xnu-6153.41.3.tar.gz

[apple/xnu.git] / bsd / sys / decmpfs.h

diff --git a/bsd/sys/decmpfs.h b/bsd/sys/decmpfs.h
index f8a61d2888b599d62e5627c46a3916a29565aeef..51fbdfdd62e615be0d83cb5ec57178bc2d622886 100644 (file)
--- a/bsd/sys/decmpfs.h
+++ b/bsd/sys/decmpfs.h
@@ -2,7 +2,7 @@
  * Copyright (c) 2008 Apple Inc. All rights reserved.
  *
  * @APPLE_OSREFERENCE_LICENSE_HEADER_START@
  * Copyright (c) 2008 Apple Inc. All rights reserved.
  *
  * @APPLE_OSREFERENCE_LICENSE_HEADER_START@

- * 
+ *

  * This file contains Original Code and/or Modifications of Original Code
  * as defined in and that are subject to the Apple Public Source License
  * Version 2.0 (the 'License'). You may not use this file except in
  * This file contains Original Code and/or Modifications of Original Code
  * as defined in and that are subject to the Apple Public Source License
  * Version 2.0 (the 'License'). You may not use this file except in


@@ -11,10 +11,10 @@
  * unlawful or unlicensed copies of an Apple operating system, or to
  * circumvent, violate, or enable the circumvention or violation of, any
  * terms of an Apple operating system software license agreement.
  * unlawful or unlicensed copies of an Apple operating system, or to
  * circumvent, violate, or enable the circumvention or violation of, any
  * terms of an Apple operating system software license agreement.

- * 
+ *

  * Please obtain a copy of the License at
  * http://www.opensource.apple.com/apsl/ and read it before using this file.
  * Please obtain a copy of the License at
  * http://www.opensource.apple.com/apsl/ and read it before using this file.

- * 
+ *

  * The Original Code and all software distributed under the License are
  * distributed on an 'AS IS' basis, WITHOUT WARRANTY OF ANY KIND, EITHER
  * EXPRESS OR IMPLIED, AND APPLE HEREBY DISCLAIMS ALL SUCH WARRANTIES,
  * The Original Code and all software distributed under the License are
  * distributed on an 'AS IS' basis, WITHOUT WARRANTY OF ANY KIND, EITHER
  * EXPRESS OR IMPLIED, AND APPLE HEREBY DISCLAIMS ALL SUCH WARRANTIES,


@@ -22,82 +22,184 @@
  * FITNESS FOR A PARTICULAR PURPOSE, QUIET ENJOYMENT OR NON-INFRINGEMENT.
  * Please see the License for the specific language governing rights and
  * limitations under the License.
  * FITNESS FOR A PARTICULAR PURPOSE, QUIET ENJOYMENT OR NON-INFRINGEMENT.
  * Please see the License for the specific language governing rights and
  * limitations under the License.

- * 
+ *

  * @APPLE_OSREFERENCE_LICENSE_HEADER_END@
  */
 #ifndef _SYS_DECMPFS_H_
 #define _SYS_DECMPFS_H_ 1
 
  * @APPLE_OSREFERENCE_LICENSE_HEADER_END@
  */
 #ifndef _SYS_DECMPFS_H_
 #define _SYS_DECMPFS_H_ 1
 

+#include <stdbool.h>
+#include <sys/kdebug.h>
+#include <sys/kernel_types.h>
+#include <sys/vnode.h>
+
+/*
+ * Please switch on @DECMPFS_ENABLE_KDEBUG_TRACES to enable tracepoints.
+ * Tracepoints are compiled out by default to eliminate any overhead due to
+ * kernel tracing.
+ *
+ * #define DECMPFS_ENABLE_KDEBUG_TRACES 1
+ */
+#if DECMPFS_ENABLE_KDEBUG_TRACES
+#define DECMPFS_EMIT_TRACE_ENTRY(D, ...) \
+       KDBG_FILTERED((D) | DBG_FUNC_START, ## __VA_ARGS__)
+#define DECMPFS_EMIT_TRACE_RETURN(D, ...) \
+       KDBG_FILTERED((D) | DBG_FUNC_END, ##__VA_ARGS__)
+#else
+#define DECMPFS_EMIT_TRACE_ENTRY(D, ...) do {} while (0)
+#define DECMPFS_EMIT_TRACE_RETURN(D, ...) do {} while (0)
+#endif /* DECMPFS_ENABLE_KDEBUG_TRACES */
+
+/*
+ * KERNEL_DEBUG related definitions for decmpfs.
+ *
+ * Please NOTE: The Class DBG_FSYSTEM = 3, and Subclass DBG_DECMP = 0x12, so
+ * these debug codes are of the form 0x0312nnnn.
+ */
+#define DECMPDBG_CODE(code)  FSDBG_CODE(DBG_DECMP, code)
+
+enum {
+       DECMPDBG_DECOMPRESS_FILE            = DECMPDBG_CODE(0),/* 0x03120000 */
+       DECMPDBG_FETCH_COMPRESSED_HEADER    = DECMPDBG_CODE(1),/* 0x03120004 */
+       DECMPDBG_FETCH_UNCOMPRESSED_DATA    = DECMPDBG_CODE(2),/* 0x03120008 */
+       DECMPDBG_FREE_COMPRESSED_DATA       = DECMPDBG_CODE(4),/* 0x03120010 */
+       DECMPDBG_FILE_IS_COMPRESSED         = DECMPDBG_CODE(5),/* 0x03120014 */
+};
+

 #define MAX_DECMPFS_XATTR_SIZE 3802
 
 /*
 #define MAX_DECMPFS_XATTR_SIZE 3802
 
 /*

- NOTE:  decmpfs can only be used by thread-safe filesystems
+ *  NOTE:  decmpfs can only be used by thread-safe filesystems

  */
 
 #define DECMPFS_MAGIC 0x636d7066 /* cmpf */
 
 #define DECMPFS_XATTR_NAME "com.apple.decmpfs" /* extended attribute to use for decmpfs */
 
  */
 
 #define DECMPFS_MAGIC 0x636d7066 /* cmpf */
 
 #define DECMPFS_XATTR_NAME "com.apple.decmpfs" /* extended attribute to use for decmpfs */
 

+/*
+ * This single field is to be interpreted differently depending on the
+ * corresponding item type.
+ * For regular files: it is a 64bits-encoded logical size
+ * For directories: it is a 64bits-encoded number of children (ie st_nlink - 2)
+ * For packages: it is 40bits encoded size and 24bits number of children at root
+ */
+typedef struct __attribute__((packed)) {
+       uint64_t  value;
+} decmpfs_raw_item_size;
+
+#define DECMPFS_PKG_SIZE_MASK           0x000000ffffffffffULL
+#define DECMPFS_PKG_COUNT_MASK          0xffffff
+#define DECMPFS_PKG_CHLD_COUNT_SHIFT    40
+
+#define DECMPFS_PKG_SIZE(x)             ((x).value & DECMPFS_PKG_SIZE_MASK)
+#define DECMPFS_PKG_CHLD_COUNT(x)       ((uint32_t)(((x).value >> DECMPFS_PKG_CHLD_COUNT_SHIFT) & DECMPFS_PKG_COUNT_MASK))
+#define DECMPFS_PKG_VALUE_FROM_SIZE_COUNT(size, count) \
+       (((size) & DECMPFS_PKG_SIZE_MASK) | ((uint64_t)(count) << DECMPFS_PKG_CHLD_COUNT_SHIFT))
+
+/* Dataless file or directory */
+#define DATALESS_CMPFS_TYPE     0x80000001
+
+/* Dataless package, with number of root children and total size encoded on disk */
+#define DATALESS_PKG_CMPFS_TYPE 0x80000002
+
+
+static inline bool
+decmpfs_type_is_dataless(uint32_t cmp_type)
+{
+       return cmp_type == DATALESS_CMPFS_TYPE || cmp_type == DATALESS_PKG_CMPFS_TYPE;
+}
+

 typedef struct __attribute__((packed)) {
 typedef struct __attribute__((packed)) {

-    /* this structure represents the xattr on disk; the fields below are little-endian */
-    uint32_t compression_magic;
-    uint32_t compression_type;     /* see the enum below */
-    uint64_t uncompressed_size;
-    unsigned char attr_bytes[0];   /* the bytes of the attribute after the header */
+       /* this structure represents the xattr on disk; the fields below are little-endian */
+       uint32_t compression_magic;
+       uint32_t compression_type;   /* see the enum below */
+       union {
+               uint64_t uncompressed_size;  /* compatility accessor */
+               decmpfs_raw_item_size _size;
+       };
+       unsigned char attr_bytes[0]; /* the bytes of the attribute after the header */

 } decmpfs_disk_header;
 
 typedef struct __attribute__((packed)) {
 } decmpfs_disk_header;
 
 typedef struct __attribute__((packed)) {

-    /* this structure represents the xattr in memory; the fields below are host-endian */
-    uint32_t attr_size;
-    uint32_t compression_magic;
-    uint32_t compression_type;
-    uint64_t uncompressed_size;
-    unsigned char attr_bytes[0];   /* the bytes of the attribute after the header */
+       /* this structure represents the xattr in memory; the fields below are host-endian */
+       uint32_t attr_size;
+       uint32_t compression_magic;
+       uint32_t compression_type;
+       union {
+               /*
+                * although uncompressed_size remains available for backward-compatibility reasons
+                * the uncompressed size and nchildren should be accessed using the inline helpers
+                * below
+                */
+               uint64_t uncompressed_size;
+               decmpfs_raw_item_size _size;
+       };
+       unsigned char attr_bytes[0]; /* the bytes of the attribute after the header */

 } decmpfs_header;
 
 } decmpfs_header;
 

+static inline uint64_t
+decmpfs_get_uncompressed_size(const decmpfs_header *hdr)
+{
+       if (hdr->compression_magic == DECMPFS_MAGIC && hdr->compression_type == DATALESS_PKG_CMPFS_TYPE) {
+               return DECMPFS_PKG_SIZE(hdr->_size);
+       }
+
+       return hdr->uncompressed_size;
+}
+
+static inline uint32_t
+decmpfs_get_directory_entries(const decmpfs_header *hdr)
+{
+       if (hdr->compression_magic == DECMPFS_MAGIC && hdr->compression_type == DATALESS_PKG_CMPFS_TYPE) {
+               return DECMPFS_PKG_CHLD_COUNT(hdr->_size);
+       }
+
+       return (uint32_t)hdr->uncompressed_size;
+}
+

 /* compression_type values */
 enum {
 /* compression_type values */
 enum {

-    CMP_Type1       = 1, /* uncompressed data in xattr */
-    
-    /* additional types defined in AppleFSCompression project */
-    
-    CMP_MAX         = 255
+       CMP_Type1       = 1,/* uncompressed data in xattr */
+
+       /* additional types defined in AppleFSCompression project */
+
+       CMP_MAX         = 255/* Highest compression_type supported */

 };
 
 typedef struct {
 };
 
 typedef struct {

-    void *buf;
-    user_ssize_t size;
+       void *buf;
+       user_ssize_t size;

 } decmpfs_vector;
 
 } decmpfs_vector;
 

-#if KERNEL
+#ifdef KERNEL

 
 

-#include <kern/locks.h>
+#ifdef XNU_KERNEL_PRIVATE

 
 

-#if defined(__i386__) || defined(__x86_64__)
-#define DECMPFS_SUPPORTS_SWAP64 1
-/* otherwise, no OSCompareAndSwap64, so use a mutex */
-#endif
+#include <kern/locks.h>

 
 

-typedef struct decmpfs_cnode {
+struct decmpfs_cnode {

        uint8_t cmp_state;
        uint8_t cmp_state;

-       uint8_t cmp_minimal_xattr;       /* if non-zero, this file's com.apple.decmpfs xattr contained only the minimal decmpfs_disk_header */
+       uint8_t cmp_minimal_xattr;   /* if non-zero, this file's com.apple.decmpfs xattr contained only the minimal decmpfs_disk_header */

        uint32_t cmp_type;
        uint32_t lockcount;
        uint32_t cmp_type;
        uint32_t lockcount;

-       void    *lockowner;              /* cnode's lock owner (if a thread is currently holding an exclusive lock) */
-    uint64_t uncompressed_size __attribute__((aligned(8)));
-    lck_rw_t compressed_data_lock;
-#if !DECMPFS_SUPPORTS_SWAP64
-    /* we need a lock since we can't atomically fetch/set 64 bits */
-    lck_mtx_t uncompressed_size_mtx;
-#endif /* !DECMPFS_SUPPORTS_SWAP64 */
-} decmpfs_cnode;
+       void    *lockowner;          /* cnode's lock owner (if a thread is currently holding an exclusive lock) */
+       uint64_t uncompressed_size __attribute__((aligned(8)));
+       uint64_t nchildren __attribute__((aligned(8))); /* for dataless directories (incl. packages) */
+       uint64_t total_size __attribute__((aligned(8)));/* for dataless directories (incl. packages) */
+       uint64_t decompression_flags;
+       lck_rw_t compressed_data_lock;
+};
+
+#endif // XNU_KERNEL_PRIVATE
+
+typedef struct decmpfs_cnode decmpfs_cnode;

 
 /* return values from decmpfs_file_is_compressed */
 enum {
 
 /* return values from decmpfs_file_is_compressed */
 enum {

-    FILE_TYPE_UNKNOWN      = 0,
-    FILE_IS_NOT_COMPRESSED = 1,
-    FILE_IS_COMPRESSED     = 2,
-    FILE_IS_CONVERTING     = 3  /* file is converting from compressed to decompressed */
+       FILE_TYPE_UNKNOWN      = 0,
+       FILE_IS_NOT_COMPRESSED = 1,
+       FILE_IS_COMPRESSED     = 2,
+       FILE_IS_CONVERTING     = 3/* file is converting from compressed to decompressed */

 };
 
 /* vfs entrypoints */
 };
 
 /* vfs entrypoints */


@@ -105,19 +207,27 @@ extern vfs_context_t decmpfs_ctx;
 
 /* client filesystem entrypoints */
 void decmpfs_init(void);
 
 /* client filesystem entrypoints */
 void decmpfs_init(void);

+decmpfs_cnode *decmpfs_cnode_alloc(void);
+void decmpfs_cnode_free(decmpfs_cnode *dp);

 void decmpfs_cnode_init(decmpfs_cnode *cp);
 void decmpfs_cnode_destroy(decmpfs_cnode *cp);
 
 int decmpfs_hides_rsrc(vfs_context_t ctx, decmpfs_cnode *cp);
 int decmpfs_hides_xattr(vfs_context_t ctx, decmpfs_cnode *cp, const char *xattr);
 
 void decmpfs_cnode_init(decmpfs_cnode *cp);
 void decmpfs_cnode_destroy(decmpfs_cnode *cp);
 
 int decmpfs_hides_rsrc(vfs_context_t ctx, decmpfs_cnode *cp);
 int decmpfs_hides_xattr(vfs_context_t ctx, decmpfs_cnode *cp, const char *xattr);
 

-boolean_t decmpfs_trylock_compressed_data(decmpfs_cnode *cp, int exclusive);
+bool decmpfs_trylock_compressed_data(decmpfs_cnode *cp, int exclusive);

 void decmpfs_lock_compressed_data(decmpfs_cnode *cp, int exclusive);
 void decmpfs_unlock_compressed_data(decmpfs_cnode *cp, int exclusive);
 
 uint32_t decmpfs_cnode_get_vnode_state(decmpfs_cnode *cp);
 void decmpfs_cnode_set_vnode_state(decmpfs_cnode *cp, uint32_t state, int skiplock);
 uint64_t decmpfs_cnode_get_vnode_cached_size(decmpfs_cnode *cp);
 void decmpfs_lock_compressed_data(decmpfs_cnode *cp, int exclusive);
 void decmpfs_unlock_compressed_data(decmpfs_cnode *cp, int exclusive);
 
 uint32_t decmpfs_cnode_get_vnode_state(decmpfs_cnode *cp);
 void decmpfs_cnode_set_vnode_state(decmpfs_cnode *cp, uint32_t state, int skiplock);
 uint64_t decmpfs_cnode_get_vnode_cached_size(decmpfs_cnode *cp);

+uint64_t decmpfs_cnode_get_vnode_cached_nchildren(decmpfs_cnode *cp);
+uint64_t decmpfs_cnode_get_vnode_cached_total_size(decmpfs_cnode *cp);
+void decmpfs_cnode_set_vnode_cached_size(decmpfs_cnode *cp, uint64_t size);
+void decmpfs_cnode_set_vnode_cached_nchildren(decmpfs_cnode *cp, uint64_t nchildren);
+void decmpfs_cnode_set_vnode_cached_total_size(decmpfs_cnode *cp, uint64_t total_sz);
+uint32_t decmpfs_cnode_cmp_type(decmpfs_cnode *cp);

 
 int decmpfs_file_is_compressed(vnode_t vp, decmpfs_cnode *cp);
 errno_t decmpfs_validate_compressed_file(vnode_t vp, decmpfs_cnode *cp);
 
 int decmpfs_file_is_compressed(vnode_t vp, decmpfs_cnode *cp);
 errno_t decmpfs_validate_compressed_file(vnode_t vp, decmpfs_cnode *cp);


@@ -133,18 +243,29 @@ typedef int (*decmpfs_validate_compressed_file_func)(vnode_t vp, vfs_context_t c
 typedef void (*decmpfs_adjust_fetch_region_func)(vnode_t vp, vfs_context_t ctx, decmpfs_header *hdr, off_t *offset, user_ssize_t *size);
 typedef int (*decmpfs_fetch_uncompressed_data_func)(vnode_t vp, vfs_context_t ctx, decmpfs_header *hdr, off_t offset, user_ssize_t size, int nvec, decmpfs_vector *vec, uint64_t *bytes_read);
 typedef int (*decmpfs_free_compressed_data_func)(vnode_t vp, vfs_context_t ctx, decmpfs_header *hdr);
 typedef void (*decmpfs_adjust_fetch_region_func)(vnode_t vp, vfs_context_t ctx, decmpfs_header *hdr, off_t *offset, user_ssize_t *size);
 typedef int (*decmpfs_fetch_uncompressed_data_func)(vnode_t vp, vfs_context_t ctx, decmpfs_header *hdr, off_t offset, user_ssize_t size, int nvec, decmpfs_vector *vec, uint64_t *bytes_read);
 typedef int (*decmpfs_free_compressed_data_func)(vnode_t vp, vfs_context_t ctx, decmpfs_header *hdr);

+typedef uint64_t (*decmpfs_get_decompression_flags_func)(vnode_t vp, vfs_context_t ctx, decmpfs_header *hdr); // returns flags from the DECMPFS_FLAGS enumeration below
+
+enum {
+       DECMPFS_FLAGS_FORCE_FLUSH_ON_DECOMPRESS = 1 << 0,
+};
+
+/* Versions that are supported for binary compatibility */
+#define DECMPFS_REGISTRATION_VERSION_V1 1
+#define DECMPFS_REGISTRATION_VERSION_V3 3
+
+#define DECMPFS_REGISTRATION_VERSION (DECMPFS_REGISTRATION_VERSION_V3)

 
 

-#define DECMPFS_REGISTRATION_VERSION 1

 typedef struct {
 typedef struct {

-    int                                   decmpfs_registration;
-    decmpfs_validate_compressed_file_func validate;
-    decmpfs_adjust_fetch_region_func      adjust_fetch;
-    decmpfs_fetch_uncompressed_data_func  fetch;
-    decmpfs_free_compressed_data_func     free_data;
+       int                                   decmpfs_registration;
+       decmpfs_validate_compressed_file_func validate;
+       decmpfs_adjust_fetch_region_func      adjust_fetch;
+       decmpfs_fetch_uncompressed_data_func  fetch;
+       decmpfs_free_compressed_data_func     free_data;
+       decmpfs_get_decompression_flags_func  get_flags;

 } decmpfs_registration;
 
 /* hooks for kexts to call */
 } decmpfs_registration;
 
 /* hooks for kexts to call */

-errno_t register_decmpfs_decompressor(uint32_t compression_type, decmpfs_registration *registration);
+errno_t register_decmpfs_decompressor(uint32_t compression_type, const decmpfs_registration *registration);

 errno_t unregister_decmpfs_decompressor(uint32_t compression_type, decmpfs_registration *registration);
 
 #endif /* KERNEL */
 errno_t unregister_decmpfs_decompressor(uint32_t compression_type, decmpfs_registration *registration);
 
 #endif /* KERNEL */