diff options
Diffstat (limited to 'fs/jffs2/compr.c')
| -rw-r--r-- | fs/jffs2/compr.c | 167 |
1 files changed, 113 insertions, 54 deletions
diff --git a/fs/jffs2/compr.c b/fs/jffs2/compr.c index f0294410868..4849a4c9a0e 100644 --- a/fs/jffs2/compr.c +++ b/fs/jffs2/compr.c @@ -2,15 +2,18 @@ * JFFS2 -- Journalling Flash File System, Version 2. * * Copyright © 2001-2007 Red Hat, Inc. - * Created by Arjan van de Ven <arjanv@redhat.com> - * + * Copyright © 2004-2010 David Woodhouse <dwmw2@infradead.org> * Copyright © 2004 Ferenc Havasi <havasi@inf.u-szeged.hu>, * University of Szeged, Hungary * + * Created by Arjan van de Ven <arjan@infradead.org> + * * For licensing information, see the file 'LICENCE' in this directory. * */ +#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt + #include "compr.h" static DEFINE_SPINLOCK(jffs2_compressor_list_lock); @@ -52,6 +55,78 @@ 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) { + pr_warn("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 @@ -75,47 +150,23 @@ 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, NULL); - 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: @@ -139,7 +190,8 @@ uint16_t jffs2_compress(struct jffs2_sb_info *c, struct jffs2_inode_info *f, tmp_buf = kmalloc(orig_slen, GFP_KERNEL); spin_lock(&jffs2_compressor_list_lock); if (!tmp_buf) { - printk(KERN_WARNING "JFFS2: No memory for compressor allocation. (%d bytes)\n", orig_slen); + pr_warn("No memory for compressor allocation. (%d bytes)\n", + orig_slen); continue; } else { @@ -151,7 +203,7 @@ uint16_t jffs2_compress(struct jffs2_sb_info *c, struct jffs2_inode_info *f, spin_unlock(&jffs2_compressor_list_lock); *datalen = orig_slen; *cdatalen = orig_dlen; - compr_ret = this->compress(data_in, this->compr_buf, datalen, cdatalen, NULL); + compr_ret = this->compress(data_in, this->compr_buf, datalen, cdatalen); spin_lock(&jffs2_compressor_list_lock); this->usecount--; if (!compr_ret) { @@ -173,22 +225,28 @@ 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"); + pr_err("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; } @@ -219,10 +277,11 @@ int jffs2_decompress(struct jffs2_sb_info *c, struct jffs2_inode_info *f, if (comprtype == this->compr) { this->usecount++; spin_unlock(&jffs2_compressor_list_lock); - ret = this->decompress(cdata_in, data_out, cdatalen, datalen, NULL); + ret = this->decompress(cdata_in, data_out, cdatalen, datalen); spin_lock(&jffs2_compressor_list_lock); if (ret) { - printk(KERN_WARNING "Decompressor \"%s\" returned %d\n", this->name, ret); + pr_warn("Decompressor \"%s\" returned %d\n", + this->name, ret); } else { this->stat_decompr_blocks++; @@ -232,7 +291,7 @@ int jffs2_decompress(struct jffs2_sb_info *c, struct jffs2_inode_info *f, return ret; } } - printk(KERN_WARNING "JFFS2 compression type 0x%02x not available.\n", comprtype); + pr_warn("compression type 0x%02x not available\n", comprtype); spin_unlock(&jffs2_compressor_list_lock); return -EIO; } @@ -244,7 +303,7 @@ int jffs2_register_compressor(struct jffs2_compressor *comp) struct jffs2_compressor *this; if (!comp->name) { - printk(KERN_WARNING "NULL compressor name at registering JFFS2 compressor. Failed.\n"); + pr_warn("NULL compressor name at registering JFFS2 compressor. Failed.\n"); return -1; } comp->compr_buf_size=0; @@ -254,7 +313,7 @@ int jffs2_register_compressor(struct jffs2_compressor *comp) comp->stat_compr_new_size=0; comp->stat_compr_blocks=0; comp->stat_decompr_blocks=0; - D1(printk(KERN_DEBUG "Registering JFFS2 compressor \"%s\"\n", comp->name)); + jffs2_dbg(1, "Registering JFFS2 compressor \"%s\"\n", comp->name); spin_lock(&jffs2_compressor_list_lock); @@ -277,15 +336,15 @@ out: int jffs2_unregister_compressor(struct jffs2_compressor *comp) { - D2(struct jffs2_compressor *this;) + D2(struct jffs2_compressor *this); - D1(printk(KERN_DEBUG "Unregistering JFFS2 compressor \"%s\"\n", comp->name)); + jffs2_dbg(1, "Unregistering JFFS2 compressor \"%s\"\n", comp->name); spin_lock(&jffs2_compressor_list_lock); if (comp->usecount) { spin_unlock(&jffs2_compressor_list_lock); - printk(KERN_WARNING "JFFS2: Compressor modul is in use. Unregister failed.\n"); + pr_warn("Compressor module is in use. Unregister failed.\n"); return -1; } list_del(&comp->list); @@ -322,17 +381,17 @@ int __init jffs2_compressors_init(void) /* Setting default compression mode */ #ifdef CONFIG_JFFS2_CMODE_NONE jffs2_compression_mode = JFFS2_COMPR_MODE_NONE; - D1(printk(KERN_INFO "JFFS2: default compression mode: none\n");) + jffs2_dbg(1, "default compression mode: none\n"); #else #ifdef CONFIG_JFFS2_CMODE_SIZE jffs2_compression_mode = JFFS2_COMPR_MODE_SIZE; - D1(printk(KERN_INFO "JFFS2: default compression mode: size\n");) + jffs2_dbg(1, "default compression mode: size\n"); #else #ifdef CONFIG_JFFS2_CMODE_FAVOURLZO jffs2_compression_mode = JFFS2_COMPR_MODE_FAVOURLZO; - D1(printk(KERN_INFO "JFFS2: default compression mode: favourlzo\n");) + jffs2_dbg(1, "default compression mode: favourlzo\n"); #else - D1(printk(KERN_INFO "JFFS2: default compression mode: priority\n");) + jffs2_dbg(1, "default compression mode: priority\n"); #endif #endif #endif |
