diff options
Diffstat (limited to 'src/H5Fsuper.c')
-rw-r--r-- | src/H5Fsuper.c | 87 |
1 files changed, 70 insertions, 17 deletions
diff --git a/src/H5Fsuper.c b/src/H5Fsuper.c index 4c12cb9..d30434d 100644 --- a/src/H5Fsuper.c +++ b/src/H5Fsuper.c @@ -457,23 +457,46 @@ H5F__super_read(H5F_t *f, hid_t meta_dxpl_id, hid_t raw_dxpl_id, hbool_t initial if(NULL == (sblock = (H5F_super_t *)H5AC_protect(f, meta_dxpl_id, H5AC_SUPERBLOCK, (haddr_t)0, &udata, rw_flags))) HGOTO_ERROR(H5E_FILE, H5E_CANTPROTECT, FAIL, "unable to load superblock") - /* Upgrade low bound to at least V18 when encountering version 2 superblock */ + /* + * When opening a file with SWMR-write access, the library will first + * check to ensure that superblock version 3 is used. Otherwise fail + * file open. + * + * Then the library will upgrade the file's low_bound depending on + * superblock version as follows: + * --version 0 or 1: no change to low_bound + * --version 2: upgrade low_bound to at least V18 + * --version 3: upgrade low_bound to at least V110 + * + * Upgrading low_bound will give the best format versions available for + * that superblock version. Due to the possible upgrade, the fapl returned + * from H5Fget_access_plist() might indicate a low_bound higher than what + * the user originally set. + * + * After upgrading low_bound, the library will check to ensure that the + * superblock version does not exceed the version allowed by high_bound. + * Otherise fail file open. + * + * For details, please see RFC:Setting Bounds for Object Creation in HDF5 1.10.0. + */ + + /* Check to ensure that superblock version 3 is used for SWMR-write access */ + if(H5F_INTENT(f) & H5F_ACC_SWMR_WRITE) { + if(sblock->super_vers < HDF5_SUPERBLOCK_VERSION_3) + HGOTO_ERROR(H5E_FILE, H5E_BADVALUE, FAIL, "superblock version for SWMR is less than 3") + } + + /* Upgrade low_bound to at least V18 when encountering version 2 superblock */ if(sblock->super_vers == HDF5_SUPERBLOCK_VERSION_2) f->shared->low_bound = MAX(H5F_LIBVER_V18, f->shared->low_bound); - /* Upgrade low bound to at least V110 when encountering version 3 superblock or SWMR_WRITE */ - if((sblock->super_vers >= HDF5_SUPERBLOCK_VERSION_3) || (H5F_INTENT(f) & H5F_ACC_SWMR_WRITE)) + /* Upgrade low_bound to at least V110 when encountering version 3 superblock */ + if(sblock->super_vers >= HDF5_SUPERBLOCK_VERSION_3) f->shared->low_bound = MAX(H5F_LIBVER_V110, f->shared->low_bound); - /* File bound check */ + /* Version bounds check */ if(sblock->super_vers > HDF5_superblock_ver_bounds[f->shared->high_bound]) - HGOTO_ERROR(H5E_FILE, H5E_BADVALUE, FAIL, "superblock version out of bounds (high bound)") - - /* SWMR requires at least superblock version 3 */ - if(H5F_INTENT(f) & H5F_ACC_SWMR_WRITE) { - if(sblock->super_vers < HDF5_superblock_ver_bounds[f->shared->low_bound]) - HGOTO_ERROR(H5E_FILE, H5E_BADVALUE, FAIL, "superblock version out of bounds (low bound)") - } + HGOTO_ERROR(H5E_FILE, H5E_BADVALUE, FAIL, "superblock version exceeds high bound") /* Pin the superblock in the cache */ if(H5AC_pin_protected_entry(sblock) < 0) @@ -833,9 +856,9 @@ H5F__super_read(H5F_t *f, hid_t meta_dxpl_id, hid_t raw_dxpl_id, hbool_t initial hbool_t rw = ((rw_flags & H5AC__READ_ONLY_FLAG) == 0); H5O_mdci_t mdci_msg; - /* Message exists but file format version high bound does not allow it */ + /* Message exists but version high bound does not allow it */ if(f->shared->high_bound < H5F_LIBVER_V110) - HGOTO_ERROR(H5E_FILE, H5E_CANTGET, FAIL, "file format version out of bound for metadata cache image") + HGOTO_ERROR(H5E_FILE, H5E_CANTGET, FAIL, "format version out of bound for metadata cache image") /* if the metadata cache image superblock extension message exists, * read its contents and pass the data on to the metadata cache. @@ -1037,6 +1060,36 @@ H5F__super_init(H5F_t *f, hid_t dxpl_id) f->shared->fs_page_size == H5F_FILE_SPACE_PAGE_SIZE_DEF)) non_default_fs_settings = TRUE; + /* + * When creating a file with write access, the library will: + * -- set superblock version to 0, 1 or 2 based on feature enabled + * -- no change to low_bound + * When creating a file with SWMR-write access, the library will: + * (See explanation (#) below.) + * -- set superblock version to 3 + * -- upgrade low_bound to at least V110 + * + * Then the library will finalize superblock version to that allowed by + * low_bound if that is higher. + * Lastly, the library will check to ensure the superblock version does not + * exceed the version allowed by high_bound. Otherwise fail file open. + * + * For details, please see RFC:Setting Bounds for Object Creation in HDF5 1.10.0. + * + * (#) + * Version 3 superblock is introduced in 1.10 for SWMR due to the problem of + * the status_flags field in the superblock. The problem is discussed in + * jira issue SWMR-79 and also in the RFC: File Format Changes in HDF5 1.10.0. + * The file's low_bound is upgraded for SWMR so that the library will + * use the best format versions available in 1.10. + * Due to the possible upgrade, the fapl returned from H5Fget_access_plist() + * might indicate a low_bound higher than what the user originally set. + */ + + /* + * Creating a file with SWMR-write access will + * upgrade superblock version and low_bound + */ if(H5F_INTENT(f) & H5F_ACC_SWMR_WRITE) { super_vers = HDF5_SUPERBLOCK_VERSION_3; f->shared->low_bound = MAX(H5F_LIBVER_V110, f->shared->low_bound); @@ -1060,10 +1113,10 @@ H5F__super_init(H5F_t *f, hid_t dxpl_id) else if(sblock->btree_k[H5B_CHUNK_ID] != HDF5_BTREE_CHUNK_IK_DEF) super_vers = HDF5_SUPERBLOCK_VERSION_1; - /* Upgrade to the version indicated by the file's low bound if higher */ + /* Finalize superblock version to that allowed by the file's low bound if higher */ super_vers = MAX(super_vers, HDF5_superblock_ver_bounds[f->shared->low_bound]); - /* File bound check */ + /* Version bounds check */ if(super_vers > HDF5_superblock_ver_bounds[f->shared->high_bound]) HGOTO_ERROR(H5E_FILE, H5E_BADVALUE, FAIL, "superblock version out of bounds") @@ -1091,8 +1144,8 @@ H5F__super_init(H5F_t *f, hid_t dxpl_id) /* Sanity check the userblock size vs. the file's allocation alignment */ if(userblock_size > 0) { - /* Set up the alignment to use for page or aggr fs */ - hsize_t alignment = H5F_PAGED_AGGR(f) ? f->shared->fs_page_size : f->shared->alignment; + /* Set up the alignment to use for page or aggr fs */ + hsize_t alignment = H5F_PAGED_AGGR(f) ? f->shared->fs_page_size : f->shared->alignment; if(userblock_size < alignment) HGOTO_ERROR(H5E_FILE, H5E_BADVALUE, FAIL, "userblock size must be > file object alignment") |