1.. _cn_magicnumbers:
2
3.. include:: ../disclaimer-zh_CN.rst
4
5:Original: :ref:`Documentation/process/magic-number.rst <magicnumbers>`
6
7如果想评论或更新本文的内容,请直接发信到LKML。如果你使用英文交流有困难的话,也可
8以向中文版维护者求助。如果本翻译更新不及时或者翻译存在问题,请联系中文版维护者::
9
10        中文版维护者: 贾威威 Jia Wei Wei <harryxiyou@gmail.com>
11        中文版翻译者: 贾威威 Jia Wei Wei <harryxiyou@gmail.com>
12        中文版校译者: 贾威威 Jia Wei Wei <harryxiyou@gmail.com>
13
14Linux 魔术数
15============
16
17这个文件是有关当前使用的魔术值注册表。当你给一个结构添加了一个魔术值,你也应该把这个魔术值添加到这个文件,因为我们最好把用于各种结构的魔术值统一起来。
18
19使用魔术值来保护内核数据结构是一个非常好的主意。这就允许你在运行期检查(a)一个结构是否已经被攻击,或者(b)你已经给一个例行程序通过了一个错误的结构。后一种情况特别地有用---特别是当你通过一个空指针指向结构体的时候。tty源码,例如,经常通过特定驱动使用这种方法并且反复地排列特定方面的结构。
20
21使用魔术值的方法是在结构的开始处声明的,如下::
22
23        struct tty_ldisc {
24	        int	magic;
25        	...
26        };
27
28当你以后给内核添加增强功能的时候,请遵守这条规则!这样就会节省数不清的调试时间,特别是一些古怪的情况,例如,数组超出范围并且重新写了超出部分。遵守这个规则,‪这些情况可以被快速地,安全地避免。
29
30		Theodore Ts'o
31		  31 Mar 94
32
33给当前的Linux 2.1.55添加魔术表。
34
35		Michael Chastain
36		<mailto:mec@shout.net>
37		22 Sep 1997
38
39现在应该最新的Linux 2.1.112.因为在特性冻结期间,不能在2.2.x前改变任何东西。这些条目被数域所排序。
40
41		Krzysztof G.Baranowski
42	        <mailto: kgb@knm.org.pl>
43		29 Jul 1998
44
45更新魔术表到Linux 2.5.45。刚好越过特性冻结,但是有可能还会有一些新的魔术值在2.6.x之前融入到内核中。
46
47		Petr Baudis
48		<pasky@ucw.cz>
49		03 Nov 2002
50
51更新魔术表到Linux 2.5.74。
52
53		Fabian Frederick
54                <ffrederick@users.sourceforge.net>
55		09 Jul 2003
56
57===================== ================ ======================== ==========================================
58魔术数名              数字             结构                     文件
59===================== ================ ======================== ==========================================
60PG_MAGIC              'P'              pg_{read,write}_hdr      ``include/linux/pg.h``
61CMAGIC                0x0111           user                     ``include/linux/a.out.h``
62MKISS_DRIVER_MAGIC    0x04bf           mkiss_channel            ``drivers/net/mkiss.h``
63HDLC_MAGIC            0x239e           n_hdlc                   ``drivers/char/n_hdlc.c``
64APM_BIOS_MAGIC        0x4101           apm_user                 ``arch/x86/kernel/apm_32.c``
65CYCLADES_MAGIC        0x4359           cyclades_port            ``include/linux/cyclades.h``
66DB_MAGIC              0x4442           fc_info                  ``drivers/net/iph5526_novram.c``
67DL_MAGIC              0x444d           fc_info                  ``drivers/net/iph5526_novram.c``
68FASYNC_MAGIC          0x4601           fasync_struct            ``include/linux/fs.h``
69FF_MAGIC              0x4646           fc_info                  ``drivers/net/iph5526_novram.c``
70ISICOM_MAGIC          0x4d54           isi_port                 ``include/linux/isicom.h``
71PTY_MAGIC             0x5001                                    ``drivers/char/pty.c``
72PPP_MAGIC             0x5002           ppp                      ``include/linux/if_pppvar.h``
73SERIAL_MAGIC          0x5301           async_struct             ``include/linux/serial.h``
74SSTATE_MAGIC          0x5302           serial_state             ``include/linux/serial.h``
75SLIP_MAGIC            0x5302           slip                     ``drivers/net/slip.h``
76STRIP_MAGIC           0x5303           strip                    ``drivers/net/strip.c``
77X25_ASY_MAGIC         0x5303           x25_asy                  ``drivers/net/x25_asy.h``
78SIXPACK_MAGIC         0x5304           sixpack                  ``drivers/net/hamradio/6pack.h``
79AX25_MAGIC            0x5316           ax_disp                  ``drivers/net/mkiss.h``
80TTY_MAGIC             0x5401           tty_struct               ``include/linux/tty.h``
81MGSL_MAGIC            0x5401           mgsl_info                ``drivers/char/synclink.c``
82TTY_DRIVER_MAGIC      0x5402           tty_driver               ``include/linux/tty_driver.h``
83MGSLPC_MAGIC          0x5402           mgslpc_info              ``drivers/char/pcmcia/synclink_cs.c``
84TTY_LDISC_MAGIC       0x5403           tty_ldisc                ``include/linux/tty_ldisc.h``
85USB_SERIAL_MAGIC      0x6702           usb_serial               ``drivers/usb/serial/usb-serial.h``
86FULL_DUPLEX_MAGIC     0x6969                                    ``drivers/net/ethernet/dec/tulip/de2104x.c``
87USB_BLUETOOTH_MAGIC   0x6d02           usb_bluetooth            ``drivers/usb/class/bluetty.c``
88RFCOMM_TTY_MAGIC      0x6d02                                    ``net/bluetooth/rfcomm/tty.c``
89USB_SERIAL_PORT_MAGIC 0x7301           usb_serial_port          ``drivers/usb/serial/usb-serial.h``
90CG_MAGIC              0x00090255       ufs_cylinder_group       ``include/linux/ufs_fs.h``
91RPORT_MAGIC           0x00525001       r_port                   ``drivers/char/rocket_int.h``
92LSEMAGIC              0x05091998       lse                      ``drivers/fc4/fc.c``
93GDTIOCTL_MAGIC        0x06030f07       gdth_iowr_str            ``drivers/scsi/gdth_ioctl.h``
94RIEBL_MAGIC           0x09051990                                ``drivers/net/atarilance.c``
95NBD_REQUEST_MAGIC     0x12560953       nbd_request              ``include/linux/nbd.h``
96RED_MAGIC2            0x170fc2a5       (any)                    ``mm/slab.c``
97BAYCOM_MAGIC          0x19730510       baycom_state             ``drivers/net/baycom_epp.c``
98ISDN_X25IFACE_MAGIC   0x1e75a2b9       isdn_x25iface_proto_data ``drivers/isdn/isdn_x25iface.h``
99ECP_MAGIC             0x21504345       cdkecpsig                ``include/linux/cdk.h``
100LSOMAGIC              0x27091997       lso                      ``drivers/fc4/fc.c``
101LSMAGIC               0x2a3b4d2a       ls                       ``drivers/fc4/fc.c``
102WANPIPE_MAGIC         0x414C4453       sdla_{dump,exec}         ``include/linux/wanpipe.h``
103CS_CARD_MAGIC         0x43525553       cs_card                  ``sound/oss/cs46xx.c``
104LABELCL_MAGIC         0x4857434c       labelcl_info_s           ``include/asm/ia64/sn/labelcl.h``
105ISDN_ASYNC_MAGIC      0x49344C01       modem_info               ``include/linux/isdn.h``
106CTC_ASYNC_MAGIC       0x49344C01       ctc_tty_info             ``drivers/s390/net/ctctty.c``
107ISDN_NET_MAGIC        0x49344C02       isdn_net_local_s         ``drivers/isdn/i4l/isdn_net_lib.h``
108SAVEKMSG_MAGIC2       0x4B4D5347       savekmsg                 ``arch/*/amiga/config.c``
109CS_STATE_MAGIC        0x4c4f4749       cs_state                 ``sound/oss/cs46xx.c``
110SLAB_C_MAGIC          0x4f17a36d       kmem_cache               ``mm/slab.c``
111COW_MAGIC             0x4f4f4f4d       cow_header_v1            ``arch/um/drivers/ubd_user.c``
112I810_CARD_MAGIC       0x5072696E       i810_card                ``sound/oss/i810_audio.c``
113TRIDENT_CARD_MAGIC    0x5072696E       trident_card             ``sound/oss/trident.c``
114ROUTER_MAGIC          0x524d4157       wan_device               [in ``wanrouter.h`` pre 3.9]
115SAVEKMSG_MAGIC1       0x53415645       savekmsg                 ``arch/*/amiga/config.c``
116GDA_MAGIC             0x58464552       gda                      ``arch/mips/include/asm/sn/gda.h``
117RED_MAGIC1            0x5a2cf071       (any)                    ``mm/slab.c``
118EEPROM_MAGIC_VALUE    0x5ab478d2       lanai_dev                ``drivers/atm/lanai.c``
119HDLCDRV_MAGIC         0x5ac6e778       hdlcdrv_state            ``include/linux/hdlcdrv.h``
120PCXX_MAGIC            0x5c6df104       channel                  ``drivers/char/pcxx.h``
121KV_MAGIC              0x5f4b565f       kernel_vars_s            ``arch/mips/include/asm/sn/klkernvars.h``
122I810_STATE_MAGIC      0x63657373       i810_state               ``sound/oss/i810_audio.c``
123TRIDENT_STATE_MAGIC   0x63657373       trient_state             ``sound/oss/trident.c``
124M3_CARD_MAGIC         0x646e6f50       m3_card                  ``sound/oss/maestro3.c``
125FW_HEADER_MAGIC       0x65726F66       fw_header                ``drivers/atm/fore200e.h``
126SLOT_MAGIC            0x67267321       slot                     ``drivers/hotplug/cpqphp.h``
127SLOT_MAGIC            0x67267322       slot                     ``drivers/hotplug/acpiphp.h``
128LO_MAGIC              0x68797548       nbd_device               ``include/linux/nbd.h``
129OPROFILE_MAGIC        0x6f70726f       super_block              ``drivers/oprofile/oprofilefs.h``
130M3_STATE_MAGIC        0x734d724d       m3_state                 ``sound/oss/maestro3.c``
131VMALLOC_MAGIC         0x87654320       snd_alloc_track          ``sound/core/memory.c``
132KMALLOC_MAGIC         0x87654321       snd_alloc_track          ``sound/core/memory.c``
133PWC_MAGIC             0x89DC10AB       pwc_device               ``drivers/usb/media/pwc.h``
134NBD_REPLY_MAGIC       0x96744668       nbd_reply                ``include/linux/nbd.h``
135ENI155_MAGIC          0xa54b872d       midway_eprom	        ``drivers/atm/eni.h``
136CODA_MAGIC            0xC0DAC0DA       coda_file_info           ``fs/coda/coda_fs_i.h``
137DPMEM_MAGIC           0xc0ffee11       gdt_pci_sram             ``drivers/scsi/gdth.h``
138YAM_MAGIC             0xF10A7654       yam_port                 ``drivers/net/hamradio/yam.c``
139CCB_MAGIC             0xf2691ad2       ccb                      ``drivers/scsi/ncr53c8xx.c``
140QUEUE_MAGIC_FREE      0xf7e1c9a3       queue_entry              ``drivers/scsi/arm/queue.c``
141QUEUE_MAGIC_USED      0xf7e1cc33       queue_entry              ``drivers/scsi/arm/queue.c``
142HTB_CMAGIC            0xFEFAFEF1       htb_class                ``net/sched/sch_htb.c``
143NMI_MAGIC             0x48414d4d455201 nmi_s                    ``arch/mips/include/asm/sn/nmi.h``
144===================== ================ ======================== ==========================================
145
146
147请注意,在声音记忆管理中仍然有一些特殊的为每个驱动定义的魔术值。查看include/sound/sndmagic.h来获取他们完整的列表信息。很多OSS声音驱动拥有自己从声卡PCI ID构建的魔术值-他们也没有被列在这里。
148
149IrDA子系统也使用了大量的自己的魔术值,查看include/net/irda/irda.h来获取他们完整的信息。
150
151HFS是另外一个比较大的使用魔术值的文件系统-你可以在fs/hfs/hfs.h中找到他们。
152