diff options
Diffstat (limited to 'Documentation/filesystems')
| -rw-r--r-- | Documentation/filesystems/00-INDEX | 2 | ||||
| -rw-r--r-- | Documentation/filesystems/9p.txt | 4 | ||||
| -rw-r--r-- | Documentation/filesystems/Locking | 33 | ||||
| -rw-r--r-- | Documentation/filesystems/ext4.txt | 14 | ||||
| -rw-r--r-- | Documentation/filesystems/nfs/00-INDEX | 4 | ||||
| -rw-r--r-- | Documentation/filesystems/nfs/idmapper.txt | 67 | ||||
| -rw-r--r-- | Documentation/filesystems/nfs/nfsroot.txt | 22 | ||||
| -rw-r--r-- | Documentation/filesystems/nfs/pnfs.txt | 48 | ||||
| -rw-r--r-- | Documentation/filesystems/ocfs2.txt | 7 | ||||
| -rw-r--r-- | Documentation/filesystems/proc.txt | 25 | ||||
| -rw-r--r-- | Documentation/filesystems/sharedsubtree.txt | 4 | ||||
| -rw-r--r-- | Documentation/filesystems/smbfs.txt | 8 | ||||
| -rw-r--r-- | Documentation/filesystems/xfs-delayed-logging-design.txt | 11 |
13 files changed, 208 insertions, 41 deletions
diff --git a/Documentation/filesystems/00-INDEX b/Documentation/filesystems/00-INDEX index 4303614b5ad..8c624a18f67 100644 --- a/Documentation/filesystems/00-INDEX +++ b/Documentation/filesystems/00-INDEX @@ -96,8 +96,6 @@ seq_file.txt - how to use the seq_file API sharedsubtree.txt - a description of shared subtrees for namespaces. -smbfs.txt - - info on using filesystems with the SMB protocol (Win 3.11 and NT). spufs.txt - info and mount options for the SPU filesystem used on Cell. sysfs-pci.txt diff --git a/Documentation/filesystems/9p.txt b/Documentation/filesystems/9p.txt index f9765e8cf08..b22abba78fe 100644 --- a/Documentation/filesystems/9p.txt +++ b/Documentation/filesystems/9p.txt @@ -111,7 +111,7 @@ OPTIONS This can be used to share devices/named pipes/sockets between hosts. This functionality will be expanded in later versions. - access there are three access modes. + access there are four access modes. user = if a user tries to access a file on v9fs filesystem for the first time, v9fs sends an attach command (Tattach) for that user. @@ -120,6 +120,8 @@ OPTIONS the files on the mounted filesystem any = v9fs does single attach and performs all operations as one user + client = ACL based access check on the 9p client + side for access validation cachetag cache tag to use the specified persistent cache. cache tags for existing cache sessions can be listed at diff --git a/Documentation/filesystems/Locking b/Documentation/filesystems/Locking index 2db4283efa8..a91f3089001 100644 --- a/Documentation/filesystems/Locking +++ b/Documentation/filesystems/Locking @@ -322,7 +322,6 @@ fl_release_private: yes yes prototypes: int (*fl_compare_owner)(struct file_lock *, struct file_lock *); void (*fl_notify)(struct file_lock *); /* unblock callback */ - void (*fl_copy_lock)(struct file_lock *, struct file_lock *); void (*fl_release_private)(struct file_lock *); void (*fl_break)(struct file_lock *); /* break_lease callback */ @@ -330,7 +329,6 @@ locking rules: BKL may block fl_compare_owner: yes no fl_notify: yes no -fl_copy_lock: yes no fl_release_private: yes yes fl_break: yes no @@ -349,21 +347,36 @@ call this method upon the IO completion. --------------------------- block_device_operations ----------------------- prototypes: - int (*open) (struct inode *, struct file *); - int (*release) (struct inode *, struct file *); - int (*ioctl) (struct inode *, struct file *, unsigned, unsigned long); + int (*open) (struct block_device *, fmode_t); + int (*release) (struct gendisk *, fmode_t); + int (*ioctl) (struct block_device *, fmode_t, unsigned, unsigned long); + int (*compat_ioctl) (struct block_device *, fmode_t, unsigned, unsigned long); + int (*direct_access) (struct block_device *, sector_t, void **, unsigned long *); int (*media_changed) (struct gendisk *); + void (*unlock_native_capacity) (struct gendisk *); int (*revalidate_disk) (struct gendisk *); + int (*getgeo)(struct block_device *, struct hd_geometry *); + void (*swap_slot_free_notify) (struct block_device *, unsigned long); locking rules: - BKL bd_sem -open: yes yes -release: yes yes -ioctl: yes no + BKL bd_mutex +open: no yes +release: no yes +ioctl: no no +compat_ioctl: no no +direct_access: no no media_changed: no no +unlock_native_capacity: no no revalidate_disk: no no +getgeo: no no +swap_slot_free_notify: no no (see below) + +media_changed, unlock_native_capacity and revalidate_disk are called only from +check_disk_change(). + +swap_slot_free_notify is called with swap_lock and sometimes the page lock +held. -The last two are called only from check_disk_change(). --------------------------- file_operations ------------------------------- prototypes: diff --git a/Documentation/filesystems/ext4.txt b/Documentation/filesystems/ext4.txt index e1def1786e5..6ab9442d7ee 100644 --- a/Documentation/filesystems/ext4.txt +++ b/Documentation/filesystems/ext4.txt @@ -353,6 +353,20 @@ noauto_da_alloc replacing existing files via patterns such as system crashes before the delayed allocation blocks are forced to disk. +noinit_itable Do not initialize any uninitialized inode table + blocks in the background. This feature may be + used by installation CD's so that the install + process can complete as quickly as possible; the + inode table initialization process would then be + deferred until the next time the file system + is unmounted. + +init_itable=n The lazy itable init code will wait n times the + number of milliseconds it took to zero out the + previous block group's inode table. This + minimizes the impact on the systme performance + while file system's inode table is being initialized. + discard Controls whether ext4 should issue discard/TRIM nodiscard(*) commands to the underlying block device when blocks are freed. This is useful for SSD devices diff --git a/Documentation/filesystems/nfs/00-INDEX b/Documentation/filesystems/nfs/00-INDEX index 2f68cd68876..a57e12411d2 100644 --- a/Documentation/filesystems/nfs/00-INDEX +++ b/Documentation/filesystems/nfs/00-INDEX @@ -12,5 +12,9 @@ nfs-rdma.txt - how to install and setup the Linux NFS/RDMA client and server software nfsroot.txt - short guide on setting up a diskless box with NFS root filesystem. +pnfs.txt + - short explanation of some of the internals of the pnfs client code rpc-cache.txt - introduction to the caching mechanisms in the sunrpc layer. +idmapper.txt + - information for configuring request-keys to be used by idmapper diff --git a/Documentation/filesystems/nfs/idmapper.txt b/Documentation/filesystems/nfs/idmapper.txt new file mode 100644 index 00000000000..b9b4192ea8b --- /dev/null +++ b/Documentation/filesystems/nfs/idmapper.txt @@ -0,0 +1,67 @@ + +========= +ID Mapper +========= +Id mapper is used by NFS to translate user and group ids into names, and to +translate user and group names into ids. Part of this translation involves +performing an upcall to userspace to request the information. Id mapper will +user request-key to perform this upcall and cache the result. The program +/usr/sbin/nfs.idmap should be called by request-key, and will perform the +translation and initialize a key with the resulting information. + + NFS_USE_NEW_IDMAPPER must be selected when configuring the kernel to use this + feature. + +=========== +Configuring +=========== +The file /etc/request-key.conf will need to be modified so /sbin/request-key can +direct the upcall. The following line should be added: + +#OP TYPE DESCRIPTION CALLOUT INFO PROGRAM ARG1 ARG2 ARG3 ... +#====== ======= =============== =============== =============================== +create id_resolver * * /usr/sbin/nfs.idmap %k %d 600 + +This will direct all id_resolver requests to the program /usr/sbin/nfs.idmap. +The last parameter, 600, defines how many seconds into the future the key will +expire. This parameter is optional for /usr/sbin/nfs.idmap. When the timeout +is not specified, nfs.idmap will default to 600 seconds. + +id mapper uses for key descriptions: + uid: Find the UID for the given user + gid: Find the GID for the given group + user: Find the user name for the given UID + group: Find the group name for the given GID + +You can handle any of these individually, rather than using the generic upcall +program. If you would like to use your own program for a uid lookup then you +would edit your request-key.conf so it look similar to this: + +#OP TYPE DESCRIPTION CALLOUT INFO PROGRAM ARG1 ARG2 ARG3 ... +#====== ======= =============== =============== =============================== +create id_resolver uid:* * /some/other/program %k %d 600 +create id_resolver * * /usr/sbin/nfs.idmap %k %d 600 + +Notice that the new line was added above the line for the generic program. +request-key will find the first matching line and corresponding program. In +this case, /some/other/program will handle all uid lookups and +/usr/sbin/nfs.idmap will handle gid, user, and group lookups. + +See <file:Documentation/keys-request-keys.txt> for more information about the +request-key function. + + +========= +nfs.idmap +========= +nfs.idmap is designed to be called by request-key, and should not be run "by +hand". This program takes two arguments, a serialized key and a key +description. The serialized key is first converted into a key_serial_t, and +then passed as an argument to keyctl_instantiate (both are part of keyutils.h). + +The actual lookups are performed by functions found in nfsidmap.h. nfs.idmap +determines the correct function to call by looking at the first part of the +description string. For example, a uid lookup description will appear as +"uid:user@domain". + +nfs.idmap will return 0 if the key was instantiated, and non-zero otherwise. diff --git a/Documentation/filesystems/nfs/nfsroot.txt b/Documentation/filesystems/nfs/nfsroot.txt index f2430a7974e..90c71c6f0d0 100644 --- a/Documentation/filesystems/nfs/nfsroot.txt +++ b/Documentation/filesystems/nfs/nfsroot.txt @@ -159,6 +159,28 @@ ip=<client-ip>:<server-ip>:<gw-ip>:<netmask>:<hostname>:<device>:<autoconf> Default: any +nfsrootdebug + + This parameter enables debugging messages to appear in the kernel + log at boot time so that administrators can verify that the correct + NFS mount options, server address, and root path are passed to the + NFS client. + + +rdinit=<executable file> + + To specify which file contains the program that starts system + initialization, administrators can use this command line parameter. + The default value of this parameter is "/init". If the specified + file exists and the kernel can execute it, root filesystem related + kernel command line parameters, including `nfsroot=', are ignored. + + A description of the process of mounting the root file system can be + found in: + + Documentation/early-userspace/README + + 3.) Boot Loader diff --git a/Documentation/filesystems/nfs/pnfs.txt b/Documentation/filesystems/nfs/pnfs.txt new file mode 100644 index 00000000000..bc0b9cfe095 --- /dev/null +++ b/Documentation/filesystems/nfs/pnfs.txt @@ -0,0 +1,48 @@ +Reference counting in pnfs: +========================== + +The are several inter-related caches. We have layouts which can +reference multiple devices, each of which can reference multiple data servers. +Each data server can be referenced by multiple devices. Each device +can be referenced by multiple layouts. To keep all of this straight, +we need to reference count. + + +struct pnfs_layout_hdr +---------------------- +The on-the-wire command LAYOUTGET corresponds to struct +pnfs_layout_segment, usually referred to by the variable name lseg. +Each nfs_inode may hold a pointer to a cache of of these layout +segments in nfsi->layout, of type struct pnfs_layout_hdr. + +We reference the header for the inode pointing to it, across each +outstanding RPC call that references it (LAYOUTGET, LAYOUTRETURN, +LAYOUTCOMMIT), and for each lseg held within. + +Each header is also (when non-empty) put on a list associated with +struct nfs_client (cl_layouts). Being put on this list does not bump +the reference count, as the layout is kept around by the lseg that +keeps it in the list. + +deviceid_cache +-------------- +lsegs reference device ids, which are resolved per nfs_client and +layout driver type. The device ids are held in a RCU cache (struct +nfs4_deviceid_cache). The cache itself is referenced across each +mount. The entries (struct nfs4_deviceid) themselves are held across +the lifetime of each lseg referencing them. + +RCU is used because the deviceid is basically a write once, read many +data structure. The hlist size of 32 buckets needs better +justification, but seems reasonable given that we can have multiple +deviceid's per filesystem, and multiple filesystems per nfs_client. + +The hash code is copied from the nfsd code base. A discussion of +hashing and variations of this algorithm can be found at: +http://groups.google.com/group/comp.lang.c/browse_thread/thread/9522965e2b8d3809 + +data server cache +----------------- +file driver devices refer to data servers, which are kept in a module +level cache. Its reference is held over the lifetime of the deviceid +pointing to it. diff --git a/Documentation/filesystems/ocfs2.txt b/Documentation/filesystems/ocfs2.txt index 1f7ae144f6d..5393e661169 100644 --- a/Documentation/filesystems/ocfs2.txt +++ b/Documentation/filesystems/ocfs2.txt @@ -87,3 +87,10 @@ dir_resv_level= (*) By default, directory reservations will scale with file reservations - users should rarely need to change this value. If allocation reservations are turned off, this option will have no effect. +coherency=full (*) Disallow concurrent O_DIRECT writes, cluster inode + lock will be taken to force other nodes drop cache, + therefore full cluster coherency is guaranteed even + for O_DIRECT writes. +coherency=buffered Allow concurrent O_DIRECT writes without EX lock among + nodes, which gains high performance at risk of getting + stale data on other nodes. diff --git a/Documentation/filesystems/proc.txt b/Documentation/filesystems/proc.txt index a6aca874088..e73df2722ff 100644 --- a/Documentation/filesystems/proc.txt +++ b/Documentation/filesystems/proc.txt @@ -136,6 +136,7 @@ Table 1-1: Process specific entries in /proc statm Process memory status information status Process status in human readable form wchan If CONFIG_KALLSYMS is set, a pre-decoded wchan + pagemap Page table stack Report full stack trace, enable via CONFIG_STACKTRACE smaps a extension based on maps, showing the memory consumption of each mapping @@ -370,17 +371,24 @@ Shared_Dirty: 0 kB Private_Clean: 0 kB Private_Dirty: 0 kB Referenced: 892 kB +Anonymous: 0 kB Swap: 0 kB KernelPageSize: 4 kB MMUPageSize: 4 kB -The first of these lines shows the same information as is displayed for the -mapping in /proc/PID/maps. The remaining lines show the size of the mapping, -the amount of the mapping that is currently resident in RAM, the "proportional -set size” (divide each shared page by the number of processes sharing it), the -number of clean and dirty shared pages in the mapping, and the number of clean -and dirty private pages in the mapping. The "Referenced" indicates the amount -of memory currently marked as referenced or accessed. +The first of these lines shows the same information as is displayed for the +mapping in /proc/PID/maps. The remaining lines show the size of the mapping +(size), the amount of the mapping that is currently resident in RAM (RSS), the +process' proportional share of this mapping (PSS), the number of clean and +dirty private pages in the mapping. Note that even a page which is part of a +MAP_SHARED mapping, but has only a single pte mapped, i.e. is currently used +by only one process, is accounted as private and not as shared. "Referenced" +indicates the amount of memory currently marked as referenced or accessed. +"Anonymous" shows the amount of memory that does not belong to any file. Even +a mapping associated with a file may contain anonymous pages: when MAP_PRIVATE +and a page is modified, the file page is replaced by a private anonymous copy. +"Swap" shows how much would-be-anonymous memory is also used, but out on +swap. This file is only present if the CONFIG_MMU kernel configuration option is enabled. @@ -397,6 +405,9 @@ To clear the bits for the file mapped pages associated with the process > echo 3 > /proc/PID/clear_refs Any other value written to /proc/PID/clear_refs will have no effect. +The /proc/pid/pagemap gives the PFN, which can be used to find the pageflags +using /proc/kpageflags and number of times a page is mapped using +/proc/kpagecount. For detailed explanation, see Documentation/vm/pagemap.txt. 1.2 Kernel data --------------- diff --git a/Documentation/filesystems/sharedsubtree.txt b/Documentation/filesystems/sharedsubtree.txt index fc0e39af43c..4ede421c968 100644 --- a/Documentation/filesystems/sharedsubtree.txt +++ b/Documentation/filesystems/sharedsubtree.txt @@ -62,10 +62,10 @@ replicas continue to be exactly same. # mount /dev/sd0 /tmp/a #ls /tmp/a - t1 t2 t2 + t1 t2 t3 #ls /mnt/a - t1 t2 t2 + t1 t2 t3 Note that the mount has propagated to the mount at /mnt as well. diff --git a/Documentation/filesystems/smbfs.txt b/Documentation/filesystems/smbfs.txt deleted file mode 100644 index 194fb0decd2..00000000000 --- a/Documentation/filesystems/smbfs.txt +++ /dev/null @@ -1,8 +0,0 @@ -Smbfs is a filesystem that implements the SMB protocol, which is the -protocol used by Windows for Workgroups, Windows 95 and Windows NT. -Smbfs was inspired by Samba, the program written by Andrew Tridgell -that turns any Unix host into a file server for DOS or Windows clients. - -Smbfs is a SMB client, but uses parts of samba for its operation. For -more info on samba, including documentation, please go to -http://www.samba.org/ and then on to your nearest mirror. diff --git a/Documentation/filesystems/xfs-delayed-logging-design.txt b/Documentation/filesystems/xfs-delayed-logging-design.txt index 96d0df28bed..7445bf335da 100644 --- a/Documentation/filesystems/xfs-delayed-logging-design.txt +++ b/Documentation/filesystems/xfs-delayed-logging-design.txt @@ -794,17 +794,6 @@ designed. Roadmap: -2.6.37 Remove experimental tag from mount option - => should be roughly 6 months after initial merge - => enough time to: - => gain confidence and fix problems reported by early - adopters (a.k.a. guinea pigs) - => address worst performance regressions and undesired - behaviours - => start tuning/optimising code for parallelism - => start tuning/optimising algorithms consuming - excessive CPU time - 2.6.39 Switch default mount option to use delayed logging => should be roughly 12 months after initial merge => enough time to shake out remaining problems before next round of |