xiaomi-sm8450/android_kernel_xiaomi_sm8450
1
0
Fork 0
Code Issues Pull Requests Actions Packages Projects Releases Wiki Activity

ext4 crypto: shrink size of the ext4_crypto_ctx structure

Browse Source 
Some fields are only used when the crypto_ctx is being used on the
read path, some are only used on the write path, and some are only
used when the structure is on free list.  Optimize memory use by using
a union.

Signed-off-by: Theodore Ts'o <tytso@mit.edu>
This commit is contained in:
Theodore Ts'o
2015-05-31 13:31:34 -04:00
parent 1aaa6e8b24
commit 614def7013
4 changed files with 30 additions and 34 deletions
Download Patch File Download Diff File Expand all files Collapse all files

31
fs/ext4/crypto.c
View File

@@ -71,14 +71,14 @@ void ext4_release_crypto_ctx(struct ext4_crypto_ctx *ctx)
{
unsigned long flags;
if (ctx->bounce_page) {
if (ctx->flags & EXT4_WRITE_PATH_FL && ctx->w.bounce_page) {
if (ctx->flags & EXT4_BOUNCE_PAGE_REQUIRES_FREE_ENCRYPT_FL)
__free_page(ctx->bounce_page);
__free_page(ctx->w.bounce_page);
else
mempool_free(ctx->bounce_page, ext4_bounce_page_pool);
ctx->bounce_page = NULL;
mempool_free(ctx->w.bounce_page, ext4_bounce_page_pool);
}
ctx->control_page = NULL;
ctx->w.bounce_page = NULL;
ctx->w.control_page = NULL;
if (ctx->flags & EXT4_CTX_REQUIRES_FREE_ENCRYPT_FL) {
if (ctx->tfm)
crypto_free_tfm(ctx->tfm);
@@ -134,6 +134,7 @@ struct ext4_crypto_ctx *ext4_get_crypto_ctx(struct inode *inode)
} else {
ctx->flags &= ~EXT4_CTX_REQUIRES_FREE_ENCRYPT_FL;
}
ctx->flags &= ~EXT4_WRITE_PATH_FL;
/* Allocate a new Crypto API context if we don't already have
* one or if it isn't the right mode. */
@@ -165,10 +166,6 @@ struct ext4_crypto_ctx *ext4_get_crypto_ctx(struct inode *inode)
}
BUG_ON(ci->ci_size != ext4_encryption_key_size(ci->ci_data_mode));
/* There shouldn't be a bounce page attached to the crypto
* context at this point. */
BUG_ON(ctx->bounce_page);
out:
if (res) {
if (!IS_ERR_OR_NULL(ctx))
@@ -189,15 +186,6 @@ void ext4_exit_crypto(void)
struct ext4_crypto_ctx *pos, *n;
list_for_each_entry_safe(pos, n, &ext4_free_crypto_ctxs, free_list) {
if (pos->bounce_page) {
if (pos->flags &
EXT4_BOUNCE_PAGE_REQUIRES_FREE_ENCRYPT_FL) {
__free_page(pos->bounce_page);
} else {
mempool_free(pos->bounce_page,
ext4_bounce_page_pool);
}
}
if (pos->tfm)
crypto_free_tfm(pos->tfm);
kmem_cache_free(ext4_crypto_ctx_cachep, pos);
@@ -425,8 +413,9 @@ struct page *ext4_encrypt(struct inode *inode,
} else {
ctx->flags |= EXT4_BOUNCE_PAGE_REQUIRES_FREE_ENCRYPT_FL;
}
ctx->bounce_page = ciphertext_page;
ctx->control_page = plaintext_page;
ctx->flags |= EXT4_WRITE_PATH_FL;
ctx->w.bounce_page = ciphertext_page;
ctx->w.control_page = plaintext_page;
err = ext4_page_crypto(ctx, inode, EXT4_ENCRYPT, plaintext_page->index,
plaintext_page, ciphertext_page);
if (err) {
@@ -505,7 +494,7 @@ int ext4_encrypted_zeroout(struct inode *inode, struct ext4_extent *ex)
} else {
ctx->flags |= EXT4_BOUNCE_PAGE_REQUIRES_FREE_ENCRYPT_FL;
}
ctx->bounce_page = ciphertext_page;
ctx->w.bounce_page = ciphertext_page;
while (len--) {
err = ext4_page_crypto(ctx, inode, EXT4_ENCRYPT, lblk,