RTEMS Filesystem Design Guide
IMFS_initialize()
rtems_filesystem_mount_table_entry_t *mt_entry
imfs_init.c
This function is provided with a filesystem to take care of the internal filesystem management details associated with mounting that filesystem under the RTEMS environment.
It is not responsible for the mounting details associated the filesystem containing the mount point.
The rtems_filesystem_mount_table_entry_t structure contains the key elements below:
rtems_filesystem_location_info_t *mt_point_node,
This structure contains information about the mount point. This allows us to find the ops-table and the handling functions associated with the filesystem containing the mount point.
rtems_filesystem_location_info_t *fs_root_node,
This structure contains information about the root node in the file system to be mounted. It allows us to find the ops-table and the handling functions associated with the filesystem to be mounted.
rtems_filesystem_options_t options,
Read only or read/write access
void *fs_info,
This points to an allocated block of memory the will be used to hold any filesystem specific information of a global nature. This allocated region if important because it allows us to mount the same filesystem type more than once under the RTEMS system. Each instance of the mounted filesystem has its own set of global management information that is separate from the global management information associated with the other instances of the mounted filesystem type.
rtems_filesystem_limits_and_options_t pathconf_info,
The table contains the following set of values associated with the mounted filesystem:
These values are accessed with the pathconf() and the fpathconf () functions.
const char *dev
The is intended to contain a string that identifies the device that contains the filesystem information. The filesystems that are currently implemented are memory based and don't require a device specification.
If the mt_point_node.node_access is NULL then we are mounting the base file system.
The routine will create a directory node for the root of the IMFS file system.
The node will have read, write and execute permissions for owner, group and others.
The node's name will be a null string.
A filesystem information structure(fs_info) will be allocated and initialized for the IMFS filesystem. The fs_info pointer in the mount table entry will be set to point the filesystem information structure.
The pathconf_info element of the mount table will be set to the appropriate table of path configuration constants ( IMFS_LIMITS_AND_OPTIONS ).
The fs_root_node structure will be filled in with the following:
A 0 will be returned to the calling routine if the process succeeded, otherwise a 1 will be returned.
RTEMS Filesystem Design Guide
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