From d49567ea27ee32a7733f8c9b54eacdba10b1860d Mon Sep 17 00:00:00 2001 From: Artem Bityutskiy Date: Wed, 28 Jan 2009 14:19:43 +0200 Subject: mkfs.ubifs: support reserved space allocation UBIFS may reserve some amount of flash space for the super-user, ant this amount is stored in the superblock. Currently mkfs.ubifs always puts 0 there. This patch adds -R option which may be used to specify size of the reserved space. Signed-off-by: Artem Bityutskiy --- mkfs.ubifs/lpt.c | 1 + mkfs.ubifs/mkfs.ubifs.c | 52 ++++++++++++++++++++++++++++++++++++++++++------- mkfs.ubifs/ubifs.h | 3 +++ 3 files changed, 49 insertions(+), 7 deletions(-) diff --git a/mkfs.ubifs/lpt.c b/mkfs.ubifs/lpt.c index 48ae03f..c8fb22c 100644 --- a/mkfs.ubifs/lpt.c +++ b/mkfs.ubifs/lpt.c @@ -549,6 +549,7 @@ int create_lpt(struct ubifs_info *c) c->nhead_lnum = lnum; c->nhead_offs = ALIGN(len, c->min_io_size); + dbg_msg(1, "lpt_sz: %d", c->lpt_sz); dbg_msg(1, "space_bits: %d", c->space_bits); dbg_msg(1, "lpt_lnum_bits: %d", c->lpt_lnum_bits); dbg_msg(1, "lpt_offs_bits: %d", c->lpt_offs_bits); diff --git a/mkfs.ubifs/mkfs.ubifs.c b/mkfs.ubifs/mkfs.ubifs.c index 22cee8e..0775972 100644 --- a/mkfs.ubifs/mkfs.ubifs.c +++ b/mkfs.ubifs/mkfs.ubifs.c @@ -128,7 +128,7 @@ static struct inum_mapping **hash_table; /* Inode creation sequence number */ static unsigned long long creat_sqnum; -static const char *optstring = "d:r:m:o:D:h?vVe:c:g:f:P:k:x:X:j:l:j:U"; +static const char *optstring = "d:r:m:o:D:h?vVe:c:g:f:P:k:x:X:j:R:l:j:U:"; static const struct option longopts[] = { {"root", 1, NULL, 'r'}, @@ -142,6 +142,7 @@ static const struct option longopts[] = { {"version", 0, NULL, 'V'}, {"debug-level", 1, NULL, 'g'}, {"jrn-size", 1, NULL, 'j'}, + {"reserved", 1, NULL, 'R'}, {"compr", 1, NULL, 'x'}, {"favor-percent", 1, NULL, 'X'}, {"fanout", 1, NULL, 'f'}, @@ -162,6 +163,7 @@ static const char *helptext = "-c, --max-leb-cnt=COUNT maximum logical erase block count\n" "-o, --output=FILE output to FILE\n" "-j, --jrn-size=SIZE journal size\n" +"-R, --reserved=SIZE how much space should be reserved for the super-user\n" "-x, --compr=TYPE compression type - \"lzo\", \"favor_lzo\", \"zlib\" or\n" " \"none\" (default: \"lzo\")\n" "-X, --favor-percent may only be used with favor LZO compression and defines\n" @@ -188,7 +190,8 @@ static const char *helptext = "compressors, then it compares which compressor is better. If \"zlib\" compresses 20\n" "or more percent better than \"lzo\", mkfs.ubifs chooses \"lzo\", otherwise it chooses\n" "\"zlib\". The \"--favor-percent\" may specify arbitrary threshold instead of the\n" -"default 20%.\n"; +"default 20%.\n\n" +"The -R parameter specifies amount of bytes reserved for the super-user.\n"; /** * make_path - make a path name from a directory and a name. @@ -318,6 +321,32 @@ static int calc_min_log_lebs(unsigned long long max_bud_bytes) return log_lebs; } +/** + * add_space_overhead - add UBIFS overhead. + * @size: flash space which should be visible to the user + * + * UBIFS has overhead, and if we need to reserve @size bytes for the user data, + * we have to reserve more flash space, to compensate the overhead. This + * function calculates and returns the amount of physical flash space which + * should be reserved to provide @size bytes for the user. + */ +static long long add_space_overhead(long long size) +{ + int divisor, factor, f, max_idx_node_sz; + + /* + * Do the opposite to what the 'ubifs_reported_space()' kernel UBIFS + * function does. + */ + max_idx_node_sz = ubifs_idx_node_sz(c, c->fanout); + f = c->fanout > 3 ? c->fanout >> 1 : 2; + divisor = UBIFS_BLOCK_SIZE; + factor = UBIFS_MAX_DATA_NODE_SZ; + factor += (max_idx_node_sz * 3) / (f - 1); + size *= factor; + return size / divisor; +} + static inline int is_power_of_2(unsigned long long n) { return (n != 0 && ((n & (n - 1)) == 0)); @@ -376,8 +405,9 @@ static int validate_options(void) "least %d", tmp); tmp = calc_min_log_lebs(c->max_bud_bytes); if (c->log_lebs < calc_min_log_lebs(c->max_bud_bytes)) - return err_msg("too few log LEBs, expected at least %d", - tmp); + return err_msg("too few log LEBs, expected at least %d", tmp); + if (c->rp_size >= ((long long)c->leb_size * c->max_leb_cnt) / 2) + return err_msg("too much reserved space %lld", c->rp_size); return 0; } @@ -574,6 +604,11 @@ static int get_options(int argc, char**argv) if (c->max_bud_bytes <= 0) return err_msg("bad maximum amount of buds"); break; + case 'R': + c->rp_size = get_bytes(optarg); + if (c->rp_size < 0) + return err_msg("bad reserved bytes count"); + break; case 'U': squash_owner = 1; break; @@ -619,6 +654,10 @@ static int get_options(int argc, char**argv) c->log_lebs += 2; } + if (c->min_io_size < 8) + c->min_io_size = 8; + c->rp_size = add_space_overhead(c->rp_size); + if (verbose) { printf("mkfs.ubifs\n"); printf("\troot: %s\n", root); @@ -627,6 +666,7 @@ static int get_options(int argc, char**argv) printf("\tmax_leb_cnt: %d\n", c->max_leb_cnt); printf("\toutput: %s\n", output); printf("\tjrn_size: %llu\n", c->max_bud_bytes); + printf("\treserved: %llu\n", c->rp_size); switch (c->default_compr) { case UBIFS_COMPR_LZO: printf("\tcompr: lzo\n"); @@ -644,9 +684,6 @@ static int get_options(int argc, char**argv) printf("\torph_lebs: %d\n", c->orph_lebs); } - if (c->min_io_size < 8) - c->min_io_size = 8; - if (validate_options()) return -1; @@ -1859,6 +1896,7 @@ static int write_super(void) sup.lsave_cnt = cpu_to_le32(c->lsave_cnt); sup.fmt_version = cpu_to_le32(UBIFS_FORMAT_VERSION); sup.default_compr = cpu_to_le16(c->default_compr); + sup.rp_size = cpu_to_le64(c->rp_size); sup.time_gran = cpu_to_le32(DEFAULT_TIME_GRAN); uuid_generate_random(sup.uuid); if (verbose) { diff --git a/mkfs.ubifs/ubifs.h b/mkfs.ubifs/ubifs.h index 48a583c..79c7192 100644 --- a/mkfs.ubifs/ubifs.h +++ b/mkfs.ubifs/ubifs.h @@ -293,6 +293,8 @@ struct ubifs_znode * @dark_wm: LEB dark space watermark * * @gc_lnum: LEB number used for garbage collection + * @rp_size: reserved pool size + * * @space_bits: number of bits needed to record free or dirty space * @lpt_lnum_bits: number of bits needed to record a LEB number in the LPT * @lpt_offs_bits: number of bits needed to record an offset in the LPT @@ -365,6 +367,7 @@ struct ubifs_info int dark_wm; int gc_lnum; + long long rp_size; int space_bits; int lpt_lnum_bits; -- cgit v1.2.3