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See http://www.infradead.org/rpr.html X-Rspamd-Server: rspam01 X-Stat-Signature: xj6fuixtzcbboe99kdmbb3w6dhh6rsnp X-Rspam-User: X-Rspamd-Queue-Id: 0AE221C000E X-HE-Tag: 1743782514-486669 X-HE-Meta: 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 3R8tm48+ 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 X-Bogosity: Ham, tests=bogofilter, spamicity=0.000000, version=1.2.4 Sender: owner-linux-mm@kvack.org Precedence: bulk X-Loop: owner-majordomo@kvack.org List-ID: List-Subscribe: List-Unsubscribe: From: David Woodhouse Introduce a pfn_first_valid() helper which takes a pointer to the PFN and updates it to point to the first valid PFN starting from that point, and returns true if a valid PFN was found. This largely mirrors pfn_valid(), calling into a pfn_section_first_valid() helper which is trivial for the !CONFIG_SPARSEMEM_VMEMMAP case, and in the VMEMMAP case will skip to the next subsection as needed. Signed-off-by: David Woodhouse Reviewed-by: Mike Rapoport (Microsoft) --- include/linux/mmzone.h | 59 ++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 59 insertions(+) diff --git a/include/linux/mmzone.h b/include/linux/mmzone.h index 32ecb5cadbaf..67cdf675a4b9 100644 --- a/include/linux/mmzone.h +++ b/include/linux/mmzone.h @@ -2074,11 +2074,37 @@ static inline int pfn_section_valid(struct mem_section *ms, unsigned long pfn) return usage ? test_bit(idx, usage->subsection_map) : 0; } + +static inline bool pfn_section_first_valid(struct mem_section *ms, unsigned long *pfn) +{ + struct mem_section_usage *usage = READ_ONCE(ms->usage); + int idx = subsection_map_index(*pfn); + unsigned long bit; + + if (!usage) + return false; + + if (test_bit(idx, usage->subsection_map)) + return true; + + /* Find the next subsection that exists */ + bit = find_next_bit(usage->subsection_map, SUBSECTIONS_PER_SECTION, idx); + if (bit == SUBSECTIONS_PER_SECTION) + return false; + + *pfn = (*pfn & PAGE_SECTION_MASK) + (bit * PAGES_PER_SUBSECTION); + return true; +} #else static inline int pfn_section_valid(struct mem_section *ms, unsigned long pfn) { return 1; } + +static inline bool pfn_section_first_valid(struct mem_section *ms, unsigned long *pfn) +{ + return true; +} #endif void sparse_init_early_section(int nid, struct page *map, unsigned long pnum, @@ -2127,6 +2153,39 @@ static inline int pfn_valid(unsigned long pfn) return ret; } + +static inline bool first_valid_pfn(unsigned long *p_pfn) +{ + unsigned long pfn = *p_pfn; + unsigned long nr = pfn_to_section_nr(pfn); + + rcu_read_lock_sched(); + + while (nr <= __highest_present_section_nr) { + struct mem_section *ms = __pfn_to_section(pfn); + + if (valid_section(ms) && + (early_section(ms) || pfn_section_first_valid(ms, &pfn))) { + *p_pfn = pfn; + rcu_read_unlock_sched(); + return true; + } + + /* Nothing left in this section? Skip to next section */ + nr++; + pfn = section_nr_to_pfn(nr); + } + + rcu_read_unlock_sched(); + + return false; +} + +#define for_each_valid_pfn(_pfn, _start_pfn, _end_pfn) \ + for ((_pfn) = (_start_pfn); \ + first_valid_pfn(&(_pfn)) && (_pfn) < (_end_pfn); \ + (_pfn)++) + #endif static inline int pfn_in_present_section(unsigned long pfn)