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/* Access to file layout information
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 <netinet/in.h>
#include "ext2fs.h"
error_t
diskfs_S_file_get_storage_info (struct protid *cred, int *class,
off_t **runs, unsigned *runs_len,
size_t *block_size,
char *dev_name, mach_port_t *dev_port,
mach_msg_type_name_t *dev_port_type,
char **misc, unsigned *misc_len,
int *flags)
{
error_t err = 0;
block_t index = 0;
unsigned num_fs_blocks;
unsigned runs_alloced = 0;
off_t *run = 0;
struct node *node = cred->po->np;
*misc_len = sizeof (long) * 4;
err = vm_allocate (mach_task_self (), (vm_address_t *)misc, *misc_len, 1);
if (err)
return err;
mutex_lock (&node->lock);
num_fs_blocks = node->dn_stat.st_blocks >> log2_stat_blocks_per_fs_block;
while (num_fs_blocks > 0)
{
block_t block;
err = ext2_getblk (node, index++, 0, &block);
if (err == EINVAL)
/* Either a hole, or past the end of the file. */
{
block = 0;
err = 0;
}
if (err)
goto fail;
block <<= log2_dev_blocks_per_fs_block;
if (!run
|| ((block && run[0] >= 0) /* Neither is a hole and... */
? (block != run[0] + run[1]) /* ... BLOCK doesn't follow RUN */
: (block || run[0] >= 0))) /* or ... one is, but not both */
/* Add a new run. */
{
if (run)
/* There are already some runs. */
{
run += 2;
if (run >= *runs + runs_alloced)
/* Add a new page to the end of the existing RUNS array. */
{
err = vm_allocate (mach_task_self (),
(vm_address_t *)&run, vm_page_size, 0);
if (err)
goto fail;
runs_alloced += vm_page_size / sizeof (off_t);
}
}
else
/* Allocate the RUNS array for the first time. */
{
err = vm_allocate (mach_task_self (),
(vm_address_t *)runs, vm_page_size, 1);
if (err)
goto fail;
runs_alloced = vm_page_size / sizeof (off_t);
run = *runs;
}
run[0] = block ?: -1; /* -1 means a hole in RUNS */
run[1] = 0; /* will get extended just below */
}
/* Increase the size of the current run by one filesystem block. */
run[1] += 1 << log2_dev_blocks_per_fs_block;
num_fs_blocks--;
}
if (run)
{
if (run[0] >= 0)
/* Include the current run, as long as it's not a hole. */
runs += 2;
else if (((vm_address_t)run % vm_page_size) == 0)
/* We allocated just *one* too many pages -- the last run is a hole. */
vm_deallocate (mach_task_self (), (vm_address_t)run, vm_page_size);
*runs_len = run - *runs;
}
else
*runs_len = 0;
((long *)*misc)[0] = htonl (node->dn->number);
((long *)*misc)[1] = htonl (dino (node->dn->number)->i_translator);
*class = STORAGE_DEVICE;
*flags = 0;
*block_size = diskfs_device_block_size;
strcpy (dev_name, diskfs_device_name);
if (diskfs_isuid (0, cred))
*dev_port = diskfs_device;
else
*dev_port = MACH_PORT_NULL;
*dev_port_type = MACH_MSG_TYPE_COPY_SEND;
fail:
mutex_unlock (&node->lock);
if (err)
{
if (*runs_len > 0)
vm_deallocate (mach_task_self (), (vm_address_t)*runs,
runs_alloced * sizeof (off_t));
vm_deallocate (mach_task_self (), (vm_address_t)*misc, *misc_len);
}
return err;
}
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