From d866d875f68fdeae63df334d291fe138dc636d96 Mon Sep 17 00:00:00 2001 From: Boaz Harrosh Date: Wed, 28 Sep 2011 14:43:09 +0300 Subject: ore/exofs: Change the type of the devices array (API change) In the pNFS obj-LD the device table at the layout level needs to point to a device_cache node, where it is possible and likely that many layouts will point to the same device-nodes. In Exofs we have a more orderly structure where we have a single array of devices that repeats twice for a round-robin view of the device table This patch moves to a model that can be used by the pNFS obj-LD where struct ore_components holds an array of ore_dev-pointers. (ore_dev is newly defined and contains a struct osd_dev *od member) Each pointer in the array of pointers will point to a bigger user-defined dev_struct. That can be accessed by use of the container_of macro. In Exofs an __alloc_dev_table() function allocates the ore_dev-pointers array as well as an exofs_dev array, in one allocation and does the addresses dance to set everything pointing correctly. It still keeps the double allocation trick for the inodes round-robin view of the table. The device table is always allocated dynamically, also for the single device case. So it is unconditionally freed at umount. Signed-off-by: Boaz Harrosh --- include/scsi/osd_ore.h | 26 +++++++++++++++++++++++++- 1 file changed, 25 insertions(+), 1 deletion(-) (limited to 'include') diff --git a/include/scsi/osd_ore.h b/include/scsi/osd_ore.h index e4d550faa7c9..8fefdfbb1ced 100644 --- a/include/scsi/osd_ore.h +++ b/include/scsi/osd_ore.h @@ -44,6 +44,10 @@ struct ore_layout { unsigned group_count; }; +struct ore_dev { + struct osd_dev *od; +}; + struct ore_components { unsigned numdevs; /* Num of devices in array */ /* If @single_comp == EC_SINGLE_COMP, @comps points to a single @@ -53,9 +57,29 @@ struct ore_components { EC_SINGLE_COMP = 0, EC_MULTPLE_COMPS = 0xffffffff } single_comp; struct ore_comp *comps; - struct osd_dev **ods; /* osd_dev array */ + + /* Array of pointers to ore_dev-* . User will usually have these pointed + * too a bigger struct which contain an "ore_dev ored" member and use + * container_of(oc->ods[i], struct foo_dev, ored) to access the bigger + * structure. + */ + struct ore_dev **ods; }; +/* ore_comp_dev Recievies a logical device index */ +static inline struct osd_dev *ore_comp_dev( + const struct ore_components *oc, unsigned i) +{ + BUG_ON(oc->numdevs <= i); + return oc->ods[i]->od; +} + +static inline void ore_comp_set_dev( + struct ore_components *oc, unsigned i, struct osd_dev *od) +{ + oc->ods[i]->od = od; +} + struct ore_striping_info { u64 obj_offset; u64 group_length; -- cgit