wo...@planix.ca ("Greg A. Woods") writes: >Given the layers of devices and code involved, perhaps it might be >possible to just honour the original mode requested by the code opening >the first partition to mount a filesystem, and then to upgrade the vnode >to write mode if/when that mount is upgraded to write mode or another rw >mount is attempted on another partition on the same device?
Someone would need to write code to "upgrade" vnodes. I doubt that's trivial. Fortunately it is not necessary. If the parent device is read-only, no "upgrade" will help to make it read-write. So you open read-write or fail back to read-only when necessary. An attempt to open a wedge read-write on a read-only opened parent device then has to fail. I'm testing a patch for that...