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truncate_pagecache(9) [centos man page]

TRUNCATE_PAGECACHE(9)					    Memory Management in Linux					     TRUNCATE_PAGECACHE(9)

NAME
truncate_pagecache - unmap and remove pagecache that has been truncated SYNOPSIS
void truncate_pagecache(struct inode * inode, loff_t oldsize, loff_t newsize); ARGUMENTS
inode inode oldsize old file size newsize new file size DESCRIPTION
inode's new i_size must already be written before truncate_pagecache is called. This function should typically be called before the filesystem releases resources associated with the freed range (eg. deallocates blocks). This way, pagecache will always stay logically coherent with on-disk format, and the filesystem would not have to deal with situations such as writepage being called for a page that has already had its underlying blocks deallocated. COPYRIGHT
Kernel Hackers Manual 3.10 June 2014 TRUNCATE_PAGECACHE(9)

Check Out this Related Man Page

MREMAP(2)						      BSD System Calls Manual							 MREMAP(2)

NAME
mremap -- re-map a virtual memory address LIBRARY
Standard C Library (libc, -lc) SYNOPSIS
#include <sys/mman.h> void * mremap(void *oldp, size_t oldsize, void *newp, size_t newsize, int flags); DESCRIPTION
The mremap() function resizes the mapped range (see mmap(2)) starting at oldp and having size oldsize to newsize. The following arguments can be OR'ed together in the flags argument: MAP_ALIGNED(n) The allocation should be aligned to the given boundary, i.e. ensure that the lowest n bits of the address are zero. The parameter n should be the base 2 logarithm of the desired alignment (e.g., to request alignment to 16K, use 14 as the value for n). The alignment must be equal to or greater than the platform's page size as returned by sysconf(3) with the _SC_PAGESIZE request. MAP_FIXED newp is tried and mremap() fails if that address can't be used as new base address for the range. Otherwise, oldp and newp are used as hints for the position, factoring in the given alignment. RETURN VALUES
mremap() returns the new address or MAP_FAILED, if the remap failed. COMPATIBILITY
The semantics of mremap() differ from the one provided by glibc on Linux in that the newp argument was added and a different set of flags are implemented. SEE ALSO
mmap(2), munmap(2) HISTORY
The mremap() system call appeared in NetBSD 5.0. It was based on the code that supports mremap() compatibility for Linux binaries. BSD
February 14, 2008 BSD
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