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-rw-r--r--ext2fs/storeinfo.c146
1 files changed, 146 insertions, 0 deletions
diff --git a/ext2fs/storeinfo.c b/ext2fs/storeinfo.c
new file mode 100644
index 00000000..bd7e539a
--- /dev/null
+++ b/ext2fs/storeinfo.c
@@ -0,0 +1,146 @@
+/* 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;
+}