Re: [PATCH 1/9] exofs: osd Swiss army knife

Pavel Machek
2009-01-04T20:01:37Z

On Sun 2009-01-04 10:43:09, Boaz Harrosh wrote:
> Pavel Machek wrote:
> > Hi!
> >
> >>> In this patch are all the osd infrastructure that will be used later
> >>> by the file system.
> >>>
> >>> Also the declarations of constants, on disk structures, and prototypes.
> >>>
> >>> And the Kbuild+Kconfig files needed to build the exofs module.
> >>>
> >>>
> >>> ...
> >>>
> >>> +struct exofs_sb_info {
> >>> + struct osd_dev *s_dev; /* returned by get_osd_dev */
> >>> + uint64_t s_pid; /* partition ID of file system*/
> >>> + int s_timeout; /* timeout for OSD operations */
> >>> + uint32_t s_nextid; /* highest object ID used */
> >>> + uint32_t s_numfiles; /* number of files on fs */
> >>> + spinlock_t s_next_gen_lock; /* spinlock for gen # update */
> >>> + u32 s_next_generation; /* next gen # to use */
> >>> + atomic_t s_curr_pending; /* number of pending commands */
> >>> + uint8_t s_cred[OSD_CAP_LEN]; /* all-powerful credential */
> >>> +};
> >>> +
> >>> +/*
> >>> + * our inode flags
> >>> + */
> >>> +#ifdef ARCH_HAS_ATOMIC_UNSIGNED
> >> This doesn't exist, and it would be fairly bad to introduce it. Please
> >> kill the ifdefs.
> >>
> >>> +typedef unsigned exofs_iflags_t;
> >>> +#else
> >>> +typedef unsigned long exofs_iflags_t;
> >>> +#endif
> >> Then please kill the typedef altogether and replace it with `unsigned
> >> long' everywhere
> >
> > Hmmm.. .and at a note somewhere that we assume unsigned long to be atomic...?
> >
>
> I think I'll just use unsigned. It's more then enough I'm not using more then 3
> bits for now. Is unsigned workable for all ARCHs?

Please just use atomic_t.

(see "atomics: document that linux expects certain atomic behaviour"
thread for discussion)
Pavel
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