Reject the removal of file system instance root nodes in rmdir() and
unlink() and return the EBUSY error status. File system instances can
be removed with unmount(). Remove root node special cases in IMFS,
DOSFS, and RFS.
The XDR library has a problem on architectures with short enums like the
default ARM EABI. Short enums means that the size of the enum type is
variable and the smallest integer type to hold all enum values will be
selected. For many enums this is char. The XDR library uses int32_t
for enum_t. There are several evil casts from an enum type to enum_t
which leads to invalid memory accesses on short enum architectures. A
workaround is to add appropriate dummy enum values.
The file size was wrong in the no space left on device condition. This
resulted in turn in a read of an invalid block which lead to an EIO
error status.
The pathconf_limits_and_options field of
rtems_filesystem_mount_table_entry_t is now a const pointer to reduce
the read-write memory demands of file system instances.
The scope of the file system operations is the file system instance.
The scope of the file system node handlers is the file location. The
benefit of moving the operations to the mount table entry is a size
reduction of the file location (rtems_filesystem_location_info_t). The
code size is slightly increased due to additional load instructions.
Restructure rtems_filesystem_mount_table_entry_t to improve cache
efficiency.
It is now the responsibility of the read() and write() handler to update
the offset field of the IO descriptor (rtems_libio_t). This change
makes it possible to protect the IO descriptor from concurrent access by
per file locks.
Script does what is expected and tries to do it as
smartly as possible.
+ remove occurrences of two blank comment lines
next to each other after Id string line removed.
+ remove entire comment blocks which only exited to
contain CVS Ids
+ If the processing left a blank line at the top of
a file, it was removed.
The fat_file_datasync() read every cluster of the file into the cache
and then synchronized it step-by-step. For unmodified buffers this is a
non-operation. For modified buffers this will wake-up the swapout task
which performs then a single buffer write operation. This is usually
quite inefficient. Firstly we do single buffer writes, secondly we
may perform a lot of unnecessary read operations (for huge files this is
really bad), and thirdly this leads likely to cache evictions.
The synchronization procedure is replaced by a simple
rtems_bdbuf_sync_dev(). This has the side-effect that also buffers not
related to the file are synchronized, but since the modified list is
normally short this should be acceptable.
According to POSIX the lseek() function shall not, by itself, extend the
size of a file.
Remove the size field of rtems_libio_t. A file has only one size but
may have multiple open file descriptors. Thus a file size field in the
file descriptor may lead to inconsistencies.
New default handlers rtems_filesystem_default_lseek_file() and
rtems_filesystem_default_lseek_directory().
In case rtems_bdbuf_read() returns an error status, the block device
buffer pointer will be set to NULL. In RFS the chain node of the block
device buffer will be used for RFS purposes. We must not do this after
an erroneous read.
The functions
o rtems_bdbuf_get(),
o rtems_bdbuf_read(),
o rtems_bdbuf_syncdev(), and
o rtems_bdbuf_purge_dev(),
use now the disk device instead of the device identifier. This makes
bdbuf independent of rtems_disk_obtain() and rtems_disk_release(). It
is the responsiblity of the file system to obtain the disk device. This
also reduces the overhead to get a buffer.
The key for the AVL tree uses now the disk device instead of the device
identifier. The pointer is interpreted as an unsigned integer. This
reduces the memory overhead and makes the comparison operation a bit
faster.
Removed function rtems_bdbuf_purge_major(). This function was too
destructive and could have unpredictable side effects.
Generic nodes are an alternative to standard drivers in RTEMS. The
handlers of a generic node are called with less overhead compared to the
standard driver operations. The usage of file system node handlers
enable more features like support for fsync() and fdatasync(). The
generic nodes use the reference counting of the IMFS. This provides
automatic node destruction when the last reference vanishes.
Extend type IMFS_types_union by new type IMFS_generic_t.
Extend enum IMFS_jnode_types_t by IMFS_GENERIC.
Add functions
o IMFS_make_generic_node(),
o IMFS_is_imfs_instance(),
o IMFS_generic_get_context_by_node(),
o IMFS_generic_get_context_by_location(), and
o IMFS_generic_get_context_by_iop().
New test fstests/fsimfsgeneric01.
Add and use structure IMFS_node_control with support functions. This
helps to make high level functions independent of the node type and
reduces the number of branches in the code.
o Removed RTEMS_LIBIO_PERMS_SEARCH.
o Renamed RTEMS_LIBIO_PERMS_READ in RTEMS_FS_PERMS_READ.
o Renamed RTEMS_LIBIO_PERMS_WRITE in RTEMS_FS_PERMS_WRITE.
o Renamed RTEMS_LIBIO_PERMS_EXEC in RTEMS_FS_PERMS_EXEC.
o Renamed RTEMS_LIBIO_FOLLOW_HARD_LINK in RTEMS_FS_FOLLOW_HARD_LINK.
o Renamed RTEMS_LIBIO_FOLLOW_SYM_LINK in RTEMS_FS_FOLLOW_SYM_LINK.
o Renamed RTEMS_LIBIO_MAKE in RTEMS_FS_MAKE.
o Renamed RTEMS_LIBIO_EXCLUSIVE in RTEMS_FS_EXCLUSIVE.
o Renamed RTEMS_LIBIO_ACCEPT_RESIDUAL_DELIMITERS in
RTEMS_FS_ACCEPT_RESIDUAL_DELIMITERS.
o Renamed RTEMS_LIBIO_REJECT_TERMINAL_DOT in
RTEMS_FS_REJECT_TERMINAL_DOT.