Messages in this thread Patch in this message | | | Date | Sat, 7 Dec 2002 20:55:50 +0000 (GMT) | From | Peter Benie <> | Subject | [PATCH] [2.2] pipe_write can block even with non-blocking fd |
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Please apply the following patch. This makes non-blocking writes to pipe actually non-blocking.
A program that demonstrates the bug can be found at: http://www.chiark.greenend.org.uk/~peterb/linux/nonblock/pipe-testnonblock.c
--- 2.2.19/fs/pipe.c.orig Thu Dec 6 21:20:38 2001 +++ 2.2.19/fs/pipe.c Thu Dec 6 21:22:47 2001 @@ -105,9 +105,17 @@ else free = 1; /* can't do it atomically, wait for any free space */ up(&inode->i_sem); - if (down_interruptible(&inode->i_atomic_write)) { - down(&inode->i_sem); - return -ERESTARTSYS; + if (filp->f_flags & O_NONBLOCK) { + if (down_trylock(&inode->i_atomic_write)) { + down(&inode->i_sem); + return -ERESTARTSYS; + } + } + else { + if (down_interruptible(&inode->i_atomic_write)) { + down(&inode->i_sem); + return -ERESTARTSYS; + } } while (count>0) { while ((PIPE_FREE(*inode) < free) || PIPE_LOCK(*inode)) { - To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
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