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author | Jeremy Fitzhardinge <jeremy.fitzhardinge@citrix.com> | 2009-04-07 22:34:16 +0200 |
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committer | Jeremy Fitzhardinge <jeremy.fitzhardinge@citrix.com> | 2009-04-07 22:34:16 +0200 |
commit | 38f4b8c0da01ae7cd9b93386842ce272d6fde9ab (patch) | |
tree | 3c8c52201aac038094bfea7efdd0984a8f62045e /fs/proc/generic.c | |
parent | Merge branch 'for-linus/xen/core' into for-linus/xen/master (diff) | |
parent | Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/jba... (diff) | |
download | linux-38f4b8c0da01ae7cd9b93386842ce272d6fde9ab.tar.xz linux-38f4b8c0da01ae7cd9b93386842ce272d6fde9ab.zip |
Merge commit 'origin/master' into for-linus/xen/master
* commit 'origin/master': (4825 commits)
Fix build errors due to CONFIG_BRANCH_TRACER=y
parport: Use the PCI IRQ if offered
tty: jsm cleanups
Adjust path to gpio headers
KGDB_SERIAL_CONSOLE check for module
Change KCONFIG name
tty: Blackin CTS/RTS
Change hardware flow control from poll to interrupt driven
Add support for the MAX3100 SPI UART.
lanana: assign a device name and numbering for MAX3100
serqt: initial clean up pass for tty side
tty: Use the generic RS485 ioctl on CRIS
tty: Correct inline types for tty_driver_kref_get()
splice: fix deadlock in splicing to file
nilfs2: support nanosecond timestamp
nilfs2: introduce secondary super block
nilfs2: simplify handling of active state of segments
nilfs2: mark minor flag for checkpoint created by internal operation
nilfs2: clean up sketch file
nilfs2: super block operations fix endian bug
...
Conflicts:
arch/x86/include/asm/thread_info.h
arch/x86/lguest/boot.c
drivers/xen/manage.c
Diffstat (limited to 'fs/proc/generic.c')
-rw-r--r-- | fs/proc/generic.c | 63 |
1 files changed, 53 insertions, 10 deletions
diff --git a/fs/proc/generic.c b/fs/proc/generic.c index 5d2989e9dcc1..fa678abc9db1 100644 --- a/fs/proc/generic.c +++ b/fs/proc/generic.c @@ -37,7 +37,7 @@ static int proc_match(int len, const char *name, struct proc_dir_entry *de) #define PROC_BLOCK_SIZE (PAGE_SIZE - 1024) static ssize_t -proc_file_read(struct file *file, char __user *buf, size_t nbytes, +__proc_file_read(struct file *file, char __user *buf, size_t nbytes, loff_t *ppos) { struct inode * inode = file->f_path.dentry->d_inode; @@ -183,19 +183,47 @@ proc_file_read(struct file *file, char __user *buf, size_t nbytes, } static ssize_t +proc_file_read(struct file *file, char __user *buf, size_t nbytes, + loff_t *ppos) +{ + struct proc_dir_entry *pde = PDE(file->f_path.dentry->d_inode); + ssize_t rv = -EIO; + + spin_lock(&pde->pde_unload_lock); + if (!pde->proc_fops) { + spin_unlock(&pde->pde_unload_lock); + return rv; + } + pde->pde_users++; + spin_unlock(&pde->pde_unload_lock); + + rv = __proc_file_read(file, buf, nbytes, ppos); + + pde_users_dec(pde); + return rv; +} + +static ssize_t proc_file_write(struct file *file, const char __user *buffer, size_t count, loff_t *ppos) { - struct inode *inode = file->f_path.dentry->d_inode; - struct proc_dir_entry * dp; - - dp = PDE(inode); - - if (!dp->write_proc) - return -EIO; + struct proc_dir_entry *pde = PDE(file->f_path.dentry->d_inode); + ssize_t rv = -EIO; + + if (pde->write_proc) { + spin_lock(&pde->pde_unload_lock); + if (!pde->proc_fops) { + spin_unlock(&pde->pde_unload_lock); + return rv; + } + pde->pde_users++; + spin_unlock(&pde->pde_unload_lock); - /* FIXME: does this routine need ppos? probably... */ - return dp->write_proc(file, buffer, count, dp->data); + /* FIXME: does this routine need ppos? probably... */ + rv = pde->write_proc(file, buffer, count, pde->data); + pde_users_dec(pde); + } + return rv; } @@ -307,6 +335,21 @@ static DEFINE_SPINLOCK(proc_inum_lock); /* protects the above */ /* * Return an inode number between PROC_DYNAMIC_FIRST and * 0xffffffff, or zero on failure. + * + * Current inode allocations in the proc-fs (hex-numbers): + * + * 00000000 reserved + * 00000001-00000fff static entries (goners) + * 001 root-ino + * + * 00001000-00001fff unused + * 0001xxxx-7fffxxxx pid-dir entries for pid 1-7fff + * 80000000-efffffff unused + * f0000000-ffffffff dynamic entries + * + * Goal: + * Once we split the thing into several virtual filesystems, + * we will get rid of magical ranges (and this comment, BTW). */ static unsigned int get_inode_number(void) { |