diff options
Diffstat (limited to 'src/kernel')
-rw-r--r-- | src/kernel/handle.c | 25 | ||||
-rw-r--r-- | src/kernel/handle.h | 1 | ||||
-rw-r--r-- | src/kernel/mem/alloc.c | 2 | ||||
-rw-r--r-- | src/kernel/proc.c | 12 | ||||
-rw-r--r-- | src/kernel/syscalls.c | 4 | ||||
-rw-r--r-- | src/kernel/vfs/mount.c | 3 | ||||
-rw-r--r-- | src/kernel/vfs/request.c | 17 | ||||
-rw-r--r-- | src/kernel/vfs/request.h | 10 |
8 files changed, 60 insertions, 14 deletions
diff --git a/src/kernel/handle.c b/src/kernel/handle.c index 91832a0..f5255c0 100644 --- a/src/kernel/handle.c +++ b/src/kernel/handle.c @@ -16,19 +16,22 @@ void handle_close(struct handle *h) { assert(h->refcount > 0); if (--(h->refcount) > 0) return; - if (h->type == HANDLE_FILE) { - vfs_request_create((struct vfs_request) { - .type = VFSOP_CLOSE, - .id = h->file.id, - .caller = NULL, - .backend = h->file.backend, - }); + switch (h->type) { + case HANDLE_FILE: + vfs_request_create((struct vfs_request) { + .type = VFSOP_CLOSE, + .id = h->file.id, + .caller = NULL, + .backend = h->file.backend, + }); + vfs_backend_refdown(h->file.backend); + break; + case HANDLE_FS_FRONT: + vfs_backend_refdown(h->fs.backend); + break; + case HANDLE_INVALID: panic_invalid_state(); } - // TODO handle close(HANDLE_FS_FRONT) - - // TODO count allocations and frees - // TODO sanity check to check if refcount is true. handle_sanity? // TODO tests which would catch premature frees diff --git a/src/kernel/handle.h b/src/kernel/handle.h index df5ad36..3b75894 100644 --- a/src/kernel/handle.h +++ b/src/kernel/handle.h @@ -16,6 +16,7 @@ enum handle_type { struct handle { enum handle_type type; union { + // TODO consolidate backend fields struct { struct vfs_backend *backend; int id; diff --git a/src/kernel/mem/alloc.c b/src/kernel/mem/alloc.c index 0daf935..3925689 100644 --- a/src/kernel/mem/alloc.c +++ b/src/kernel/mem/alloc.c @@ -53,7 +53,7 @@ void mem_debugprint(void) { kprintf("%08x %05x", iter, iter->page_amt); for (size_t i = 0; i < 4; i++) kprintf(" k/%08x", iter->stacktrace[i]); - kprintf("\n"); + kprintf("\n peek 0x%x\n", *(uint32_t*)(&iter[1])); total++; } kprintf(" total 0x%x\n", total); diff --git a/src/kernel/proc.c b/src/kernel/proc.c index 90570b8..40399d8 100644 --- a/src/kernel/proc.c +++ b/src/kernel/proc.c @@ -63,8 +63,10 @@ struct process *process_fork(struct process *parent, int flags) { parent->handled_req = NULL; // TODO control this with a flag - if (child->controlled) + if (child->controlled) { child->controlled->potential_handlers++; + child->controlled->refcount++; + } for (handle_t h = 0; h < HANDLE_MAX; h++) { if (child->handles[h]) @@ -111,6 +113,11 @@ void process_free(struct process *p) { vfs_mount_remref(p->mount); p->mount = NULL; + if (p->controlled) { + vfs_backend_refdown(p->controlled); + p->controlled = NULL; + } + if (!p->parent) return; process_forget(p); pagedir_free(p->pages); // TODO could be done on kill @@ -273,11 +280,14 @@ void process_kill(struct process *p, int ret) { vfs_request_cancel(q, ret); q = q2; } + p->controlled->queue = NULL; } if (p->controlled->handler == p) { assert(p->state == PS_WAITS4REQUEST); p->controlled->handler = NULL; } + + vfs_backend_refdown(p->controlled); p->controlled = NULL; } diff --git a/src/kernel/syscalls.c b/src/kernel/syscalls.c index 7748bc5..ca717ae 100644 --- a/src/kernel/syscalls.c +++ b/src/kernel/syscalls.c @@ -106,6 +106,7 @@ int _syscall_mount(handle_t hid, const char __user *path, int len) { struct handle *handle = process_handle_get(process_current, hid, HANDLE_FS_FRONT); if (!handle) goto fail; backend = handle->fs.backend; + backend->refcount++; } // otherwise backend == NULL // append to mount list @@ -177,15 +178,16 @@ handle_t _syscall_fs_fork2(void) { front = process_find_handle(process_current, 1); if (front < 0) return -1; process_current->handles[front] = handle_init(HANDLE_FS_FRONT); - process_current->handles[front]->type = HANDLE_FS_FRONT; backend = kmalloc(sizeof *backend); // TODO never freed backend->type = VFS_BACK_USER; backend->potential_handlers = 1; + backend->refcount = 2; // child + handle backend->handler = NULL; backend->queue = NULL; child = process_fork(process_current, 0); + if (child->controlled) vfs_backend_refdown(child->controlled); child->controlled = backend; regs_savereturn(&child->regs, 0); diff --git a/src/kernel/vfs/mount.c b/src/kernel/vfs/mount.c index 3fe192d..d13c3d6 100644 --- a/src/kernel/vfs/mount.c +++ b/src/kernel/vfs/mount.c @@ -8,6 +8,7 @@ struct vfs_mount *vfs_mount_seed(void) { struct vfs_backend *backend = kmalloc(sizeof *backend); backend->type = VFS_BACK_ROOT; backend->potential_handlers = 1; + backend->refcount = 1; *mount = (struct vfs_mount){ .prev = NULL, .prefix = NULL, @@ -45,6 +46,8 @@ void vfs_mount_remref(struct vfs_mount *mnt) { if (--(mnt->refs) > 0) return; struct vfs_mount *prev = mnt->prev; + if (mnt->backend) + vfs_backend_refdown(mnt->backend); kfree(mnt->prefix); kfree(mnt); diff --git a/src/kernel/vfs/request.c b/src/kernel/vfs/request.c index 1f3193f..edb1fce 100644 --- a/src/kernel/vfs/request.c +++ b/src/kernel/vfs/request.c @@ -11,6 +11,9 @@ int vfs_request_create(struct vfs_request req_) { memcpy(req, &req_, sizeof *req); /* freed in vfs_request_finish or vfs_request_cancel */ + if (req->backend) + req->backend->refcount++; + if (req->caller) { process_transition(req->caller, PS_WAITS4FS); req->caller->waits4fs.req = req; @@ -87,6 +90,7 @@ int vfs_request_finish(struct vfs_request *req, int ret) { struct handle *backing = handle_init(HANDLE_FILE); backing->file.backend = req->backend; + req->backend->refcount++; backing->file.id = ret; req->caller->handles[handle] = backing; ret = handle; @@ -101,11 +105,13 @@ int vfs_request_finish(struct vfs_request *req, int ret) { process_transition(req->caller, PS_RUNNING); } + vfs_backend_refdown(req->backend); kfree(req); return ret; } void vfs_request_cancel(struct vfs_request *req, int ret) { + // TODO merge with vfs_request_finish if (req->caller) { assert(req->caller->state == PS_WAITS4FS); @@ -118,5 +124,16 @@ void vfs_request_cancel(struct vfs_request *req, int ret) { regs_savereturn(&req->caller->regs, ret); process_transition(req->caller, PS_RUNNING); } + + vfs_backend_refdown(req->backend); kfree(req); } + +void vfs_backend_refdown(struct vfs_backend *b) { + assert(b); + assert(b->refcount > 0); + if (--(b->refcount) > 0) return; + + assert(!b->queue); + kfree(b); +} diff --git a/src/kernel/vfs/request.h b/src/kernel/vfs/request.h index 657ae85..69dad07 100644 --- a/src/kernel/vfs/request.h +++ b/src/kernel/vfs/request.h @@ -11,6 +11,14 @@ enum vfs_backend_type { // describes something which can act as an access function struct vfs_backend { + size_t refcount; + /* references: + * struct vfs_mount + * struct vfs_request + * struct process + * struct handle + */ + enum vfs_backend_type type; size_t potential_handlers; // 0 - orphaned @@ -52,3 +60,5 @@ int vfs_backend_accept(struct vfs_backend *); int vfs_request_finish(struct vfs_request *, int ret); void vfs_request_cancel(struct vfs_request *, int ret); + +void vfs_backend_refdown(struct vfs_backend *); |