FIND_LOCK_PAGE(9) Memory Management in Linux FIND_LOCK_PAGE(9)NAME
find_lock_page - locate, pin and lock a pagecache page
SYNOPSIS
struct page * find_lock_page(struct address_space * mapping, pgoff_t offset);
ARGUMENTS
mapping
the address_space to search
offset
the page index
DESCRIPTION
Locates the desired pagecache page, locks it, increments its reference count and returns its address.
Returns zero if the page was not present. find_lock_page may sleep.
COPYRIGHT Kernel Hackers Manual 2.6. July 2010 FIND_LOCK_PAGE(9)
Check Out this Related Man Page
JOURNAL_TRY_TO_FREE_(9) The Linux Journalling API JOURNAL_TRY_TO_FREE_(9)NAME
journal_try_to_free_buffers - try to free page buffers.
SYNOPSIS
int journal_try_to_free_buffers(journal_t * journal, struct page * page, gfp_t gfp_mask);
ARGUMENTS
journal
journal for operation
page
to try and free
gfp_mask
we use the mask to detect how hard should we try to release buffers. If __GFP_WAIT and __GFP_FS is set, we wait for commit code to
release the buffers.
DESCRIPTION
For all the buffers on this page, if they are fully written out ordered data, move them onto BUF_CLEAN so try_to_free_buffers can reap
them.
This function returns non-zero if we wish try_to_free_buffers to be called. We do this if the page is releasable by try_to_free_buffers. We
also do it if the page has locked or dirty buffers and the caller wants us to perform sync or async writeout.
This complicates JBD locking somewhat. We aren't protected by the BKL here. We wish to remove the buffer from its committing or running
transaction's ->t_datalist via __journal_unfile_buffer.
This may *change* the value of transaction_t->t_datalist, so anyone who looks at t_datalist needs to lock against this function.
Even worse, someone may be doing a journal_dirty_data on this buffer. So we need to lock against that. journal_dirty_data will come out of
the lock with the buffer dirty, which makes it ineligible for release here.
Who else is affected by this? hmm... Really the only contender is do_get_write_access - it could be looking at the buffer while
journal_try_to_free_buffer is changing its state. But that cannot happen because we never reallocate freed data as metadata while the data
is part of a transaction. Yes?
Return 0 on failure, 1 on success
AUTHORS
Roger Gammans <rgammans@computer-surgery.co.uk>
Author.
Stephen Tweedie <sct@redhat.com>
Author.
COPYRIGHT Kernel Hackers Manual 2.6. July 2010 JOURNAL_TRY_TO_FREE_(9)
Hi all,
I want to create a new user and grant him ONLY transfer files access to a specific directory where he can only upload and read the files. He should be restricted to this activity only.
Regards (6 Replies)
Hi everyone,
I know the following questions are noobish questions but I am asking them because I am confused about the basics of history behind UNIX and LINUX.
Ok onto business, my questions are-:
Was/Is UNIX ever an open source operating system ?
If UNIX was... (21 Replies)
Hi,
Last 2 weeks I have searched many forums and i haven't found the answer for the question:
How to get all command output to Putty title?
Needed it for other programs to know when some jobs on a server is done and is it done right or wrong. Plink stdout and stdin wasn't working, i used many... (1 Reply)
anyone have any idea how do to this with auth_attr?
I suspect if I grant him
solaris.device.:RO::Device Allocation::help=DevAllocHeader.html
that will work but I'm unsure. Just looking for a second opinion. (10 Replies)
I am looking for a stable, reliable system to replace my current Windows systems in the home. These are simple systems that I purchased from the local Big Box store.
I have heard many good things about Unix and it's various children and it sounds like a good option to me. I have worked... (2 Replies)
We have a lot of scripts using cut as :
cut -c 0-8 --works for cut (GNU coreutils) 5.97, but does not work for cut (GNU coreutils) 8.4.
Gives error -
cut: fields and positions are numbered from 1
Try `cut --help' for more information.
The position needs to start with 1 for later... (6 Replies)
I've got a problem with a proxy configuration. We have an LDAP group that lists all users who are authorised to use the proxy to FTP (usually Filezilla) out to the world, and by implication those not in the group should be denied. My users are delighted that this has been enabled and those that... (9 Replies)
hi folks,
how to using tar with exclude directory and compress it using tar.Z
i only know how to exclude dir only with this command below:
tar -cvf /varios/restore/test.tar -X excludefile.txt /jfma/test1/
how to compress it using 1 command?
Thanx
Please use CODE tags as... (6 Replies)
Hello All,
I had recently learnt a bit of Docker(which provides containerization process).
Here are some of my learning points from it.
Let us start first with very basic question:
What is Docker:
Docker is a platform for sysadmins and developers to DEPLOY, DEVELOP and RUN applications ... (7 Replies)
What is the point of this? Whenever I close my shell it appends to the history file without adding this. I have never seen it overwrite my history file.
# When the shell exits, append to the history file instead of overwriting it
shopt -s histappend (3 Replies)
Hello for all,
I am testing the behavior of a 32 bit application running on Solaris 5.10 (SPARC), and realize it reaches 4GB of memory and then crashes.
It doesn't matter the amount of used memory as application is intended to perform many transactions; rather, what I want to achieve is to... (2 Replies)