cpukit/flash: Add API for Flash devices

1 files changed, 902 insertions, 0 deletions

diff --git a/cpukit/dev/flash/flashdev.c b/cpukit/dev/flash/flashdev.c
new file mode 100644
index 0000000000..4b7a0560ff
--- /dev/null
+++ b/cpukit/dev/flash/flashdev.c
@@ -0,0 +1,902 @@
+/*
+ * Copyright (C) 2023 Aaron Nyholm
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ * 1. Redistributions of source code must retain the above copyright
+ *    notice, this list of conditions and the following disclaimer.
+ * 2. Redistributions in binary form must reproduce the above copyright
+ *    notice, this list of conditions and the following disclaimer in the
+ *    documentation and/or other materials provided with the distribution.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
+ * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
+ * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
+ * ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE
+ * LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
+ * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
+ * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
+ * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
+ * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
+ * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
+ * POSSIBILITY OF SUCH DAMAGE.
+ */
+
+#ifdef HAVE_CONFIG_H
+#include "config.h"
+#endif
+
+#include <dev/flash/flashdev.h>
+
+#include <rtems/imfs.h>
+#include <rtems/score/assert.h>
+
+#include <errno.h>
+#include <fcntl.h>
+#include <stdlib.h>
+#include <string.h>
+#include <unistd.h>
+#include <assert.h>
+
+#define RTEMS_FLASHDEV_REGION_ALLOC_FULL 0xFFFFFFFFUL
+#define RTEMS_FLASHDEV_REGION_UNDEFINED 0xFFFFFFFFUL
+#define RTEMS_FLASHDEV_REGION_BITALLOC_LENGTH 32
+
+#define RTEMS_FLASHDEV_BITALLOC_LENGTH(t) \
+  (t->max_regions/RTEMS_FLASHDEV_REGION_BITALLOC_LENGTH)
+#define RTEMS_FLASHDEV_BITALLOC_FINAL_BITS(t) \
+  (t->max_regions%RTEMS_FLASHDEV_REGION_BITALLOC_LENGTH)
+
+static int rtems_flashdev_do_init(
+  rtems_flashdev *flash,
+  void ( *destroy )( rtems_flashdev *flash )
+);
+
+static int rtems_flashdev_read_write(
+  rtems_libio_t *iop,
+  const void *write_buff,
+  void *read_buff,
+  size_t count
+);
+
+static int rtems_flashdev_ioctl_erase(
+  rtems_flashdev *flash,
+  rtems_libio_t *iop,
+  void *arg
+);
+
+static off_t rtems_flashdev_get_region_offset(
+  rtems_flashdev *flash,
+  rtems_libio_t *iop
+);
+
+static size_t rtems_flashdev_get_region_size(
+  rtems_flashdev *flash,
+  rtems_libio_t *iop
+);
+
+static int rtems_flashdev_ioctl_set_region(
+  rtems_flashdev *flash,
+  rtems_libio_t *iop,
+  void *arg
+);
+
+static int rtems_flashdev_ioctl_create_region(
+  rtems_flashdev *flash,
+  rtems_libio_t *iop,
+  rtems_flashdev_region *region_in
+);
+
+static int rtems_flashdev_ioctl_update_region(
+  rtems_flashdev *flash,
+  rtems_libio_t *iop,
+  rtems_flashdev_region *region_in
+);
+
+static int rtems_flashdev_ioctl_clear_region(
+  rtems_flashdev *flash,
+  rtems_libio_t *iop
+);
+
+static uint32_t rtems_flashdev_ioctl_jedec_id(
+  rtems_flashdev *flash
+);
+
+static uint32_t rtems_flashdev_ioctl_flash_type(
+  rtems_flashdev *flash,
+  void *arg
+);
+
+static int rtems_flashdev_ioctl_pageinfo_offset(
+  rtems_flashdev *flash,
+  void *arg
+);
+
+static int rtems_flashdev_ioctl_pageinfo_index(
+  rtems_flashdev *flash,
+  void *arg
+);
+
+static int rtems_flashdev_ioctl_page_count(
+  rtems_flashdev *flash,
+  void *arg
+);
+
+static int rtems_flashdev_ioctl_write_block_size(
+  rtems_flashdev *flash,
+  void *arg
+);
+
+static int rtems_flashdev_get_addr(
+  rtems_flashdev *flash,
+  rtems_libio_t *iop,
+  size_t count,
+  off_t *addr
+);
+
+static int rtems_flashdev_update_and_return(
+  rtems_libio_t *iop,
+  int status,
+  size_t count,
+  off_t new_offset
+);
+
+static uint32_t rtems_flashdev_find_unallocated_region(
+  rtems_flashdev_region_table *region_table
+);
+
+static uint32_t rtems_flashdev_set_region(
+  rtems_flashdev_region_table *region_table,
+  int index
+);
+
+static uint32_t rtems_flashdev_unset_region(
+  rtems_flashdev_region_table *region_table,
+  int index
+);
+
+static uint32_t rtems_flashdev_check_allocation(
+  rtems_flashdev_region_table *region_table,
+  int index
+);
+
+static int rtems_flashdev_open(
+  rtems_libio_t *iop,
+  const char *path,
+  int oflag,
+  mode_t mode
+);
+
+static int rtems_flashdev_close(
+  rtems_libio_t *iop
+);
+
+static ssize_t rtems_flashdev_read(
+  rtems_libio_t *iop,
+  void *buffer,
+  size_t count
+);
+
+static ssize_t rtems_flashdev_write(
+  rtems_libio_t *iop,
+  const void *buffer,
+  size_t count
+);
+
+static int rtems_flashdev_ioctl(
+  rtems_libio_t *iop,
+  ioctl_command_t command,
+  void *arg
+);
+
+static off_t rtems_flashdev_lseek(
+  rtems_libio_t *iop,
+  off_t offset,
+  int whence
+);
+
+static void rtems_flashdev_node_destroy(
+  IMFS_jnode_t *node
+);
+
+static const rtems_filesystem_file_handlers_r rtems_flashdev_handler = {
+  .open_h = rtems_flashdev_open,
+  .close_h = rtems_flashdev_close,
+  .read_h = rtems_flashdev_read,
+  .write_h = rtems_flashdev_write,
+  .ioctl_h = rtems_flashdev_ioctl,
+  .lseek_h = rtems_flashdev_lseek,
+  .fstat_h = IMFS_stat,
+  .ftruncate_h = rtems_filesystem_default_ftruncate,
+  .fsync_h = rtems_filesystem_default_fsync_or_fdatasync,
+  .fdatasync_h = rtems_filesystem_default_fsync_or_fdatasync,
+  .fcntl_h = rtems_filesystem_default_fcntl,
+  .kqfilter_h = rtems_filesystem_default_kqfilter,
+  .mmap_h = rtems_filesystem_default_mmap,
+  .poll_h = rtems_filesystem_default_poll,
+  .readv_h = rtems_filesystem_default_readv,
+  .writev_h = rtems_filesystem_default_writev };
+
+static const IMFS_node_control
+  rtems_flashdev_node_control = IMFS_GENERIC_INITIALIZER(
+    &rtems_flashdev_handler,
+    IMFS_node_initialize_generic,
+    rtems_flashdev_node_destroy
+);
+
+static void rtems_flashdev_node_destroy(
+  IMFS_jnode_t *node
+)
+{
+  rtems_flashdev *flash;
+
+  flash = IMFS_generic_get_context_by_node( node );
+
+  ( *flash->destroy )( flash );
+
+  IMFS_node_destroy_default( node );
+}
+
+static uint32_t rtems_flashdev_get_region_index(
+  rtems_libio_t *iop
+)
+{
+  return (uint32_t)iop->data0;
+}
+
+static int rtems_flashdev_is_region_defined(
+  rtems_libio_t *iop
+)
+{
+  return (rtems_flashdev_get_region_index( iop ) != RTEMS_FLASHDEV_REGION_UNDEFINED);
+}
+
+static void rtems_flashdev_set_region_index(
+  rtems_libio_t *iop,
+  uint32_t index
+)
+{
+  iop->data0 = index;
+}
+
+static int rtems_flashdev_check_offset_region(
+  rtems_flashdev *flash,
+  rtems_libio_t *iop,
+  off_t offset
+)
+{
+  if ( ( rtems_flashdev_is_region_defined( iop ) ) &&
+       ( offset > rtems_flashdev_get_region_size( flash, iop ) ) ) {
+    rtems_set_errno_and_return_minus_one( EINVAL );
+  }
+  return 0;
+}
+
+static void rtems_flashdev_obtain( rtems_flashdev *flash )
+{
+  rtems_recursive_mutex_lock( &flash->mutex );
+}
+
+static void rtems_flashdev_release( rtems_flashdev *flash )
+{
+  rtems_recursive_mutex_unlock( &flash->mutex );
+}
+
+static ssize_t rtems_flashdev_read(
+  rtems_libio_t *iop,
+  void *buffer,
+  size_t count
+)
+{
+  return rtems_flashdev_read_write( iop, NULL, buffer, count );
+}
+
+static ssize_t rtems_flashdev_write(
+  rtems_libio_t *iop,
+  const void *buffer,
+  size_t count
+)
+{
+  return rtems_flashdev_read_write( iop, buffer, NULL, count);
+}
+
+static int rtems_flashdev_read_write(
+  rtems_libio_t *iop,
+  const void *write_buff,
+  void *read_buff,
+  size_t count
+)
+{
+  rtems_flashdev *flash = IMFS_generic_get_context_by_iop( iop );
+  off_t addr;
+  int status;
+
+  if ( read_buff == NULL && write_buff == NULL ) {
+    return 0;
+  }
+
+  /* Get flash address */
+  status = rtems_flashdev_get_addr( flash, iop, count, &addr );
+  if ( status < 0 ) {
+    return status;
+  }
+
+  /* Read or Write to flash */
+  rtems_flashdev_obtain( flash );
+  if ( read_buff != NULL ) {
+    status = ( *flash->read )( flash, addr, count, read_buff );
+  } else if ( write_buff != NULL ) {
+    status = ( *flash->write )( flash, addr, count, write_buff );
+  }
+  rtems_flashdev_release( flash );
+
+  /* Update offset and return */
+  return rtems_flashdev_update_and_return( iop, status, count, addr + count );
+}
+
+static int rtems_flashdev_ioctl(
+  rtems_libio_t *iop,
+  ioctl_command_t command,
+  void *arg
+)
+{
+  rtems_flashdev *flash = IMFS_generic_get_context_by_iop( iop );
+  int err = 0;
+
+  rtems_flashdev_obtain( flash );
+
+  switch ( command ) {
+    case RTEMS_FLASHDEV_IOCTL_OBTAIN:
+      rtems_flashdev_obtain( flash );
+      err = 0;
+      break;
+    case RTEMS_FLASHDEV_IOCTL_RELEASE:
+      rtems_flashdev_release( flash );
+      err = 0;
+      break;
+    case RTEMS_FLASHDEV_IOCTL_JEDEC_ID:
+      *( (uint32_t *) arg ) = rtems_flashdev_ioctl_jedec_id( flash );
+      err = 0;
+      break;
+    case RTEMS_FLASHDEV_IOCTL_ERASE:
+      err = rtems_flashdev_ioctl_erase( flash, iop, arg );
+      break;
+    case RTEMS_FLASHDEV_IOCTL_REGION_SET:
+      err = rtems_flashdev_ioctl_set_region( flash, iop, arg );
+      break;
+    case RTEMS_FLASHDEV_IOCTL_REGION_UNSET:
+      err = rtems_flashdev_ioctl_clear_region( flash, iop );
+      break;
+    case RTEMS_FLASHDEV_IOCTL_TYPE:
+      err = rtems_flashdev_ioctl_flash_type( flash, arg );
+      break;
+    case RTEMS_FLASHDEV_IOCTL_PAGEINFO_BY_OFFSET:
+      err = rtems_flashdev_ioctl_pageinfo_offset( flash, arg );
+      break;
+    case RTEMS_FLASHDEV_IOCTL_PAGEINFO_BY_INDEX:
+      err = rtems_flashdev_ioctl_pageinfo_index( flash, arg );
+      break;
+    case RTEMS_FLASHDEV_IOCTL_PAGE_COUNT:
+      err = rtems_flashdev_ioctl_page_count( flash, arg );
+      break;
+    case RTEMS_FLASHDEV_IOCTL_WRITE_BLOCK_SIZE:
+      err = rtems_flashdev_ioctl_write_block_size( flash, arg );
+      break;
+  }
+
+  rtems_flashdev_release( flash );
+  if ( err != 0 ) {
+    rtems_set_errno_and_return_minus_one( err );
+  } else {
+    return 0;
+  }
+}
+
+static off_t rtems_flashdev_lseek(
+  rtems_libio_t *iop,
+  off_t offset,
+  int whence
+)
+{
+  off_t tmp_offset;
+  rtems_flashdev *flash = IMFS_generic_get_context_by_iop( iop );
+
+  if ( offset < 0 ) {
+    rtems_set_errno_and_return_minus_one( EINVAL );
+  }
+
+  switch ( whence ) {
+    case SEEK_CUR:
+      tmp_offset = iop->offset + offset;
+      break;
+    case SEEK_SET:
+      tmp_offset = offset;
+      break;
+    case SEEK_END:
+    default:
+      rtems_set_errno_and_return_minus_one( EINVAL );
+  }
+
+  if ( ( rtems_flashdev_is_region_defined(iop) ) &&
+       ( tmp_offset > rtems_flashdev_get_region_size( flash, iop ) ) ) {
+    rtems_set_errno_and_return_minus_one( EINVAL );
+  }
+
+  iop->offset = tmp_offset;
+  return iop->offset;
+}
+
+static int rtems_flashdev_close(
+  rtems_libio_t *iop
+)
+{
+  rtems_flashdev *flash = IMFS_generic_get_context_by_iop( iop );
+  rtems_flashdev_ioctl_clear_region( flash, iop );
+  return rtems_filesystem_default_close( iop );
+}
+
+static int rtems_flashdev_open(
+  rtems_libio_t *iop,
+  const char *path,
+  int oflag,
+  mode_t mode
+)
+{
+  int ret = rtems_filesystem_default_open( iop, path, oflag, mode );
+  rtems_flashdev_set_region_index(iop, RTEMS_FLASHDEV_REGION_UNDEFINED);
+  return ret;
+}
+
+int rtems_flashdev_register(
+  rtems_flashdev *flash,
+  const char *flash_path
+)
+{
+  int rv;
+  rtems_flashdev_region_table *table = flash->region_table;
+  int alloc_array_len;
+
+  rv = IMFS_make_generic_node(
+    flash_path,
+    S_IFCHR | S_IRWXU | S_IRWXG | S_IRWXO,
+    &rtems_flashdev_node_control,
+    flash
+  );
+
+  if ( rv != 0 ) {
+    ( *flash->destroy )( flash );
+  }
+
+  alloc_array_len = RTEMS_FLASHDEV_BITALLOC_LENGTH(table) +
+    ((RTEMS_FLASHDEV_BITALLOC_FINAL_BITS(table)) != 0);
+
+  memset(table->bit_allocator, 0, alloc_array_len);
+
+  return rv;
+}
+
+static int rtems_flashdev_do_init(
+  rtems_flashdev *flash,
+  void ( *destroy )( rtems_flashdev *flash )
+)
+{
+  rtems_recursive_mutex_init( &flash->mutex, "RTEMS_FLASHDEV Flash" );
+  flash->destroy = destroy;
+  flash->read = NULL;
+  flash->write = NULL;
+  flash->erase = NULL;
+  flash->jedec_id = NULL;
+  flash->flash_type = NULL;
+  flash->page_info_by_offset = NULL;
+  flash->page_info_by_index = NULL;
+  flash->page_count = NULL;
+  flash->write_block_size = NULL;
+  flash->region_table = NULL;
+  return 0;
+}
+
+void rtems_flashdev_destroy( rtems_flashdev *flash )
+{
+  rtems_recursive_mutex_destroy( &flash->mutex );
+}
+
+void rtems_flashdev_destroy_and_free( rtems_flashdev *flash )
+{
+  if ( flash == NULL ) {
+    return;
+  }
+  rtems_recursive_mutex_destroy( &( flash->mutex ) );
+  free( flash );
+  flash = NULL;
+  return;
+}
+
+int rtems_flashdev_init( rtems_flashdev *flash )
+{
+  memset( flash, 0, sizeof( *flash ) );
+
+  return rtems_flashdev_do_init( flash, rtems_flashdev_destroy );
+}
+
+rtems_flashdev *rtems_flashdev_alloc_and_init( size_t size )
+{
+  rtems_flashdev *flash = NULL;
+
+  if ( size >= sizeof( *flash ) ) {
+    flash = calloc( 1, size );
+    if ( flash != NULL ) {
+      int rv;
+
+      rv = rtems_flashdev_do_init( flash, rtems_flashdev_destroy_and_free );
+      if ( rv != 0 ) {
+        rtems_recursive_mutex_destroy( &flash->mutex );
+        free( flash );
+        return NULL;
+      }
+    }
+  }
+
+  return flash;
+}
+
+static int rtems_flashdev_get_addr(
+  rtems_flashdev *flash,
+  rtems_libio_t *iop,
+  size_t count,
+  off_t *addr
+)
+{
+  off_t new_offset;
+
+  /* Check address is in valid region */
+  new_offset = iop->offset + count;
+
+  if (rtems_flashdev_check_offset_region(flash, iop, new_offset)) {
+    return -1;
+  }
+
+  /* Get address for operation */
+  if ( !rtems_flashdev_is_region_defined( iop ) ) {
+    *addr = iop->offset;
+  } else {
+    *addr = ( iop->offset + rtems_flashdev_get_region_offset( flash, iop ) );
+  }
+  return 0;
+}
+
+static int rtems_flashdev_update_and_return(
+  rtems_libio_t *iop,
+  int status,
+  size_t count,
+  off_t new_offset
+)
+{
+  /* Update offset and return */
+  if ( status == 0 ) {
+    iop->offset = new_offset;
+    return count;
+  } else {
+    rtems_set_errno_and_return_minus_one( status );
+  }
+}
+
+static int rtems_flashdev_ioctl_erase(
+  rtems_flashdev *flash,
+  rtems_libio_t *iop,
+  void *arg
+)
+{
+  rtems_flashdev_region *erase_args_1;
+  off_t check_offset;
+  int status;
+
+  if ( flash->erase == NULL ) {
+    return 0;
+  }
+
+  erase_args_1 = (rtems_flashdev_region *) arg;
+  /* Check erasing valid region */
+  check_offset = erase_args_1->offset + erase_args_1->size;
+  if ( rtems_flashdev_is_region_defined( iop ) && (
+         rtems_flashdev_check_offset_region(flash, iop, check_offset) ||
+         ( erase_args_1->offset <
+           rtems_flashdev_get_region_offset( flash, iop ) ) ) ) {
+    rtems_set_errno_and_return_minus_one( EINVAL );
+  }
+
+  /* Erase flash */
+  status = ( *flash->erase )( flash, erase_args_1->offset, erase_args_1->size );
+  return status;
+}
+
+static int rtems_flashdev_ioctl_set_region(
+  rtems_flashdev *flash,
+  rtems_libio_t *iop,
+  void *arg
+)
+{
+  rtems_flashdev_region *region_in;
+  rtems_flashdev_region_table *table = flash->region_table;
+  region_in = (rtems_flashdev_region *) arg;
+
+  if (flash->region_table == NULL) {
+    rtems_set_errno_and_return_minus_one( ENOMEM );
+  }
+
+  if ( !rtems_flashdev_is_region_defined( iop ) ) {
+    if (
+      rtems_flashdev_find_unallocated_region(table)
+        == RTEMS_FLASHDEV_REGION_ALLOC_FULL
+    )
+    {
+      /* New region to allocate and all regions allocated */
+      rtems_set_errno_and_return_minus_one( ENOMEM );
+    } else {
+      /* New region to allocate and space to allocate region */
+      return rtems_flashdev_ioctl_create_region( flash, iop, region_in );
+    }
+  } else {
+    /* Updating existing region */
+    return rtems_flashdev_ioctl_update_region( flash, iop, region_in );
+  }
+
+}
+
+static int rtems_flashdev_ioctl_create_region(
+  rtems_flashdev *flash,
+  rtems_libio_t *iop,
+  rtems_flashdev_region *region_in
+)
+{
+  int i;
+  rtems_flashdev_region_table *table = flash->region_table;
+
+  /* Find unallocated region slot */
+  i = rtems_flashdev_find_unallocated_region(flash->region_table);
+  if (i == RTEMS_FLASHDEV_REGION_ALLOC_FULL) {
+    rtems_set_errno_and_return_minus_one( ENOMEM );
+  }
+
+  /* Set region values */
+  table->regions[ i ].offset = region_in->offset;
+  table->regions[ i ].size = region_in->size;
+
+  /* Set region as allocated and link iop */
+  rtems_flashdev_set_region(flash->region_table, i);
+  rtems_flashdev_set_region_index( iop, i );
+
+  return 0;
+}
+
+static int rtems_flashdev_ioctl_update_region(
+  rtems_flashdev *flash,
+  rtems_libio_t *iop,
+  rtems_flashdev_region *region_in
+)
+{
+  uint32_t region_index = rtems_flashdev_get_region_index( iop );
+  rtems_flashdev_region_table *table = flash->region_table;
+
+  /**
+   * If region index is larger then maximum region index or region
+   * index at given index is undefined return an error.
+   */
+  if (
+       ( region_index >= flash->region_table->max_regions ) ||
+       ( rtems_flashdev_check_allocation( table, region_index ) == 0)
+     )
+  {
+    rtems_set_errno_and_return_minus_one( EINVAL );
+  }
+
+  /* Set region values */
+  table->regions[ region_index ].offset = region_in->offset;
+  table->regions[ region_index ].size = region_in->size;
+
+  return 0;
+}
+
+static int rtems_flashdev_ioctl_clear_region(
+  rtems_flashdev *flash,
+  rtems_libio_t *iop
+)
+{
+  uint32_t region_index = rtems_flashdev_get_region_index( iop );
+
+  if (flash->region_table == NULL) {
+    rtems_set_errno_and_return_minus_one( ENOMEM );
+  }
+
+  /* Check region to clear */
+  if ( region_index == RTEMS_FLASHDEV_REGION_UNDEFINED ) {
+    rtems_set_errno_and_return_minus_one( EINVAL );
+  }
+
+  /* Clear region */
+  rtems_flashdev_unset_region( flash->region_table, region_index );
+  rtems_flashdev_set_region_index( iop, RTEMS_FLASHDEV_REGION_UNDEFINED );
+  return 0;
+}
+
+static off_t rtems_flashdev_get_region_offset(
+  rtems_flashdev *flash,
+  rtems_libio_t *iop
+)
+{
+  /* Region is already checked to be defined */
+  assert( rtems_flashdev_get_region_index( iop ) != RTEMS_FLASHDEV_REGION_UNDEFINED );
+  rtems_flashdev_region_table *table = flash->region_table;
+  return table->regions[ rtems_flashdev_get_region_index( iop ) ].offset;
+}
+
+static size_t rtems_flashdev_get_region_size(
+  rtems_flashdev *flash,
+  rtems_libio_t *iop
+)
+{
+  /* Region is already checked to be defined */
+  assert( rtems_flashdev_get_region_index( iop ) != RTEMS_FLASHDEV_REGION_UNDEFINED );
+  rtems_flashdev_region_table *table = flash->region_table;
+  return table->regions[ rtems_flashdev_get_region_index( iop ) ].size;
+}
+
+static uint32_t rtems_flashdev_ioctl_jedec_id( rtems_flashdev *flash )
+{
+  if ( flash->jedec_id == NULL ) {
+    return 0;
+  } else {
+    return ( *flash->jedec_id )( flash );
+  }
+}
+
+static uint32_t rtems_flashdev_ioctl_flash_type(
+  rtems_flashdev *flash,
+  void *arg
+)
+{
+  rtems_flashdev_flash_type *type = (rtems_flashdev_flash_type*)arg;
+  if ( flash->flash_type == NULL ) {
+    return 0;
+  } else {
+    return ( *flash->flash_type )( flash, type );
+  }
+}
+
+static int rtems_flashdev_ioctl_pageinfo_offset(
+  rtems_flashdev *flash,
+  void *arg
+)
+{
+  rtems_flashdev_ioctl_page_info *page_info;
+
+  if ( arg == NULL ) {
+    rtems_set_errno_and_return_minus_one( EINVAL );
+  }
+  if ( flash->page_info_by_offset == NULL ) {
+    return 0;
+  } else {
+    page_info = (rtems_flashdev_ioctl_page_info *) arg;
+    return ( *flash->page_info_by_offset )( flash,
+                                         page_info->location,
+                                         &page_info->page_info.offset,
+                                         &page_info->page_info.size );
+  }
+}
+
+static int rtems_flashdev_ioctl_pageinfo_index( rtems_flashdev *flash,
+                                                void *arg )
+{
+  rtems_flashdev_ioctl_page_info *page_info;
+
+  if ( arg == NULL ) {
+    rtems_set_errno_and_return_minus_one( EINVAL );
+  }
+  if ( flash->page_info_by_index == NULL ) {
+    return 0;
+  } else {
+    page_info = (rtems_flashdev_ioctl_page_info *) arg;
+    return ( *flash->page_info_by_index )( flash,
+                                           page_info->location,
+                                           &page_info->page_info.offset,
+                                           &page_info->page_info.size );
+  }
+}
+
+static int rtems_flashdev_ioctl_page_count( rtems_flashdev *flash, void *arg )
+{
+  if ( arg == NULL ) {
+    rtems_set_errno_and_return_minus_one( EINVAL );
+  }
+  if ( flash->page_count == NULL ) {
+    return 0;
+  } else {
+    return ( *flash->page_count )( flash, ( (int *) arg ) );
+  }
+}
+
+static int rtems_flashdev_ioctl_write_block_size(
+  rtems_flashdev *flash,
+  void *arg
+)
+{
+  if ( arg == NULL ) {
+    rtems_set_errno_and_return_minus_one( EINVAL );
+  }
+  if ( flash->write_block_size == NULL ) {
+    return 0;
+  } else {
+    return ( *flash->write_block_size )( flash, ( (size_t *) arg ) );
+  }
+}
+
+static uint32_t rtems_flashdev_find_unallocated_region(
+  rtems_flashdev_region_table *region_table
+)
+{
+  int array_index = 0;
+  int bit_index = 0;
+  int shift;
+
+  while ( bit_index < region_table->max_regions) {
+    /* Get uint32_t holding the ith bit */
+    array_index = bit_index / RTEMS_FLASHDEV_REGION_BITALLOC_LENGTH;
+    shift = bit_index % RTEMS_FLASHDEV_REGION_BITALLOC_LENGTH;
+
+    /* Check if region available in next BITALLOC_LENGTH regions */
+    if (
+        (shift == 0) &&
+        (region_table->bit_allocator[ array_index ] == RTEMS_FLASHDEV_REGION_ALLOC_FULL)
+    )
+    {
+      bit_index = bit_index + RTEMS_FLASHDEV_REGION_BITALLOC_LENGTH;
+      continue;
+    }
+
+    /* Check individual bit */
+    if ( ! ( ( ( region_table->bit_allocator[ array_index ] ) >> shift ) & 1UL ) ) {
+      return bit_index;
+    }
+
+    bit_index++;
+  }
+
+  return RTEMS_FLASHDEV_REGION_ALLOC_FULL;
+}
+
+static uint32_t rtems_flashdev_set_region(
+  rtems_flashdev_region_table *region_table,
+  int index
+)
+{
+  int array_index = index / RTEMS_FLASHDEV_REGION_BITALLOC_LENGTH;
+  int shift = index % RTEMS_FLASHDEV_REGION_BITALLOC_LENGTH;
+
+  region_table->bit_allocator[ array_index ] |= 1UL << shift;
+
+  return index;
+}
+
+static uint32_t rtems_flashdev_unset_region(
+  rtems_flashdev_region_table *region_table,
+  int index
+)
+{
+  int array_index = index / RTEMS_FLASHDEV_REGION_BITALLOC_LENGTH;
+  int shift = index % RTEMS_FLASHDEV_REGION_BITALLOC_LENGTH;
+
+  region_table->bit_allocator[ array_index ] &= ~( 1UL << shift );
+
+  return index;
+}
+
+static uint32_t rtems_flashdev_check_allocation(
+  rtems_flashdev_region_table *region_table,
+  int index
+)
+{
+  int array_index = index / RTEMS_FLASHDEV_REGION_BITALLOC_LENGTH;
+  int shift = index%RTEMS_FLASHDEV_REGION_BITALLOC_LENGTH;
+
+  return ( ( region_table->bit_allocator[ array_index ] >> shift ) & 1UL );
+}