kernel/linux.git/lib/vdso/datastore.c, branch v7.1-rc5

vdso/timens: Move functions to new file

2026-03-26T14:44:22+00:00

As a preparation of the untangling of time namespaces and the vDSO, move the glue functions between those subsystems into a new file. While at it, switch the mutex lock and mmap_read_lock() in the vDSO namespace code to guard(). Signed-off-by: Thomas Weißschuh Signed-off-by: Thomas Gleixner Link: https://patch.msgid.link/20260326-vdso-timens-decoupling-v2-1-c82693a7775f@linutronix.de

vdso/datastore: Allocate data pages dynamically

2026-03-11T09:18:30+00:00

Allocating the data pages as part of the kernel image does not work on SPARC. The MMU will raise a fault when userspace tries to access them. Allocate the data pages through the page allocator instead. Unused pages in the vDSO VMA are still allocated to keep the virtual addresses aligned. Switch the mapping from PFNs to 'struct page' as that is required for dynamically allocated pages. This also aligns the allocation of the datapages with the code pages and is a prerequisite for mlockall() support. VM_MIXEDMAP is necessary for the call to vmf_insert_page() in the timens prefault path to work. The data pages need to be order-0, non-compound pages so that the mapping to userspace and the different orderings work. These pages are also used by the timekeeping, random pool and architecture initialization code. Some of these are running before the page allocator is available. To keep these subsytems working without changes, introduce early, statically data storage which will then replaced by the real one as soon as that is available. Signed-off-by: Thomas Weißschuh Signed-off-by: Thomas Gleixner Reviewed-by: Christophe Leroy (CS GROUP) Link: https://patch.msgid.link/20260304-vdso-sparc64-generic-2-v6-3-d8eb3b0e1410@linutronix.de

vdso/datastore: Drop inclusion of linux/mmap_lock.h

2026-03-11T09:18:30+00:00

This header is unnecessary and together with some upcoming changes would introduce compiler warnings. Signed-off-by: Thomas Weißschuh Signed-off-by: Thomas Gleixner Tested-by: Andreas Larsson Reviewed-by: Andreas Larsson Reviewed-by: Christophe Leroy (CS GROUP) Link: https://lore.kernel.org/lkml/20250916-mm-rcuwait-v1-1-39a3beea6ec3@linutronix.de/ Link: https://patch.msgid.link/20260304-vdso-sparc64-generic-2-v6-2-d8eb3b0e1410@linutronix.de

vdso/datastore: Reduce scope of some variables in vvar_fault()

2026-03-11T09:18:30+00:00

These variables are only used inside a single branch. Move their declarations there. Signed-off-by: Thomas Weißschuh Signed-off-by: Thomas Gleixner Tested-by: Andreas Larsson Reviewed-by: Andreas Larsson Reviewed-by: Christophe Leroy (CS GROUP) Link: https://patch.msgid.link/20260304-vdso-sparc64-generic-2-v6-1-d8eb3b0e1410@linutronix.de

vdso/datastore: Gate time data behind CONFIG_GENERIC_GETTIMEOFDAY

2025-09-04T09:23:49+00:00

When the generic vDSO does not provide time functions, as for example on riscv32, then the time data store is not necessary. Avoid allocating these time data pages when not used. Fixes: df7fcbefa710 ("vdso: Add generic time data storage") Signed-off-by: Thomas Weißschuh Signed-off-by: Thomas Gleixner Link: https://lore.kernel.org/all/20250826-vdso-cleanups-v1-1-d9b65750e49f@linutronix.de

mseal sysmap: generic vdso vvar mapping

2025-04-01T22:17:15+00:00

With the introduction of the generic vdso data storage the VM_SEALED_SYSMAP vm flag must be moved from the architecture specific _install_special_mapping() call [1] [2] which maps the vvar mapping to generic code. [1] https://lkml.kernel.org/r/20250305021711.3867874-4-jeffxu@google.com [2] https://lkml.kernel.org/r/20250305021711.3867874-5-jeffxu@google.com Link: https://lkml.kernel.org/r/20250311123326.2686682-2-hca@linux.ibm.com Signed-off-by: Heiko Carstens Reviewed-by: Lorenzo Stoakes Cc: Alexander Gordeev Cc: Christian Borntraeger Cc: Jeff Xu Cc: Liam Howlett Cc: Sven Schnelle Cc: Thomas Weißschuh Cc: Vasily Gorbik Signed-off-by: Andrew Morton

vdso: Rework struct vdso_time_data and introduce struct vdso_clock

2025-03-08T13:37:41+00:00

To support multiple PTP clocks, the VDSO data structure needs to be reworked. All clock specific data will end up in struct vdso_clock and in struct vdso_time_data there will be an array of VDSO clocks. Now that all preparatory changes are in place: Split the clock related struct members into a separate struct vdso_clock. Make sure all users are aware, that vdso_time_data is no longer initialized as an array and vdso_clock is now the array inside vdso_data. Remove the vdso_clock define, which mapped it to vdso_time_data for the transition. Signed-off-by: Anna-Maria Behnsen Signed-off-by: Nam Cao Signed-off-by: Thomas Weißschuh Signed-off-by: Thomas Gleixner Link: https://lore.kernel.org/all/20250303-vdso-clock-v1-19-c1b5c69a166f@linutronix.de

vdso/namespace: Rename timens_setup_vdso_data() to reflect new vdso_clock struct

2025-03-08T13:37:41+00:00

To support multiple PTP clocks, the VDSO data structure needs to be reworked. All clock specific data will end up in struct vdso_clock and in struct vdso_time_data there will be array of VDSO clocks. At the moment, vdso_clock is simply a define which maps vdso_clock to vdso_time_data. For time namespaces, vdso_time_data needs to be set up. But only the clock related part of the vdso_data thats requires this setup. To reflect the future struct vdso_clock, rename timens_setup_vdso_data() to timns_setup_vdso_clock_data(). No functional change. Signed-off-by: Anna-Maria Behnsen Signed-off-by: Nam Cao Signed-off-by: Thomas Weißschuh Signed-off-by: Thomas Gleixner Link: https://lore.kernel.org/all/20250303-vdso-clock-v1-13-c1b5c69a166f@linutronix.de

vdso: Remove remnants of architecture-specific time storage

2025-02-21T08:54:03+00:00

All users of the time releated parts of the vDSO are now using the generic storage implementation. Remove the therefore unnecessary compatibility accessor functions and symbols. Co-developed-by: Nam Cao Signed-off-by: Nam Cao Signed-off-by: Thomas Weißschuh Signed-off-by: Thomas Gleixner Link: https://lore.kernel.org/all/20250204-vdso-store-rng-v3-18-13a4669dfc8c@linutronix.de

vdso: Add generic architecture-specific data storage

2025-02-21T08:54:01+00:00

Some architectures need to expose architecture-specific data to the vDSO. Enable the generic vDSO storage mechanism to both store and map this data. Some architectures require more than a single page, like LoongArch, so prepare for that usecase, too. Signed-off-by: Thomas Weißschuh Signed-off-by: Thomas Gleixner Link: https://lore.kernel.org/all/20250204-vdso-store-rng-v3-7-13a4669dfc8c@linutronix.de