Hi,
        I recently installed linux winex (again) now that I have working
nVidia drivers. However I found that almost nothing worked and there was a
message about mmap2 not being implemented. I implemented it, but I'm not
sure if it's done right... because some things started working after I
implemented it, but a lot of software that is supposed to work with it
still doesn't. For those who don't know, winex is a version of wine that
supports running windows games that require direct3d to work.

Here is my mmap2 implementation, based on the current mmap:

int
linux_mmap2(struct proc *p, struct linux_mmap2_args *linux_args)
{
        struct mmap_args /* {
                caddr_t addr;
                size_t len;
                int prot;
                int flags;
                int fd;
                long pad;
                off_t pos;
        } */ bsd_args;

        bsd_args.flags = 0;
        if (linux_args->flags & LINUX_MAP_SHARED)
                bsd_args.flags |= MAP_SHARED;
        if (linux_args->flags & LINUX_MAP_PRIVATE)
                bsd_args.flags |= MAP_PRIVATE;
        if (linux_args->flags & LINUX_MAP_FIXED)
                bsd_args.flags |= MAP_FIXED;
        if (linux_args->flags & LINUX_MAP_ANON)
                bsd_args.flags |= MAP_ANON;
        else
                bsd_args.flags |= MAP_NOSYNC;
        if (linux_args->flags & LINUX_MAP_GROWSDOWN) {
                bsd_args.flags |= MAP_STACK;

                /* The linux MAP_GROWSDOWN option does not limit auto
                 * growth of the region.  Linux mmap with this option
                 * takes as addr the inital BOS, and as len, the initial
                 * region size.  It can then grow down from addr without
                 * limit.  However, linux threads has an implicit internal
                 * limit to stack size of STACK_SIZE.  Its just not
                 * enforced explicitly in linux.  But, here we impose
                 * a limit of (STACK_SIZE - GUARD_SIZE) on the stack
                 * region, since we can do this with our mmap.
                 *
                 * Our mmap with MAP_STACK takes addr as the maximum
                 * downsize limit on BOS, and as len the max size of
                 * the region.  It them maps the top SGROWSIZ bytes,
                 * and autgrows the region down, up to the limit
                 * in addr.
                 *
                 * If we don't use the MAP_STACK option, the effect
                 * of this code is to allocate a stack region of a
                 * fixed size of (STACK_SIZE - GUARD_SIZE).
                 */

                /* This gives us TOS */
                bsd_args.addr = (caddr_t)(linux_args->addr +
linux_args->len);

                if (bsd_args.addr > p->p_vmspace->vm_maxsaddr) {
                        /* Some linux apps will attempt to mmap
                         * thread stacks near the top of their
                         * address space.  If their TOS is greater
                         * than vm_maxsaddr, vm_map_growstack()
                         * will confuse the thread stack with the
                         * process stack and deliver a SEGV if they
                         * attempt to grow the thread stack past their
                         * current stacksize rlimit.  To avoid this,
                         * adjust vm_maxsaddr upwards to reflect
                         * the current stacksize rlimit rather
                         * than the maximum possible stacksize.
                         * It would be better to adjust the
                         * mmap'ed region, but some apps do not check
                         * mmap's return value.
                         */
                        p->p_vmspace->vm_maxsaddr = (char *)USRSTACK -
                            p->p_rlimit[RLIMIT_STACK].rlim_cur;
                }

                /* This gives us our maximum stack size */
                if (linux_args->len > STACK_SIZE - GUARD_SIZE)
                        bsd_args.len = linux_args->len;
                else
                        bsd_args.len  = STACK_SIZE - GUARD_SIZE;

                /* This gives us a new BOS.  If we're using VM_STACK, then
                 * mmap will just map the top SGROWSIZ bytes, and let
                 * the stack grow down to the limit at BOS.  If we're
                 * not using VM_STACK we map the full stack, since we
                 * don't have a way to autogrow it.
                 */
                bsd_args.addr -= bsd_args.len;
        } else {
                bsd_args.addr = (caddr_t)linux_args->addr;
                bsd_args.len  = linux_args->len;
        }

        bsd_args.prot = linux_args->prot | PROT_READ;   /* always required
*/
        if (linux_args->flags & LINUX_MAP_ANON)
                bsd_args.fd = -1;
        else
                bsd_args.fd = linux_args->fd;
        bsd_args.pos = ctob(linux_args->pgoff);
        bsd_args.pad = 0;

        return (mmap(p, &bsd_args));
}

Does anyone see anything blatantly wrong with this?

Ken


To Unsubscribe: send mail to [EMAIL PROTECTED]
with "unsubscribe freebsd-hackers" in the body of the message

Reply via email to