On Jun 23, 2009 20:02 -0400, Greg Freemyer wrote: > On Tue, Jun 23, 2009 at 7:19 PM, Andreas Dilger<adilger@xxxxxxx> wrote: > > On Jun 23, 2009 17:25 +0900, Akira Fujita wrote: > >> alloc_flag of ext4_alloc_rule structure is set as "mandatory" or "advisory". > >> Restricted blocks with "mandatory" are never used by block allocator. > >> But in "advisory" case, block allocator is allowed to use restricted blocks > >> when there are no free blocks on FS. > > > > Would it make more sense to implement the range protections via the > > existing preallocation ranges (PA)? An inode can have multiple > > PAs attached to it to have it prefer allocations from that range. > > > > We could also attach PAs to the superblock to prevent other files from > > allocating out of those ranges. This would work better with the existing > > allocation code instead of creating a second similar mechanism. > > Where can I find documentation about how PA works? Or is it just in > the source? If so, what are one or two calls that cause the PA ranges > to be set, etc. Aneesh is the expert on the preallocation code. Cheers, Andreas -- Andreas Dilger Sr. Staff Engineer, Lustre Group Sun Microsystems of Canada, Inc. -- To unsubscribe from this list: send the line "unsubscribe linux-ext4" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
