bss section.
-//
-// Finally, this function maps one page for the program's initial stack.
-static void
-load_icode(env_t *SAFE e, uint8_t *COUNT(size) binary, size_t size)
-{
- // asw: copy the headers because they might not be aligned.
- elf_t elfhdr;
- proghdr_t phdr;
- memcpy(&elfhdr, binary, sizeof(elfhdr));
-
- int i, r;
-
- // is this an elf?
- assert(elfhdr.e_magic == ELF_MAGIC);
- // make sure we have proghdrs to load
- assert(elfhdr.e_phnum);
-
- // to actually access any pages alloc'd for this environment, we
- // need to have the hardware use this environment's page tables.
- uintreg_t old_cr3 = rcr3();
- /*
- * Even though we'll decref later and no one should be killing us at this
- * stage, we're still going to wrap the lcr3s with incref/decref.
- *
- * Note we never decref on the old_cr3, since we aren't willing to let it
- * die. It's also not clear who the previous process is - sometimes it
- * isn't even a process (when the kernel loads on its own, and not in
- * response to a syscall). Probably need to think more about this (TODO)
- *
- * This can get a bit tricky if this code blocks (will need to think about a
- * decref then), if we try to change states, etc.
- */
- proc_incref(e);
- lcr3(e->env_cr3);
-
- // TODO: how do we do a runtime COUNT?
- {TRUSTEDBLOCK // zra: TRUSTEDBLOCK until validation is done.
- for (i = 0; i < elfhdr.e_phnum; i++) {
- memcpy(&phdr, binary + elfhdr.e_phoff + i*sizeof(phdr), sizeof(phdr));
- if (phdr.p_type != ELF_PROG_LOAD)
- continue;
- // TODO: validate elf header fields!
- // seg alloc creates PTE_U|PTE_W pages. if you ever want to change
- // this, there will be issues with overlapping sections
- segment_alloc(e, (void*SNT)phdr.p_va, phdr.p_memsz);
- memcpy((void*)phdr.p_va, binary + phdr.p_offset, phdr.p_filesz);
- memset((void*)phdr.p_va + phdr.p_filesz, 0, phdr.p_memsz - phdr.p_filesz);
- }}
-
- env_set_program_counter(e, elfhdr.e_entry);
- e->env_entry = elfhdr.e_entry;
-
- // Now map one page for the program's initial stack
- // at virtual address USTACKTOP - PGSIZE.
- segment_alloc(e, (void*SNT)(USTACKTOP - PGSIZE), PGSIZE);
-
- // reload the original address space
- lcr3(old_cr3);
- proc_decref(e);
-}
-
-//
-// Allocates a new env and loads the named elf binary into it.
-//
-env_t* env_create(uint8_t *binary, size_t size)
-{
- env_t *e;
- int r;
- envid_t curid;
-
- curid = (current ? current->env_id : 0);
- if ((r = env_alloc(&e, curid)) < 0)
- panic("env_create: %e", r);
- load_icode(e, binary, size);
- return e;
-}
-
-//
-// Frees env e and all memory it uses.
-//
-void
-env_free(env_t *e)
-{
- physaddr_t pa;
-
- // Note the environment's demise.
- printk("[%08x] free env %08x\n", current ? current->env_id : 0, e->env_id);
- // All parts of the kernel should have decref'd before env_free was called.
- assert(e->env_refcnt == 0);
-
- // Flush all mapped pages in the user portion of the address space
- env_user_mem_free(e);
-
- // free the page directory
- pa = e->env_cr3;
- e->env_pgdir = 0;
- e->env_cr3 = 0;
- page_decref(pa2page(pa));
-
- // return the environment to the free list
- e->state = ENV_FREE;
- TAILQ_INSERT_HEAD(&proc_freelist, e, proc_link);
-}
-
-
#define PER_CPU_THING(type,name)\
type SLOCKED(name##_lock) * RWPROTECT name;\
type SLOCKED(name##_lock) *\
}\
}
-
-/* This is the top-half of an interrupt handler, where the bottom half is
- * proc_run (which never returns). Just add it to the delayed work queue,
- * which (incidentally) can only hold one item at this point.
- *
- * Note this is rather old, and meant to run a RUNNABLE_S on a worker core.
- */
-void run_env_handler(trapframe_t *tf, env_t *data)
+/* Frees (decrefs) all memory mapped in the given range */
+void env_user_mem_free(env_t* e, void* start, size_t len)
{
- assert(data);
- struct work TP(env_t *) job;
- struct workqueue *workqueue = &per_cpu_info[core_id()].workqueue;
+ assert((uintptr_t)start + len <= UVPT); //since this keeps fucking happening
+ int user_page_free(env_t* e, pte_t* pte, void* va, void* arg)
{
- job.func = proc_run;
- job.data = data;
+ if (!PAGE_PRESENT(*pte))
+ return 0;
+ page_t *page = ppn2page(PTE2PPN(*pte));
+ *pte = 0;
+ page_decref(page);
+ /* TODO: consider other states here (like !P, yet still tracking a page,
+ * for VM tricks, page map stuff, etc. Should be okay: once we're
+ * freeing, everything else about this proc is dead. */
+ return 0;
}
- if (enqueue_work(workqueue, &job))
- panic("Failed to enqueue work!");
+
+ env_user_mem_walk(e,start,len,&user_page_free,NULL);
+ tlbflush();
}
+
projects / akaros.git / blobdiff