Memory Management
[Linux DDE Common]

This module emulates the Memory Management subsystem inside the Linux kernel. More...

Modules
group	Address Conversion
	Linux' __va()/%__pa() macro replacements.
group	Page Allocation/Deallocation
	Page allocation just triggers mapping and deallocation triggers unmapping.
group	Slab Caches
	This simple slab cache emulation was introduced for the Linux USB drivers.
Functions
void *	kmalloc (size_t size, int gfp)
	kmem Allocation
void	kfree (const void *addr)
	kmem Deallocation
void *	vmalloc (unsigned long size)
	vmem Allocation
void	vfree (void *addr)
	vmem Deallocation
int	l4dde_mm_init (unsigned int max_vsize, unsigned int max_ksize)
	Initalize LMM pools and initial regions.

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Detailed Description

This module emulates the Memory Management subsystem inside the Linux kernel.

Linux DDE manages two OSKit LMM pools for memory allocations - one for kmalloc() (kmem) and one for vmalloc() (vmem) allocations. Each pool consists of one ore more LMM regions.

Malloc functions have to keep track of chunk sizes and store them in the first dword of the chunk.

Requirements: (additionally to Global Requirements)

• OSKit lmm library

Configuration:

• setup MM_KREGIONS to change number of kernel memory regions (default 1!)
• maximum size of pools is configured via parameters of l4dde_mm_init()

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Function Documentation

void kfree (  const void *  addr  )

kmem Deallocation Parameters: addr  start address of memory chunk to free This is Linux' kfree(). Definition at line 223 of file mm.c. References DEBUG_MALLOC_EACH, klock, and kpool. Referenced by pci_pool_destroy().

void* kmalloc (  size_t  size, int  gfp )

kmem Allocation Parameters: size  size of memory chunk gfp  flags This is Linux' kmalloc(). Returns: start address of allocated chunk; NULL on error Definition at line 183 of file mm.c. References __more_kcore(), DEBUG_MALLOC_EACH, DEBUG_MSG, klock, and kpool. Referenced by pci_pool_create().

int l4dde_mm_init (  unsigned int  max_vsize, unsigned int  max_ksize )

Initalize LMM pools and initial regions. Parameters: max_vsize  max size of virtual memory allocations max_ksize  max size of kernel memory allocations Returns: 0 on success, negative error code otherwise Sizes are rounded up to multiples of page size. kmem pool is divided into MM_KREGIONS regions of same size. The total size will be max_ksize (or greater because of rounding/page size). vmem pool has only one region of max_vsize. Definition at line 398 of file mm.c. References __setup_kmem(), __setup_vmem(), _initialized, DEBUG_ERRORS, and MM_KREGIONS.

void vfree (  void *  addr  )

vmem Deallocation Parameters: addr  start address of memory chunk to release This is Linux' vfree(). Definition at line 286 of file mm.c. References DEBUG_MALLOC_EACH, vlock, and vpool. Referenced by __sound_remove_unit(), __start_kernel_thread(), kmem_cache_destroy(), and sound_insert_unit().

void* vmalloc (  unsigned long  size  )

vmem Allocation Parameters: size  size of memory chunk Returns: start address of allocated chunk; NULL on error This is Linux' vmalloc(). Definition at line 249 of file mm.c. References __more_vcore(), DEBUG_MALLOC_EACH, vlock, and vpool. Referenced by dde_add_region(), kernel_thread(), kmem_cache_create(), l4dde_process_add_worker(), l4dde_process_init(), and sound_insert_unit().

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