On Mon, Nov 6, 2017 at 11:06 PM, Amir Goldstein <amir73il@xxxxxxxxx> wrote: > On Mon, Nov 6, 2017 at 10:43 PM, Vivek Goyal <vgoyal@xxxxxxxxxx> wrote: >> On Thu, Nov 02, 2017 at 10:38:08PM +0200, Amir Goldstein wrote: >>> For the case of all layers not on the same fs, return the copy up origin >>> inode st_dev/st_ino for non-dir from stat(2). >>> >>> This guaranties constant st_dev/st_ino for non-dir across copy up. >>> Like the same fs case, st_ino of non-dir is also persistent. >>> >>> If the st_dev/st_ino for copied up object would have been the same as >>> that of the real underlying lower file, running diff on underlying lower >>> file and overlay copied up file would result in diff reporting that the >>> two files are equal when in fact, they may have different content. >>> >>> Therefore, unlike the same fs case, st_dev is not persistent because it >>> uses the unique anonymous bdev allocated for the lower layer. >> >> I have a stupid question. I thought st_dev is allocated dynamically and >> is not persistent across reboot. Is that not the case? If yes, then >> it is not persistent for same fs case as well. If yes, above does not >> make sense. >> > > True. That's a garbage text. Will delete it for v8. Replaced with: Therefore, unlike the same fs case, st_dev is not uniform across all overlay object, which is less friednly to du -x. Amir. -- To unsubscribe from this list: send the line "unsubscribe linux-unionfs" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
