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				.Dd April 6, 2021
				.Dt VNODE_PAGER_SETSIZE 9
				.Os
				.Sh NAME
				.Nm vnode_pager_setsize
				.Nd "notify the VM system about updates in the file size"
				.Sh SYNOPSIS
				bcrUnsubmitted Done Inline Actions How about "Notify the VM system about updates in the file size"? bcr: How about "Notify the VM system about updates in the file size"?
				.In sys/param.h
				.In vm/vm.h
				.In vm/vm_extern.h
				.Ft void
				.Fn vnode_pager_setsize "struct vnode *vp" "vm_ooffset_t nsize"
				.Sh DESCRIPTION
				.Nm
				lets the VM system know about a change in size for a file.
				Content beyond the new EOF specified by the
				.Fa nsize
				argument will be purged from the cache.
				This function is useful for use within file system code to implement
				truncation in
				.Xr VOP_SETATTR 9 .
				.Sh IMPLEMENTATION NOTES
				In case the new EOF specified by the
				.Fa nsize
				argument is not aligned to page boundaries,
				partial-page area starting beyond the EOF will be zeroed.
				In partial-page area,
				for content occupying whole blocks within block
				boundaries,
				the dirty bits for the corresponding blocks will be cleared.
				.Sh LOCKING
				Writer lock of the VM object of
				.Fa vp
				will be held within the function.
				.Sh SEE ALSO
				.Xr vnode 9
				.Sh HISTORY
				The
				.Nm
				manual page first appeared in
				.Fx 14 .
				.Sh AUTHORS
				This
				manual page was written by
				.An Ka Ho Ng Aq Mt khng@FreeBSD.org .