To save more space (equivalent to the size of one erase sector of
MTD device) and to achieve faster read and write speeds, a method
for direct writing was introduced at the FTL layer.
This can be accomplished simply by using the following oflags during
the open operation:
1. O_DIRECT. when this flag is passed in, ftl internally uses
the direct write strategy and no read cache is used in ftl;
otherwise, each write will be executed with the minimum
granularity of flash erase sector size which means a
"sector read back - erase sector - write sector" operation
is performed by using a read cache buffer in heap.
2. O_SYNC. When this flag is passed in, we assume that the
flash has been erased in advance and no erasure operation
will be performed internally within ftl. O_SYNC will take
effect only when both O_DIRECT and O_SYNC are passed in
simultaneously.
3. For uniformity, we remapped the mount flag in mount.h and
unified it with the open flag in fcntl.h. The repetitive
parts of their definitions were reused, and the remaining
part of the mount flag redefine to the unused bit of open
flags.
Signed-off-by: jingfei <jingfei@xiaomi.com>
Most tools used for compliance and SBOM generation use SPDX identifiers
This change brings us a step closer to an easy SBOM generation.
Signed-off-by: Alin Jerpelea <alin.jerpelea@sony.com>
The memory allocated with strdup and asprintf is done via lib_malloc
so we need to use lib_free to deallocate memory otherwise the assertion
"Free memory from the wrong heap" is hit with flat mode and user separated
heap enabled mode.
Signed-off-by: Petro Karashchenko <petro.karashchenko@gmail.com>
on the other hand, open/nx_open call file_open instead
Signed-off-by: Xiang Xiao <xiaoxiang@xiaomi.com>
Change-Id: I66990a77cdeb6ff18f7bf48a65bbc7b701dad552
Resolution of Issue 619 will require multiple steps, this part of the first step in that resolution: Every call to nxsem_wait_uninterruptible() must handle the return value from nxsem_wait_uninterruptible properly. This commit is only for those files under fs/driver, fs/aio, fs/nfs, crypto/, and boards/.
Please note: The modified file under fs/nfs generates several " Mixed case identifier found" errors. Please ignore these. These cannot be fixed without changes to numerous other files. They also follow a non-standard convention that is used many files: Using lower case structure names in custom SIZEOF_ definitions.
* Simplify EINTR/ECANCEL error handling
1. Add semaphore uninterruptible wait function
2 .Replace semaphore wait loop with a single uninterruptible wait
3. Replace all sem_xxx to nxsem_xxx
* Unify the void cast usage
1. Remove void cast for function because many place ignore the returned value witout cast
2. Replace void cast for variable with UNUSED macro
many locations: Change occurences of open() followed by file_detach() to file_open(). Change most non-controversion calls to open() to nx_open().
fs/inode/fs_fileopen.c: Flesh out file_open() with some interim, placeholder logic.
fs/inode/fs_fileopen.c: Add a framework for a file_open() implementation (no real logic in place yet).
fs/vfs/fs_open.c: Add nx_open() which is the same as open() except that it does not create a cancellation point nor does it modify the errno variable.
This commit backs out most of commit b4747286b1. That change was added because sem_wait() would sometimes cause cancellation points inappropriated. But with these recent changes, nxsem_wait() is used instead and it is not a cancellation point.
In the OS, all calls to sem_wait() changed to nxsem_wait(). nxsem_wait() does not return errors via errno so each place where nxsem_wait() is now called must not examine the errno variable.
In all OS functions (not libraries), change sem_wait() to nxsem_wait(). This will prevent the OS from creating bogus cancellation points and from modifying the per-task errno variable.
sched/semaphore: Add the function nxsem_wait(). This is a new internal OS interface. It is functionally equivalent to sem_wait() except that (1) it is not a cancellation point, and (2) it does not set the per-thread errno value on return.
sched/semaphore: Add nxsem_post() which is identical to sem_post() except that it never modifies the errno variable. Changed all references to sem_post in the OS to nxsem_post().
sched/semaphore: Add nxsem_destroy() which is identical to sem_destroy() except that it never modifies the errno variable. Changed all references to sem_destroy() in the OS to nxsem_destroy().
libc/semaphore and sched/semaphore: Add nxsem_getprotocol() and nxsem_setprotocola which are identical to sem_getprotocol() and set_setprotocol() except that they never modifies the errno variable. Changed all references to sem_setprotocol in the OS to nxsem_setprotocol(). sem_getprotocol() was not used in the OS