Re: how do I mount a read-only filesystem from the "root device" prompt?

[mlelstv%serpens.de@localhost (Michael van Elst)]

woods%planix.ca@localhost ("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...