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USER_REGSET_WRITEBAC(9) Machine State USER_REGSET_WRITEBAC(9)

NAME

user_regset_writeback_fn - type of writeback function in struct user_regset

SYNOPSIS

typedef int user_regset_writeback_fn(struct task_struct * target, const struct user_regset * regset, int immediate);

ARGUMENTS

target

thread being examined

regset

regset being examined

immediate

zero if writeback at completion of next context switch is OK

DESCRIPTION

This call is optional; usually the pointer is NULL. When provided, there is some user memory associated with this regset´s hardware, such as memory backing cached register data on register window machines; the regset´s data controls what user memory is used (e.g. via the stack pointer value).

Write register data back to user memory. If the immediate flag is nonzero, it must be written to the user memory so uaccess or access_process_vm can see it when this call returns; if zero, then it must be written back by the time the task completes a context switch (as synchronized with wait_task_inactive). Return 0 on success or if there was nothing to do, -EFAULT for a memory problem (bad stack pointer or whatever), or -EIO for a hardware problem.

May 2024 Kernel Hackers Manual 2.6.