diff options
Diffstat (limited to 'storeio/dev.c')
| -rw-r--r-- | storeio/dev.c | 58 |
1 files changed, 25 insertions, 33 deletions
diff --git a/storeio/dev.c b/storeio/dev.c index 0a713253..ba57f23f 100644 --- a/storeio/dev.c +++ b/storeio/dev.c @@ -1,8 +1,7 @@ /* store `device' I/O - Copyright (C) 1995, 1996, 1998, 1999 Free Software Foundation, Inc. - - Written by Miles Bader <miles@gnu.ai.mit.edu> + Copyright (C) 1995,96,98,99,2000 Free Software Foundation, Inc. + Written by Miles Bader <miles@gnu.org> This program is free software; you can redistribute it and/or modify it under the terms of the GNU General Public License as @@ -133,55 +132,49 @@ dev_buf_rw (struct dev *dev, size_t buf_offs, size_t *io_offs, size_t *len, } } -/* Returns a pointer to a new device structure in DEV for the kernel device - NAME, with the given FLAGS. If BLOCK_SIZE is non-zero, it should be the - desired block size, and must be a multiple of the device block size. - If an error occurs, the error code is returned, otherwise 0. */ +/* Called with DEV->lock held. Try to open the store underlying DEV. */ error_t -dev_open (struct store_parsed *name, int flags, int inhibit_cache, - struct dev **dev) +dev_open (struct dev *dev) { error_t err; - struct dev *new = malloc (sizeof (struct dev)); - if (! new) - return ENOMEM; + assert (dev->store == 0); - err = store_parsed_open (name, flags, &new->store); + err = store_parsed_open (dev->store_name, + dev->readonly ? STORE_READONLY : 0, + &dev->store); if (err) - { - free (new); - return err; - } + return err; - new->buf = mmap (0, new->store->block_size, PROT_READ|PROT_WRITE, + dev->buf = mmap (0, dev->store->block_size, PROT_READ|PROT_WRITE, MAP_ANON, 0, 0); - if (new->buf == (void *) -1) + if (dev->buf == MAP_FAILED) { - store_free (new->store); - free (new); + store_free (dev->store); + dev->store = 0; return ENOMEM; } - new->inhibit_cache = inhibit_cache; - new->owner = 0; - if (!inhibit_cache) + if (!dev->inhibit_cache) { - new->buf_offs = -1; - rwlock_init (&new->io_lock); - new->block_mask = (1 << new->store->log2_block_size) - 1; - new->pager = 0; - mutex_init (&new->pager_lock); + dev->buf_offs = -1; + rwlock_init (&dev->io_lock); + dev->block_mask = (1 << dev->store->log2_block_size) - 1; + dev->pager = 0; + mutex_init (&dev->pager_lock); } - *dev = new; return 0; } -/* Free DEV and any resources it consumes. */ +/* Shut down the store underlying DEV and free any resources it consumes. + DEV itself remains intact so that dev_open can be called again. + This should be called with DEV->lock held. */ void dev_close (struct dev *dev) { + assert (dev->store); + if (!dev->inhibit_cache) { if (dev->pager != NULL) @@ -193,8 +186,7 @@ dev_close (struct dev *dev) } store_free (dev->store); - - free (dev); + dev->store = 0; } /* Try and write out any pending writes to DEV. If WAIT is true, will wait |