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author | Linus Torvalds <torvalds@linux-foundation.org> | 2011-11-07 09:11:16 -0800 |
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committer | Linus Torvalds <torvalds@linux-foundation.org> | 2011-11-07 09:11:16 -0800 |
commit | e0d65113a70f1dc514e625cc4e7a7485a4bf72df (patch) | |
tree | 7320a130dc304623f5cf4b5dd8f67fb1776225ca /fs/jffs2/compr.c | |
parent | cf5e15fbd72c13977720aa15b7b7e00e1d8fd8f2 (diff) | |
parent | 48e546b7f281f251893baa40769581fd15f085fb (diff) | |
download | op-kernel-dev-e0d65113a70f1dc514e625cc4e7a7485a4bf72df.zip op-kernel-dev-e0d65113a70f1dc514e625cc4e7a7485a4bf72df.tar.gz |
Merge git://git.infradead.org/mtd-2.6
* git://git.infradead.org/mtd-2.6: (226 commits)
mtd: tests: annotate as DANGEROUS in Kconfig
mtd: tests: don't use mtd0 as a default
mtd: clean up usage of MTD_DOCPROBE_ADDRESS
jffs2: add compr=lzo and compr=zlib options
jffs2: implement mount option parsing and compression overriding
mtd: nand: initialize ops.mode
mtd: provide an alias for the redboot module name
mtd: m25p80: don't probe device which has status of 'disabled'
mtd: nand_h1900 never worked
mtd: Add DiskOnChip G3 support
mtd: m25p80: add EON flash EN25Q32B into spi flash id table
mtd: mark block device queue as non-rotational
mtd: r852: make r852_pm_ops static
mtd: m25p80: add support for at25df321a spi data flash
mtd: mxc_nand: preset_v1_v2: unlock all NAND flash blocks
mtd: nand: switch `check_pattern()' to standard `memcmp()'
mtd: nand: invalidate cache on unaligned reads
mtd: nand: do not scan bad blocks with NAND_BBT_NO_OOB set
mtd: nand: wait to set BBT version
mtd: nand: scrub BBT on ECC errors
...
Fix up trivial conflicts:
- arch/arm/mach-at91/board-usb-a9260.c
Merged into board-usb-a926x.c
- drivers/mtd/maps/lantiq-flash.c
add_mtd_partitions -> mtd_device_register vs changed to use
mtd_device_parse_register.
Diffstat (limited to 'fs/jffs2/compr.c')
-rw-r--r-- | fs/jffs2/compr.c | 128 |
1 files changed, 91 insertions, 37 deletions
diff --git a/fs/jffs2/compr.c b/fs/jffs2/compr.c index de42470..5b6c9d1 100644 --- a/fs/jffs2/compr.c +++ b/fs/jffs2/compr.c @@ -53,6 +53,78 @@ static int jffs2_is_best_compression(struct jffs2_compressor *this, return 0; } +/* + * jffs2_selected_compress: + * @compr: Explicit compression type to use (ie, JFFS2_COMPR_ZLIB). + * If 0, just take the first available compression mode. + * @data_in: Pointer to uncompressed data + * @cpage_out: Pointer to returned pointer to buffer for compressed data + * @datalen: On entry, holds the amount of data available for compression. + * On exit, expected to hold the amount of data actually compressed. + * @cdatalen: On entry, holds the amount of space available for compressed + * data. On exit, expected to hold the actual size of the compressed + * data. + * + * Returns: the compression type used. Zero is used to show that the data + * could not be compressed; probably because we couldn't find the requested + * compression mode. + */ +static int jffs2_selected_compress(u8 compr, unsigned char *data_in, + unsigned char **cpage_out, u32 *datalen, u32 *cdatalen) +{ + struct jffs2_compressor *this; + int err, ret = JFFS2_COMPR_NONE; + uint32_t orig_slen, orig_dlen; + char *output_buf; + + output_buf = kmalloc(*cdatalen, GFP_KERNEL); + if (!output_buf) { + printk(KERN_WARNING "JFFS2: No memory for compressor allocation. Compression failed.\n"); + return ret; + } + orig_slen = *datalen; + orig_dlen = *cdatalen; + spin_lock(&jffs2_compressor_list_lock); + list_for_each_entry(this, &jffs2_compressor_list, list) { + /* Skip decompress-only and disabled modules */ + if (!this->compress || this->disabled) + continue; + + /* Skip if not the desired compression type */ + if (compr && (compr != this->compr)) + continue; + + /* + * Either compression type was unspecified, or we found our + * compressor; either way, we're good to go. + */ + this->usecount++; + spin_unlock(&jffs2_compressor_list_lock); + + *datalen = orig_slen; + *cdatalen = orig_dlen; + err = this->compress(data_in, output_buf, datalen, cdatalen); + + spin_lock(&jffs2_compressor_list_lock); + this->usecount--; + if (!err) { + /* Success */ + ret = this->compr; + this->stat_compr_blocks++; + this->stat_compr_orig_size += *datalen; + this->stat_compr_new_size += *cdatalen; + break; + } + } + spin_unlock(&jffs2_compressor_list_lock); + if (ret == JFFS2_COMPR_NONE) + kfree(output_buf); + else + *cpage_out = output_buf; + + return ret; +} + /* jffs2_compress: * @data_in: Pointer to uncompressed data * @cpage_out: Pointer to returned pointer to buffer for compressed data @@ -76,47 +148,23 @@ uint16_t jffs2_compress(struct jffs2_sb_info *c, struct jffs2_inode_info *f, uint32_t *datalen, uint32_t *cdatalen) { int ret = JFFS2_COMPR_NONE; - int compr_ret; + int mode, compr_ret; struct jffs2_compressor *this, *best=NULL; unsigned char *output_buf = NULL, *tmp_buf; uint32_t orig_slen, orig_dlen; uint32_t best_slen=0, best_dlen=0; - switch (jffs2_compression_mode) { + if (c->mount_opts.override_compr) + mode = c->mount_opts.compr; + else + mode = jffs2_compression_mode; + + switch (mode) { case JFFS2_COMPR_MODE_NONE: break; case JFFS2_COMPR_MODE_PRIORITY: - output_buf = kmalloc(*cdatalen,GFP_KERNEL); - if (!output_buf) { - printk(KERN_WARNING "JFFS2: No memory for compressor allocation. Compression failed.\n"); - goto out; - } - orig_slen = *datalen; - orig_dlen = *cdatalen; - spin_lock(&jffs2_compressor_list_lock); - list_for_each_entry(this, &jffs2_compressor_list, list) { - /* Skip decompress-only backwards-compatibility and disabled modules */ - if ((!this->compress)||(this->disabled)) - continue; - - this->usecount++; - spin_unlock(&jffs2_compressor_list_lock); - *datalen = orig_slen; - *cdatalen = orig_dlen; - compr_ret = this->compress(data_in, output_buf, datalen, cdatalen); - spin_lock(&jffs2_compressor_list_lock); - this->usecount--; - if (!compr_ret) { - ret = this->compr; - this->stat_compr_blocks++; - this->stat_compr_orig_size += *datalen; - this->stat_compr_new_size += *cdatalen; - break; - } - } - spin_unlock(&jffs2_compressor_list_lock); - if (ret == JFFS2_COMPR_NONE) - kfree(output_buf); + ret = jffs2_selected_compress(0, data_in, cpage_out, datalen, + cdatalen); break; case JFFS2_COMPR_MODE_SIZE: case JFFS2_COMPR_MODE_FAVOURLZO: @@ -174,22 +222,28 @@ uint16_t jffs2_compress(struct jffs2_sb_info *c, struct jffs2_inode_info *f, best->stat_compr_orig_size += best_slen; best->stat_compr_new_size += best_dlen; ret = best->compr; + *cpage_out = output_buf; } spin_unlock(&jffs2_compressor_list_lock); break; + case JFFS2_COMPR_MODE_FORCELZO: + ret = jffs2_selected_compress(JFFS2_COMPR_LZO, data_in, + cpage_out, datalen, cdatalen); + break; + case JFFS2_COMPR_MODE_FORCEZLIB: + ret = jffs2_selected_compress(JFFS2_COMPR_ZLIB, data_in, + cpage_out, datalen, cdatalen); + break; default: printk(KERN_ERR "JFFS2: unknown compression mode.\n"); } - out: + if (ret == JFFS2_COMPR_NONE) { *cpage_out = data_in; *datalen = *cdatalen; none_stat_compr_blocks++; none_stat_compr_size += *datalen; } - else { - *cpage_out = output_buf; - } return ret; } |