diff --git a/libraries/persistent_store/fuzz/src/store.rs b/libraries/persistent_store/fuzz/src/store.rs index a008a4e..c18eb51 100644 --- a/libraries/persistent_store/fuzz/src/store.rs +++ b/libraries/persistent_store/fuzz/src/store.rs @@ -133,7 +133,7 @@ impl<'a> Fuzzer<'a> { page_size: 1 << self.entropy.read_range(5, 12), max_word_writes: 2, max_page_erases: self.entropy.read_range(0, 50000), - strict_write: true, + strict_mode: true, }; let num_pages = self.entropy.read_range(3, 64); self.record(StatKey::PageSize, options.page_size); @@ -156,7 +156,7 @@ impl<'a> Fuzzer<'a> { if self.debug { println!("Start with dirty storage."); } - options.strict_write = false; + options.strict_mode = false; let storage = BufferStorage::new(storage, options); StoreDriver::Off(StoreDriverOff::new_dirty(storage)) } else if self.entropy.read_bit() { diff --git a/libraries/persistent_store/src/buffer.rs b/libraries/persistent_store/src/buffer.rs index 0059826..ae35089 100644 --- a/libraries/persistent_store/src/buffer.rs +++ b/libraries/persistent_store/src/buffer.rs @@ -23,9 +23,9 @@ use alloc::vec; /// for tests and fuzzing, for which it has dedicated functionalities. /// /// This storage tracks how many times words are written between page erase cycles, how many times -/// pages are erased, and whether an operation flips bits in the wrong direction (optional). -/// Operations panic if those conditions are broken. This storage also permits to interrupt -/// operations for inspection or to corrupt the operation. +/// pages are erased, and whether an operation flips bits in the wrong direction. Operations panic +/// if those conditions are broken (optional). This storage also permits to interrupt operations for +/// inspection or to corrupt the operation. #[derive(Clone)] pub struct BufferStorage { /// Content of the storage. @@ -59,8 +59,13 @@ pub struct BufferOptions { /// How many times a page can be erased. pub max_page_erases: usize, - /// Whether bits cannot be written from 0 to 1. - pub strict_write: bool, + /// Whether the storage should check the flash invariant. + /// + /// When set, the following conditions would panic: + /// - A bit is written from 0 to 1. + /// - A word is written more than `max_word_writes`. + /// - A page is erased more than `max_page_erases`. + pub strict_mode: bool, } /// Corrupts a slice given actual and expected value. @@ -214,7 +219,10 @@ impl BufferStorage { /// /// Panics if the maximum number of erase cycles per page is reached. fn incr_page_erases(&mut self, page: usize) { - assert!(self.page_erases[page] < self.max_page_erases()); + // Check that pages are not erased too many times. + if self.options.strict_mode { + assert!(self.page_erases[page] < self.max_page_erases()); + } self.page_erases[page] += 1; let num_words = self.page_size() / self.word_size(); for word in 0..num_words { @@ -252,7 +260,10 @@ impl BufferStorage { continue; } let word = index / word_size + i; - assert!(self.word_writes[word] < self.max_word_writes()); + // Check that words are not written too many times. + if self.options.strict_mode { + assert!(self.word_writes[word] < self.max_word_writes()); + } self.word_writes[word] += 1; } } @@ -306,8 +317,8 @@ impl Storage for BufferStorage { self.interruption.tick(&operation)?; // Check and update counters. self.incr_word_writes(range.start, value, value); - // Check strict write. - if self.options.strict_write { + // Check that bits are correctly flipped. + if self.options.strict_mode { for (byte, &val) in range.clone().zip(value.iter()) { assert_eq!(self.storage[byte] & val, val); } @@ -472,7 +483,7 @@ mod tests { page_size: 16, max_word_writes: 2, max_page_erases: 3, - strict_write: true, + strict_mode: true, }; // Those words are decreasing bit patterns. Bits are only changed from 1 to 0 and at least one // bit is changed. diff --git a/libraries/persistent_store/src/store.rs b/libraries/persistent_store/src/store.rs index a3e084b..2559485 100644 --- a/libraries/persistent_store/src/store.rs +++ b/libraries/persistent_store/src/store.rs @@ -1257,7 +1257,7 @@ mod tests { page_size: self.page_size, max_word_writes: self.max_word_writes, max_page_erases: self.max_page_erases, - strict_write: true, + strict_mode: true, }; StoreDriverOff::new(options, self.num_pages) }