posix_lock_file — Apply a POSIX-style lock to a file
int posix_lock_file ( | struct file * filp, |
| struct file_lock * fl, | |
struct file_lock * conflock); |
struct file * filpThe file to apply the lock to
struct file_lock * flThe lock to be applied
struct file_lock * conflockPlace to return a copy of the conflicting lock, if found.
Add a POSIX style lock to a file. We merge adjacent & overlapping locks whenever possible. POSIX locks are sorted by owner task, then by starting address
Note that if called with an FL_EXISTS argument, the caller may determine whether or not a lock was successfully freed by testing the return value for -ENOENT.