qemu - QEMU is a generic and open source machine & userspace emulator and virtualizer.

Age	Commit message (Collapse)	Author
2019-01-14	xen: add xenstore watcher infrastructure	Paul Durrant
	A Xen PV frontend communicates its state to the PV backend by writing to the 'state' key in the frontend area in xenstore. It is therefore necessary for a XenDevice implementation to be notified whenever the value of this key changes. This patch adds code to do this as follows: - an 'fd handler' is registered on the libxenstore handle which will be triggered whenever a 'watch' event occurs - primitives are added to xen-bus-helper to add or remove watch events - a list of Notifier objects is added to XenBus to provide a mechanism to call the appropriate 'watch handler' when its associated event occurs The xen-block implementation is extended with a 'frontend_changed' method, which calls as-yet stub 'connect' and 'disconnect' functions when the relevant frontend state transitions occur. A subsequent patch will supply a full implementation for these functions. Signed-off-by: Paul Durrant <paul.durrant@citrix.com> Reviewed-by: Anthony Perard <anthony.perard@citrix.com> Signed-off-by: Anthony PERARD <anthony.perard@citrix.com>
2019-01-14	xen: create xenstore areas for XenDevice-s	Paul Durrant
	This patch adds a new source module, xen-bus-helper.c, which builds on basic libxenstore primitives to provide functions to create (setting permissions appropriately) and destroy xenstore areas, and functions to 'printf' and 'scanf' nodes therein. The main xen-bus code then uses these primitives [1] to initialize and destroy the frontend and backend areas for a XenDevice during realize and unrealize respectively. The 'xen-block' implementation is extended with a 'get_name' method that returns the VBD number. This number is required to 'name' the xenstore areas. NOTE: An exit handler is also added to make sure the xenstore areas are cleaned up if QEMU terminates without devices being unrealized. [1] The 'scanf' functions are actually not yet needed, but they will be needed by code delivered in subsequent patches. Signed-off-by: Paul Durrant <paul.durrant@citrix.com> Reviewed-by: Anthony Perard <anthony.perard@citrix.com> Signed-off-by: Anthony PERARD <anthony.perard@citrix.com>