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| author | Theodore Ts'o <tytso@mit.edu> | 2015-05-31 20:31:34 +0300 |
|---|---|---|
| committer | Theodore Ts'o <tytso@mit.edu> | 2015-05-31 20:31:34 +0300 |
| commit | 614def7013574ffcd54019b6df40ac1c0df754af (patch) | |
| tree | 50549389b403fac7179bc6f93ecb178091ad4c31 /fs/ext4/crypto.c | |
| parent | 1aaa6e8b24114757a836ae0e62d2096deb76f274 (diff) | |
| download | linux-614def7013574ffcd54019b6df40ac1c0df754af.tar.xz | |
ext4 crypto: shrink size of the ext4_crypto_ctx structure
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>
Diffstat (limited to 'fs/ext4/crypto.c')
| -rw-r--r-- | fs/ext4/crypto.c | 31 |
1 files changed, 10 insertions, 21 deletions
diff --git a/fs/ext4/crypto.c b/fs/ext4/crypto.c index 9969d054cd88..28a0e4bd91b0 100644 --- a/fs/ext4/crypto.c +++ b/fs/ext4/crypto.c @@ -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, |