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author | Daniel De Graaf <dgdegra@tycho.nsa.gov> | 2011-02-03 12:19:04 -0500 |
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committer | Konrad Rzeszutek Wilk <konrad.wilk@oracle.com> | 2011-02-14 14:16:17 -0500 |
commit | bdc612dc6903c4ea06e40d02f84ad5e25d93459d (patch) | |
tree | f7f3e3272b21ae3c6015e86f9c1f7be31534704d /include | |
parent | dd3140588d9551235ebc2a0dacdca098e7677573 (diff) | |
download | op-kernel-dev-bdc612dc6903c4ea06e40d02f84ad5e25d93459d.zip op-kernel-dev-bdc612dc6903c4ea06e40d02f84ad5e25d93459d.tar.gz |
xen/gntalloc,gntdev: Add unmap notify ioctl
This ioctl allows the users of a shared page to be notified when
the other end exits abnormally.
[v2: updated description in structs]
Signed-off-by: Daniel De Graaf <dgdegra@tycho.nsa.gov>
Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
Diffstat (limited to 'include')
-rw-r--r-- | include/xen/gntalloc.h | 32 | ||||
-rw-r--r-- | include/xen/gntdev.h | 31 |
2 files changed, 63 insertions, 0 deletions
diff --git a/include/xen/gntalloc.h b/include/xen/gntalloc.h index bc3b85e..76bd580 100644 --- a/include/xen/gntalloc.h +++ b/include/xen/gntalloc.h @@ -47,4 +47,36 @@ struct ioctl_gntalloc_dealloc_gref { /* Number of references to unmap */ uint32_t count; }; + +/* + * Sets up an unmap notification within the page, so that the other side can do + * cleanup if this side crashes. Required to implement cross-domain robust + * mutexes or close notification on communication channels. + * + * Each mapped page only supports one notification; multiple calls referring to + * the same page overwrite the previous notification. You must clear the + * notification prior to the IOCTL_GNTALLOC_DEALLOC_GREF if you do not want it + * to occur. + */ +#define IOCTL_GNTALLOC_SET_UNMAP_NOTIFY \ +_IOC(_IOC_NONE, 'G', 7, sizeof(struct ioctl_gntalloc_unmap_notify)) +struct ioctl_gntalloc_unmap_notify { + /* IN parameters */ + /* Offset in the file descriptor for a byte within the page (same as + * used in mmap). If using UNMAP_NOTIFY_CLEAR_BYTE, this is the byte to + * be cleared. Otherwise, it can be any byte in the page whose + * notification we are adjusting. + */ + uint64_t index; + /* Action(s) to take on unmap */ + uint32_t action; + /* Event channel to notify */ + uint32_t event_channel_port; +}; + +/* Clear (set to zero) the byte specified by index */ +#define UNMAP_NOTIFY_CLEAR_BYTE 0x1 +/* Send an interrupt on the indicated event channel */ +#define UNMAP_NOTIFY_SEND_EVENT 0x2 + #endif /* __LINUX_PUBLIC_GNTALLOC_H__ */ diff --git a/include/xen/gntdev.h b/include/xen/gntdev.h index eb23f41..5304bd3 100644 --- a/include/xen/gntdev.h +++ b/include/xen/gntdev.h @@ -116,4 +116,35 @@ struct ioctl_gntdev_set_max_grants { uint32_t count; }; +/* + * Sets up an unmap notification within the page, so that the other side can do + * cleanup if this side crashes. Required to implement cross-domain robust + * mutexes or close notification on communication channels. + * + * Each mapped page only supports one notification; multiple calls referring to + * the same page overwrite the previous notification. You must clear the + * notification prior to the IOCTL_GNTALLOC_DEALLOC_GREF if you do not want it + * to occur. + */ +#define IOCTL_GNTDEV_SET_UNMAP_NOTIFY \ +_IOC(_IOC_NONE, 'G', 7, sizeof(struct ioctl_gntdev_unmap_notify)) +struct ioctl_gntdev_unmap_notify { + /* IN parameters */ + /* Offset in the file descriptor for a byte within the page (same as + * used in mmap). If using UNMAP_NOTIFY_CLEAR_BYTE, this is the byte to + * be cleared. Otherwise, it can be any byte in the page whose + * notification we are adjusting. + */ + uint64_t index; + /* Action(s) to take on unmap */ + uint32_t action; + /* Event channel to notify */ + uint32_t event_channel_port; +}; + +/* Clear (set to zero) the byte specified by index */ +#define UNMAP_NOTIFY_CLEAR_BYTE 0x1 +/* Send an interrupt on the indicated event channel */ +#define UNMAP_NOTIFY_SEND_EVENT 0x2 + #endif /* __LINUX_PUBLIC_GNTDEV_H__ */ |