081e36e760
Or it could be explained as lockless (for vnode lock) reads. Reads are performed from the node tn_obj object. Tmpfs regular vnode object lifecycle is significantly different from the normal OBJT_VNODE: it is alive as far as ref_count > 0. Ensure liveness of the tmpfs VREG node and consequently v_object inside VOP_READ_PGCACHE by referencing tmpfs node in tmpfs_open(). Provide custom tmpfs fo_close() method on file, to ensure that close is paired with open. Add tmpfs VOP_READ_PGCACHE that takes advantage of all tmpfs quirks. It is quite cheap in code size sense to support page-ins for read for tmpfs even if we do not own tmpfs vnode lock. Also, we can handle holes in tmpfs node without additional efforts, and do not have limitation of the transfer size. Reviewed by: markj Discussed with and benchmarked by: mjg (previous version) Tested by: pho Sponsored by: The FreeBSD Foundation Differential revision: https://reviews.freebsd.org/D26346 |
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| .. | ||
| tmpfs_fifoops.c | ||
| tmpfs_fifoops.h | ||
| tmpfs_subr.c | ||
| tmpfs_vfsops.c | ||
| tmpfs_vnops.c | ||
| tmpfs_vnops.h | ||
| tmpfs.h | ||