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Diffstat (limited to 'fs/jffs2/compr.c')
-rw-r--r--fs/jffs2/compr.c167
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