posix_lock_file
Synopsis
int posix_lock_file (struct file * filp, struct file_lock * caller, unsigned int wait);
Arguments
filp The file to apply the lock to
caller The lock to be applied
wait 1 to retry automatically, 0 to return -EAGAIN
Description
Add a POSIX style lock to a file.
We merge adjacent locks whenever possible. POSIX locks are sorted by owner
task, then by starting address
Kai Petzke writes
To make freeing a lock much faster, we keep a pointer to the lock before the
actual one. But the real gain of the new coding was, that lock_it and
unlock_it became one function.
To all purists
Yes, I use a few goto's. Just pass on to the next function.