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    Subject[PATCH v12 02/12] livepatch: Helper macros to define livepatch structures
    Date
    The definition of struct klp_func might be a bit confusing.
    The original function is defined by name as a string.
    The new function is defined by name as a function pointer
    casted to unsigned long.

    This patch adds helper macros that hide the different types.
    The functions are defined just by the name. For example:

    static struct klp_func funcs[] = {
    {
    .old_name = "function_A",
    .new_addr = (unsigned long)livepatch_function_A,
    }, {
    .old_name = "function_B",
    .new_addr = (unsigned long)livepatch_function_B,
    }, { }
    };

    can be defined as:

    static struct klp_func funcs[] = {
    KLP_FUNC(function_A,
    livepatch_function_A),
    KLP_FUNC(function_B,
    livepatch_function_B),
    KLP_FUNC_END
    };

    Just for completeness, this patch adds similar macros to define
    struct klp_object. For example,

    static struct klp_object objs[] = {
    {
    /* name being NULL means vmlinux */
    .funcs = funcs_vmlinux,
    }, {
    .name = "module_A",
    .funcs = funcs_module_A,
    }, {
    .name = "module_B",
    .funcs = funcs_module_B,
    }, { }
    };

    can be defined as:

    static struct klp_object objs[] = {
    KLP_VMLINUX(funcs_vmlinux),
    KLP_OBJECT(module_A,
    funcs_module_A),
    KLP_OBJECT(module_B,
    funcs_module_B),
    KLP_OBJECT_END
    };

    Signed-off-by: Petr Mladek <pmladek@suse.com>
    ---
    include/linux/livepatch.h | 40 ++++++++++++++++++++
    samples/livepatch/livepatch-callbacks-demo.c | 55 +++++++++++-----------------
    samples/livepatch/livepatch-sample.c | 13 +++----
    samples/livepatch/livepatch-shadow-fix1.c | 20 ++++------
    samples/livepatch/livepatch-shadow-fix2.c | 20 ++++------
    5 files changed, 83 insertions(+), 65 deletions(-)

    diff --git a/include/linux/livepatch.h b/include/linux/livepatch.h
    index 817a737b49e8..1163742b27c0 100644
    --- a/include/linux/livepatch.h
    +++ b/include/linux/livepatch.h
    @@ -152,6 +152,46 @@ struct klp_patch {
    struct completion finish;
    };

    +#define KLP_FUNC(_old_func, _new_func) { \
    + .old_name = #_old_func, \
    + .new_addr = (unsigned long)(_new_func), \
    + }
    +#define KLP_FUNC_POS(_old_func, _new_func, _sympos) { \
    + .old_name = #_old_func, \
    + .new_addr = (unsigned long)_new_func, \
    + .sympos = _sympos, \
    + }
    +#define KLP_FUNC_END { }
    +
    +#define KLP_OBJECT(_obj, _funcs) { \
    + .name = #_obj, \
    + .funcs = _funcs, \
    + }
    +#define KLP_OBJECT_CALLBACKS(_obj, _funcs, \
    + _pre_patch, _post_patch, \
    + _pre_unpatch, _post_unpatch) { \
    + .name = #_obj, \
    + .funcs = _funcs, \
    + .callbacks.pre_patch = _pre_patch, \
    + .callbacks.post_patch = _post_patch, \
    + .callbacks.pre_unpatch = _pre_unpatch, \
    + .callbacks.post_unpatch = _post_unpatch, \
    + }
    +/* name being NULL means vmlinux */
    +#define KLP_VMLINUX(_funcs) { \
    + .funcs = _funcs, \
    + }
    +#define KLP_VMLINUX_CALLBACKS(_funcs, \
    + _pre_patch, _post_patch, \
    + _pre_unpatch, _post_unpatch) { \
    + .funcs = _funcs, \
    + .callbacks.pre_patch = _pre_patch, \
    + .callbacks.post_patch = _post_patch, \
    + .callbacks.pre_unpatch = _pre_unpatch, \
    + .callbacks.post_unpatch = _post_unpatch, \
    + }
    +#define KLP_OBJECT_END { }
    +
    #define klp_for_each_object(patch, obj) \
    for (obj = patch->objs; obj->funcs || obj->name; obj++)

    diff --git a/samples/livepatch/livepatch-callbacks-demo.c b/samples/livepatch/livepatch-callbacks-demo.c
    index 4b1aec474bb7..001a0c672251 100644
    --- a/samples/livepatch/livepatch-callbacks-demo.c
    +++ b/samples/livepatch/livepatch-callbacks-demo.c
    @@ -147,45 +147,34 @@ static void patched_work_func(struct work_struct *work)
    }

    static struct klp_func no_funcs[] = {
    - { }
    + KLP_FUNC_END
    };

    static struct klp_func busymod_funcs[] = {
    - {
    - .old_name = "busymod_work_func",
    - .new_addr = (unsigned long)patched_work_func,
    - }, { }
    + KLP_FUNC(busymod_work_func,
    + patched_work_func),
    + KLP_FUNC_END
    };

    static struct klp_object objs[] = {
    - {
    - .name = NULL, /* vmlinux */
    - .funcs = no_funcs,
    - .callbacks = {
    - .pre_patch = pre_patch_callback,
    - .post_patch = post_patch_callback,
    - .pre_unpatch = pre_unpatch_callback,
    - .post_unpatch = post_unpatch_callback,
    - },
    - }, {
    - .name = "livepatch_callbacks_mod",
    - .funcs = no_funcs,
    - .callbacks = {
    - .pre_patch = pre_patch_callback,
    - .post_patch = post_patch_callback,
    - .pre_unpatch = pre_unpatch_callback,
    - .post_unpatch = post_unpatch_callback,
    - },
    - }, {
    - .name = "livepatch_callbacks_busymod",
    - .funcs = busymod_funcs,
    - .callbacks = {
    - .pre_patch = pre_patch_callback,
    - .post_patch = post_patch_callback,
    - .pre_unpatch = pre_unpatch_callback,
    - .post_unpatch = post_unpatch_callback,
    - },
    - }, { }
    + KLP_VMLINUX_CALLBACKS(no_funcs,
    + pre_patch_callback,
    + post_patch_callback,
    + pre_unpatch_callback,
    + post_unpatch_callback),
    + KLP_OBJECT_CALLBACKS(livepatch_callbacks_mod,
    + no_funcs,
    + pre_patch_callback,
    + post_patch_callback,
    + pre_unpatch_callback,
    + post_unpatch_callback),
    + KLP_OBJECT_CALLBACKS(livepatch_callbacks_busymod,
    + busymod_funcs,
    + pre_patch_callback,
    + post_patch_callback,
    + pre_unpatch_callback,
    + post_unpatch_callback),
    + KLP_OBJECT_END
    };

    static struct klp_patch patch = {
    diff --git a/samples/livepatch/livepatch-sample.c b/samples/livepatch/livepatch-sample.c
    index e470a052fb77..de30d1ba4791 100644
    --- a/samples/livepatch/livepatch-sample.c
    +++ b/samples/livepatch/livepatch-sample.c
    @@ -49,17 +49,14 @@ static int livepatch_cmdline_proc_show(struct seq_file *m, void *v)
    }

    static struct klp_func funcs[] = {
    - {
    - .old_name = "cmdline_proc_show",
    - .new_addr = (unsigned long)livepatch_cmdline_proc_show,
    - }, { }
    + KLP_FUNC(cmdline_proc_show,
    + livepatch_cmdline_proc_show),
    + KLP_FUNC_END
    };

    static struct klp_object objs[] = {
    - {
    - /* name being NULL means vmlinux */
    - .funcs = funcs,
    - }, { }
    + KLP_VMLINUX(funcs),
    + KLP_OBJECT_END
    };

    static struct klp_patch patch = {
    diff --git a/samples/livepatch/livepatch-shadow-fix1.c b/samples/livepatch/livepatch-shadow-fix1.c
    index ede0de7abe40..8f337b4a9108 100644
    --- a/samples/livepatch/livepatch-shadow-fix1.c
    +++ b/samples/livepatch/livepatch-shadow-fix1.c
    @@ -128,21 +128,17 @@ void livepatch_fix1_dummy_free(struct dummy *d)
    }

    static struct klp_func funcs[] = {
    - {
    - .old_name = "dummy_alloc",
    - .new_addr = (unsigned long)livepatch_fix1_dummy_alloc,
    - },
    - {
    - .old_name = "dummy_free",
    - .new_addr = (unsigned long)livepatch_fix1_dummy_free,
    - }, { }
    + KLP_FUNC(dummy_alloc,
    + livepatch_fix1_dummy_alloc),
    + KLP_FUNC(dummy_free,
    + livepatch_fix1_dummy_free),
    + KLP_FUNC_END
    };

    static struct klp_object objs[] = {
    - {
    - .name = "livepatch_shadow_mod",
    - .funcs = funcs,
    - }, { }
    + KLP_OBJECT(livepatch_shadow_mod,
    + funcs),
    + KLP_OBJECT_END
    };

    static struct klp_patch patch = {
    diff --git a/samples/livepatch/livepatch-shadow-fix2.c b/samples/livepatch/livepatch-shadow-fix2.c
    index 035ee0ef387f..e8c0c0467bc0 100644
    --- a/samples/livepatch/livepatch-shadow-fix2.c
    +++ b/samples/livepatch/livepatch-shadow-fix2.c
    @@ -105,21 +105,17 @@ void livepatch_fix2_dummy_free(struct dummy *d)
    }

    static struct klp_func funcs[] = {
    - {
    - .old_name = "dummy_check",
    - .new_addr = (unsigned long)livepatch_fix2_dummy_check,
    - },
    - {
    - .old_name = "dummy_free",
    - .new_addr = (unsigned long)livepatch_fix2_dummy_free,
    - }, { }
    + KLP_FUNC(dummy_check,
    + livepatch_fix2_dummy_check),
    + KLP_FUNC(dummy_free,
    + livepatch_fix2_dummy_free),
    + KLP_FUNC_END
    };

    static struct klp_object objs[] = {
    - {
    - .name = "livepatch_shadow_mod",
    - .funcs = funcs,
    - }, { }
    + KLP_OBJECT(livepatch_shadow_mod,
    + funcs),
    + KLP_OBJECT_END
    };

    static struct klp_patch patch = {
    --
    2.13.7
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      Last update: 2018-08-28 16:39    [W:2.685 / U:0.296 seconds]
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