From 02eed0f8f2748fd7579f69e5373445b52b2b8754 Mon Sep 17 00:00:00 2001 From: AKASHI Takahiro Date: Mon, 17 Oct 2016 13:56:58 +0900 Subject: [PATCH 1/9] kexec: exntend the semantics of kexec_iomem_for_each_line The current kexec_iomem_for_each_line() counts up all the lines for which a callback function returns zero(0) or positive, and otherwise it stops further scanning. This behavior is incovenient in some cases. For instance, on arm64, we want to count up "System RAM" entries, but need to skip "reserved" entries. So this patch extends the semantics so that we will continue to scan succeeding entries but not count lines for which a callback function returns positive. The current users of kexec_iomem_for_each_line(), arm, sh and x86, will not be affected by this change because * arm The callback function only returns -1 or 0, and the return value of kexec_iomem_for_each_line() will never be used. * sh, x86 The callback function may return (-1 for sh,) 0 or 1, but always returns 1 once we have reached the maximum number of entries allowed. Even so the current kexec_iomem_for_each_line() counts them up. This change actually fixes this bug. Upstream-Status: Backport [https://git.linaro.org/people/takahiro.akashi/kexec-tools.git] Signed-off-by: AKASHI Takahiro Signed-off-by: He Zhe --- kexec/kexec-iomem.c | 15 ++++++++++----- 1 file changed, 10 insertions(+), 5 deletions(-) diff --git a/kexec/kexec-iomem.c b/kexec/kexec-iomem.c index 485a2e8..0a0277a 100644 --- a/kexec/kexec-iomem.c +++ b/kexec/kexec-iomem.c @@ -18,6 +18,9 @@ * Iterate over each line in the file returned by proc_iomem(). If match is * NULL or if the line matches with our match-pattern then call the * callback if non-NULL. + * If match is NULL, callback should return a negative if error. + * Otherwise the interation goes on, incrementing nr but only if callback + * returns 0 (matched). * * Return the number of lines matched. */ @@ -37,7 +40,7 @@ int kexec_iomem_for_each_line(char *match, char *str; int consumed; int count; - int nr = 0; + int nr = 0, ret; fp = fopen(iomem, "r"); if (!fp) @@ -50,11 +53,13 @@ int kexec_iomem_for_each_line(char *match, str = line + consumed; size = end - start + 1; if (!match || memcmp(str, match, strlen(match)) == 0) { - if (callback - && callback(data, nr, str, start, size) < 0) { - break; + if (callback) { + ret = callback(data, nr, str, start, size); + if (ret < 0) + break; + else if (ret == 0) + nr++; } - nr++; } } -- 1.9.1