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-rw-r--r--devio/devpager.c257
1 files changed, 0 insertions, 257 deletions
diff --git a/devio/devpager.c b/devio/devpager.c
deleted file mode 100644
index 1f3b3ee1..00000000
--- a/devio/devpager.c
+++ /dev/null
@@ -1,257 +0,0 @@
-/* A pager interface for raw mach devices.
-
- Copyright (C) 1995 Free Software Foundation, Inc.
-
- Written by Miles Bader <miles@gnu.ai.mit.edu>
-
- This program is free software; you can redistribute it and/or
- modify it under the terms of the GNU General Public License as
- published by the Free Software Foundation; either version 2, or (at
- your option) any later version.
-
- This program is distributed in the hope that it will be useful, but
- WITHOUT ANY WARRANTY; without even the implied warranty of
- MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
- General Public License for more details.
-
- You should have received a copy of the GNU General Public License
- along with this program; if not, write to the Free Software
- Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA. */
-
-#include <hurd.h>
-#include <hurd/pager.h>
-#include <device/device.h>
-#include <assert.h>
-
-#include "dev.h"
-
-/* ---------------------------------------------------------------- */
-/* Pager library callbacks; see <hurd/pager.h> for more info. */
-
-/* For pager PAGER, read one page from offset PAGE. Set *BUF to be the
- address of the page, and set *WRITE_LOCK if the page must be provided
- read-only. The only permissable error returns are EIO, EDQUOT, and
- ENOSPC. */
-error_t
-pager_read_page(struct user_pager_info *upi,
- vm_offset_t page, vm_address_t *buf, int *writelock)
-{
- error_t err;
- int read; /* bytes actually read */
- int want = vm_page_size; /* bytes we want to read */
- struct dev *dev = (struct dev *)upi;
-
- if (page + want > dev->size)
- /* Read a partial page if necessary to avoid reading off the end. */
- want = dev->size - page;
-
- err = device_read(dev->port, 0, page / dev->dev_block_size, want,
- (io_buf_ptr_t *)buf, &read);
-
- if (!err && want < vm_page_size)
- /* Zero anything we didn't read. Allocation only happens in page-size
- multiples, so we know we can write there. */
- bzero((char *)*buf + want, vm_page_size - want);
-
- *writelock = (dev->flags & DEV_READONLY);
-
- if (err || read < want)
- return EIO;
- else
- return 0;
-}
-
-/* For pager PAGER, synchronously write one page from BUF to offset PAGE. In
- addition, vm_deallocate (or equivalent) BUF. The only permissable error
- returns are EIO, EDQUOT, and ENOSPC. */
-error_t
-pager_write_page(struct user_pager_info *upi,
- vm_offset_t page, vm_address_t buf)
-{
- struct dev *dev = (struct dev *)upi;
-
- if (dev->flags & DEV_READONLY)
- return EROFS;
- else
- {
- error_t err;
- int written;
- int want = vm_page_size;
-
- if (page + want > dev->size)
- /* Write a partial page if necessary to avoid reading off the end. */
- want = dev->size - page;
-
- err = device_write(dev->port, 0, page / dev->dev_block_size,
- (io_buf_ptr_t)buf, want, &written);
-
- vm_deallocate(mach_task_self(), buf, vm_page_size);
-
- if (err || written < want)
- return EIO;
- else
- return 0;
- }
-}
-
-/* A page should be made writable. */
-error_t
-pager_unlock_page(struct user_pager_info *upi, vm_offset_t address)
-{
- struct dev *dev = (struct dev *)upi;
-
- if (dev->flags & DEV_READONLY)
- return EROFS;
- else
- return 0;
-}
-
-/* The user must define this function. It should report back (in
- *OFFSET and *SIZE the minimum valid address the pager will accept
- and the size of the object. */
-error_t
-pager_report_extent(struct user_pager_info *upi,
- vm_address_t *offset, vm_size_t *size)
-{
- *offset = 0;
- *size = ((struct dev *)upi)->size;
- return 0;
-}
-
-/* This is called when a pager is being deallocated after all extant send
- rights have been destroyed. */
-void
-pager_clear_user_data(struct user_pager_info *upi)
-{
-}
-
-/* ---------------------------------------------------------------- */
-
-/* A top-level function for the paging thread that just services paging
- requests. */
-static void
-service_paging_requests (any_t arg)
-{
- struct dev *dev = (struct dev *)arg;
- for (;;)
- ports_manage_port_operations_multithread (dev->pager_port_bucket,
- pager_demuxer,
- 1000 * 30, 1000 * 60 * 5,
- 1, MACH_PORT_NULL);
-}
-
-/* Initialize paging for this device. */
-static void
-init_dev_paging (struct dev *dev)
-{
- dev->pager_port_bucket = ports_create_bucket ();
-
- /* Make a thread to service paging requests. */
- cthread_detach (cthread_fork ((cthread_fn_t)service_paging_requests,
- (any_t)dev));
-}
-
-void
-pager_dropweak (struct user_pager_info *upi __attribute__ ((unused)))
-{
-}
-
-/* ---------------------------------------------------------------- */
-
-/* Try to stop all paging activity on DEV, returning true if we were
- successful. If NOSYNC is true, then we won't write back any (kernel)
- cached pages to the device. */
-int
-dev_stop_paging (struct dev *dev, int nosync)
-{
- int success = 1; /* Initially assume success. */
-
- io_state_lock(&dev->io_state);
-
- if (dev->pager != NULL)
- {
- int num_pagers = ports_count_bucket (dev->pager_port_bucket);
- if (num_pagers > 0 && !nosync)
- {
- error_t block_cache (void *arg)
- {
- struct pager *p = arg;
- pager_change_attributes (p, 0, MEMORY_OBJECT_COPY_DELAY, 1);
- return 0;
- }
- error_t enable_cache (void *arg)
- {
- struct pager *p = arg;
- pager_change_attributes (p, 1, MEMORY_OBJECT_COPY_DELAY, 0);
- return 0;
- }
-
- /* Loop through the pagers and turn off caching one by one,
- synchronously. That should cause termination of each pager. */
- ports_bucket_iterate (dev->pager_port_bucket, block_cache);
-
- /* Give it a second; the kernel doesn't actually shutdown
- immediately. XXX */
- sleep (1);
-
- num_pagers = ports_count_bucket (dev->pager_port_bucket);
- if (num_pagers > 0)
- /* Darn, there are actual honest users. Turn caching back on,
- and return failure. */
- {
- ports_bucket_iterate (dev->pager_port_bucket, enable_cache);
- success = 0;
- }
- }
-
- if (success && !nosync)
- /* shutdown the pager on DEV. If NOSYNC is set, we don't bother, for
- fear that this may result in I/O. In this case we've disabled
- rpcs on the pager's ports, so this will result in hanging... What
- do we do??? XXXX */
- pager_shutdown (dev->pager);
- }
-
- if (success)
- dev->pager = NULL;
-
- io_state_lock(&dev->io_state);
-
- return success;
-}
-
-/* ---------------------------------------------------------------- */
-
-/* Returns in MEMOBJ the port for a memory object backed by the storage on
- DEV. Returns 0 or the error code if an error occurred. */
-error_t
-dev_get_memory_object(struct dev *dev, memory_object_t *memobj)
-{
- if (dev_is(dev, DEV_SERIAL))
- return ENODEV;
-
- io_state_lock(&dev->io_state);
- if (dev->pager_port_bucket == NULL)
- init_dev_paging (dev);
- if (dev->pager == NULL)
- dev->pager =
- pager_create((struct user_pager_info *)dev, dev->pager_port_bucket,
- 1, MEMORY_OBJECT_COPY_DELAY);
- else
- ports_port_ref (dev->pager);
- io_state_unlock(&dev->io_state);
-
- if (dev->pager == NULL)
- return ENODEV; /* XXX ??? */
-
- *memobj = pager_get_port(dev->pager);
- ports_port_deref (dev->pager); /* Drop our original ref on PAGER. */
-
- if (*memobj != MACH_PORT_NULL)
- return
- mach_port_insert_right(mach_task_self(),
- *memobj, *memobj,
- MACH_MSG_TYPE_MAKE_SEND);
-
- return 0;
-}
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