For files only using THIS_MODULE and/or EXPORT_SYMBOL, map them onto including export.h -- or if the file isn't even using those, then just delete the include. Fix up any implicit include dependencies that were being masked by module.h along the way. Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com>
On most architectures division is an expensive operation and accessing an element currently requires four of them. This performance penalty effectively precludes flex arrays from being used on any kind of fast path. However, two of these divisions can be handled at creation time and the others can be replaced by a reciprocal divide, completely avoiding real divisions on access. [eparis@redhat.com: rebase on top of changes to support 0 len elements] [eparis@redhat.com: initialize part_nr when array fits entirely in base] Signed-off-by: Jesse Gross <jesse@nicira.com> Signed-off-by: Eric Paris <eparis@redhat.com> Cc: Dave Hansen <dave@linux.vnet.ibm.com> Cc: David Rientjes <rientjes@google.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
flex_arrays are supposed to be a replacement for: kmalloc(num_elements * sizeof(element)) If kmalloc is given 0 num_elements or a 0 size element it will happily return ZERO_SIZE_PTR. Which looks like a valid allocation, but which will explode if something actually try to use it. The current flex_array code will return an equivalent result if num_elements is 0, but will fail to work if sizeof(element) is 0. This patch allows allocation to work even for 0 size elements. It will cause flex_arrays to explode though if they are used. Imitating the kmalloc behavior. Based-on-patch-by: Steffen Klassert <steffen.klassert@secunet.com> Signed-off-by: Eric Paris <eparis@redhat.com> Acked-by: Dave Hansen <dave@linux.vnet.ibm.com>
Just like kmalloc will allow one to allocate a 0 length segment of memory flex arrays should do the same thing. It should bomb if you try to use something, but it should at least allow the allocation. This is needed because when SELinux switched to using flex_arrays in 2.6.38 the inability to allocate a 0 length array resulted in SELinux policy load returning -ENOSPC when previously it worked. Based-on-patch-by: Steffen Klassert <steffen.klassert@secunet.com> Signed-off-by: Eric Paris <eparis@redhat.com> Tested-by: Chris Richards <gizmo@giz-works.com> Cc: stable@kernel.org [2.6.38+]
Change flex_array_prealloc to take the number of elements for which space should be allocated instead of the last (inclusive) element. Users and documentation are updated accordingly. flex_arrays got introduced before they had users. When folks started using it, they ended up needing a different API than was coded up originally. This swaps over to the API that folks apparently need. Based-on-patch-by: Steffen Klassert <steffen.klassert@secunet.com> Signed-off-by: Eric Paris <eparis@redhat.com> Tested-by: Chris Richards <gizmo@giz-works.com> Acked-by: Dave Hansen <dave@linux.vnet.ibm.com> Cc: stable@kernel.org [2.6.38+]
Alex said: I want to use flex_array to store a sparse array of ATM cell re-assembly buffers for my ATM over Ethernet driver. Using the per-vcc user_back structure causes problems when stacked with things like br2684. Add EXPORT_SYMBOL() for all publically accessible flex array functions and move to obj-y so that modules may use this library. Signed-off-by: David Rientjes <rientjes@google.com> Cc: Dave Hansen <dave@linux.vnet.ibm.com> Cc: Paul Mundt <lethal@linux-sh.org> Reported-by: Alex Bennee <kernel-hacker@bennee.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>